Open Access

Variation in population levels of sedentary time in European children and adolescents according to cross-European studies: a systematic literature review within DEDIPAC

  • Maïté Verloigne1,
  • Anne Loyen2Email author,
  • Linde Van Hecke3, 4,
  • Jeroen Lakerveld2,
  • Ingrid Hendriksen5, 6,
  • Ilse De Bourdheaudhuij1,
  • Benedicte Deforche3,
  • Alan Donnelly7,
  • Ulf Ekelund8,
  • Johannes Brug2 and
  • Hidde P. van der Ploeg9, 10
International Journal of Behavioral Nutrition and Physical Activity201613:69

https://doi.org/10.1186/s12966-016-0395-5

Received: 2 December 2015

Accepted: 11 June 2016

Published: 28 June 2016

Abstract

Background

A high amount of sedentary time has been proposed as a risk factor for various health outcomes in adults. While the evidence is less clear in children and adolescents, monitoring sedentary time is important to understand the prevalence rates and how this behaviour varies over time and by place. This systematic literature review aims to provide an overview of existing cross-European studies on sedentary time in children (0-12y) and adolescents (13-18y), to describe the variation in population levels of sedentary time, and to discuss the impact of assessment methods.

Methods

Six literature databases were searched (PubMed, EMBASE, CINAHL, PsycINFO, SportDiscus and OpenGrey), followed by backward- and forward tracking and searching authors’ and experts’ literature databases. Included articles were observational studies reporting on levels of sedentary time in the general population of children and/or adolescents in at least two European countries. Population levels were reported separately for children and adolescents. Data were reviewed, extracted and assessed by two researchers, with disagreements being resolved by a third researcher. The review protocol is published under registration number CRD42014013379 in the PROSPERO database.

Results

Forty-two eligible articles were identified, most were cross-sectional (n = 38). The number of included European countries per article ranged from 2 to 36. Levels of sedentary time were observed to be higher in East-European countries compared to the rest of Europe. There was a large variation in assessment methods and reported outcome variables. The majority of articles used a child-specific questionnaire (60 %). Other methods included accelerometers, parental questionnaires or interviews and ecological momentary assessment tools. Television time was reported as outcome variable in 57 % of included articles (ranging from a mean value of 1 h to 2.7 h in children and 1.3 h to 4.4 h in adolescents), total sedentary time in 24 % (ranging from a mean value of 192 min to 552 min in children and from 268 min to 506 min in adolescents).

Conclusion

A substantial number of published studies report on levels of sedentary time in children and adolescents across European countries, but there was a large variation in assessment methods. Questionnaires (child specific) were used most often, but they mostly measured specific screen-based activities and did not assess total sedentary time. There is a need for harmonisation and standardisation of objective and subjective methods to assess sedentary time in children and adolescents to enable comparison across countries.

Keywords

Youth Prevalence Assessment method Health behaviour Europe

Background

Sedentary behaviour is defined as “any waking behaviour characterised by an energy expenditure of ≤ 1.5 metabolic equivalents while in a sitting or reclining position” [1]. The time spent in those sedentary behaviours has been defined as sedentary time. Although there is debate on the association between sedentary time and health outcomes in adults [2, 3], there are several studies, systematic reviews and meta-analyses showing that sedentary time has been positively associated with type 2 diabetes, cardiovascular diseases, metabolic syndrome and all-cause mortality among adults, independently from moderate to vigorous physical activity or subcomponents of physical activity [49]. Among children and adolescents, the evidence is less conclusive [1012]. A possible reason is that some of the health outcomes may not be easily manifested in childhood or adolescence [10]. However, a recent review of reviews has suggested that there is an association between children’s screen-time behaviours (i.e. domain-specific sedentary behaviours) and obesity, blood pressure, total cholesterol, self-esteem, social behaviour problems, physical fitness and academic achievement [4]. Moreover, since sedentary time in early life may track into adulthood where it may have potential health implications and since children and adolescents spend a lot of time sedentary [13], actions may be considered to reduce time spent sedentary in children and adolescents. An important step to guide targeted action is to monitor the levels of sedentary time among children and adolescents across countries. This step is needed to study how the mean population levels of sedentary time vary by place, how it changes over time, and to evaluate preventive strategies and policies. In addition, it would be relevant to study and monitor the population levels of sedentary time specifically in Europe as it has its own governing structures but also a wide range of different cultures. Although the countries within Europe are diverse regarding political, economic, (socio-)cultural and physical environmental contexts, they are currently all struggling with an alarming increase in lifestyle related diseases such as overweight and obesity. This means that more effective efforts to reduce sedentary time in Europe are needed and monitoring the behaviour is a first step to address this need [14]. Focusing on specific European evidence is important to formulate public health guidelines and policy recommendations at the appropriate European level.

The DEDIPAC (DEterminants of DIet and Physical ACtivity) Knowledge Hub was established in 2013 by twelve European Union Member States [14]. One of the aims of DEDIPAC is “to enable a better standardised and more continuous cross-European monitoring of behaviours (including sedentary time) and changes in these behaviours across the life course and within populations to identify both targets and target populations for (policy) interventions”. A first and crucial step within DEDIPAC towards standardisation and harmonisation is to provide an overview of existing cross-European surveillance studies in order to describe population levels of (un)healthy behaviour by conjointly performing four systematic literature reviews. The reason to focus on cross-European studies is based on a 2010 WHO report concluding that even though population levels of health behaviour are frequently monitored across Europe, national surveys are not comparable due to differences in assessment methods [15]. Thus, focusing on cross-European initiatives at least enables within-study country comparison.

Therefore, this systematic literature review aims (a) to provide an overview of the existing cross-European studies (including data of at least two European countries) on sedentary time in children, (b) to describe the variation in population levels of sedentary time in European children and adolescents (0-18 years) according to these studies, and (c) to discuss the impact of assessment methods used. The other three reviews focus on the population levels of (1) sedentary time in adults [16], (2) physical activity in adults [17], and (3) physical activity in youth [18].

Methods

As described in the introduction, this systematic literature review is part of a set of four reviews. Because the four systematic reviews originate from the same project, have similar objectives (although for different behaviours and/or age groups) and share their methodology, the introduction, methods and discussion sections of the review articles have obvious similarities. The search, article selection, data extraction and quality assessment were conducted conjointly for all four reviews. Subsequently, the included articles were allocated to the appropriate review article(s). If an article included both youth (<18 years) and adults (≥18 years) and presented stratified results, those stratified results were used in the appropriate review. If the article did not present stratified results, the article was allocated to the most appropriate review, based on the mean age (and age distribution) of the study sample. One article could be included in multiple reviews. Before the search commenced, review protocols were written based on the “Centre for Reviews and Dissemination’s guidance for undertaking reviews in health care” [19], and registered in the PROSPERO database (http://www.crd.york.ac.uk/PROSPERO/). The review protocol on sedentary time in youth is published under registration number CRD42014013379. The reporting of this systematic review adheres to the preferred reporting items of the PRISMA-P checklist (see Additional file 1).

Search strategy

The search was conducted in June 2014 and updated on the 29th of February, 2016. Six databases (PubMed, EMBASE, CINAHL, PsycINFO, SportDiscus and OpenGrey) were searched using similar search strategies, adapted to each database. The following search terms were used: ‘Physical activity’ OR ‘Sedentary behaviour’ AND ‘Europe’ (including all individual country names) AND ‘Countries‘/’Multicountry’/’International’. Both the index terms and the title and abstract were searched and synonyms (e.g. for sedentary behaviour: sitting, screen time, etc.) were used. The complete search string can be found in Additional file 2. Based on the in- and exclusion criteria described below, search filters of the databases were used when possible, for example to select the appropriate publication period or language. In addition, complementary search strategies were used. After the full-text review phase, the reference lists of the included articles were scanned (backward tracking) and a citation search was performed for the included articles (forward tracking) to identify potentially appropriate articles. Also, several experts in the field of physical activity and sedentary time were contacted to provide additional articles. Finally, all authors involved in the four reviews were asked to search their own literature databases for appropriate articles. All additionally retrieved articles underwent the same selection process as the original articles - as described below.

Article selection

All retrieved records were imported into Reference Manager 12 (Thomson Reuters, New York). Duplicates were hand-searched and removed. Records were included if they were journal articles, reports or doctoral dissertations (further referred to as ‘articles’) written in English. To be included, articles needed to report on observational studies conducted after 01-01-2000 in the general, healthy population. This was done to avoid the reporting of outdated data. In addition, articles were only included if they provided data for two or more European countries (as defined by the Council of Europe) [20]. Articles were included if they reported total sedentary time (e.g. minutes/day), time spent sitting at school, time spent on screen-time behaviours (e.g. television viewing, using a computer) and/or time spent at any other sedentary activity. Both subjective (e.g. questionnaires) and objective (e.g. accelerometers) measures were included.

Three researchers (AL, LVH, MV) were involved in the article selection, data extraction and quality assessment. For the title selection, the three researchers each independently reviewed 1/3 of the titles of the retrieved articles. For the abstract and the full-text selection, data extraction and quality assessment, the three researchers each covered 2/3 of the articles, so that each article was independently reviewed, extracted and assessed by two different researchers. Disagreement between the two researchers was resolved by the third researcher.

Data extraction

A standardised data extraction file was used to extract data regarding the study characteristics, study sample, assessment methods, reported outcomes, and findings. We did not obtain the original data. The complete data extraction file can be found in Additional file 3. To present the data more clearly and to allow for comparisons between age groups, the results are presented and discussed separately for children (aged 0-12 years) and adolescents (aged 13-18 years).

Quality assessment

A quality score was used to provide a general overview of the quality of the included articles. The ‘Standard quality assessment criteria for evaluating primary research papers from a variety of fields’ was used for the assessment [21]. The checklist consists of fourteen items to be scored ‘Yes’ (2 points), ‘Partial’ (1 point), ‘No’ (0 points) and ‘Not applicable’. The summary score was calculated as follows: Total sum ((number of ‘Yes’ x 2) + (number of ‘Partial’ x 1))/Total possible sum (28 – (number of ‘Not applicable’ x 2)). This instrument was chosen because it provides the opportunity to assess and compare the quality of different study designs, focuses on both the research and the reporting, and allows researchers to indicate that an item is not applicable, without affecting the total quality score. The complete quality assessment file can be found in Additional file 4.

Results

Overview of the existing cross-European studies on sedentary time in children

The search resulted in 9756 articles, after duplicates were removed. Based on titles and abstracts, the full text of 581 potentially relevant articles was retrieved and reviewed. This resulted in a total of 80 articles, of which 42 reported on levels of sedentary time in children and/or adolescents (Fig. 1) [2263]. Table 1 provides an overview of the characteristics of the included articles. In brief, most articles were cross-sectional (n = 38), the quality score ranged from 0.64 to 1.0 on a scale from 0 to 1, the number of included European countries ranged from 2 to 36, and sample size ranged from 503 to 443,821. The majority of articles (n = 37) were part of a larger European study, that is the COSI study (1 article), ENERGY (6 articles), EYHS (5 articles), HBSC 01/02 (5 articles), HBSC 05/06 (3 articles), HBSC 09/10 (2 articles), HBSC 13/14 (1 article), ICAD (3 articles), IDEFICS (3 articles), ISAAC (1 article), ISCOLE (2 articles), Pro Children (2 articles), and Toybox (2 articles). One study reported data of HBSC 01/02, 05/06 and 09/10 together [49], which makes it possible to look at trends in sedentary time over time. Therefore, to describe the variation in population levels of sedentary time, we did not include all articles. If there was more than one article within a larger study reporting exactly the same outcome variable in a similar way in the same sample, only one article was included. These studies included data of all European countries, except for Andorra, Azerbaijan, Bosnia and Herzegovina, Georgia, Liechtenstein, Monaco, Montenegro, San Marino and Serbia.
Fig. 1

Flowchart of the combined review process

Table 1

Study information and sample characteristics of the articles included in the systematic review

Publication

Study

Study design

Quality score (0-1)

Number of EU countries

Number of EU partici-pants

Demographics

Sedentary time assessment method

Reported sedentary time variable

Age range

Gender, girls

SES

Weight status

Biddle et al. (2009) a [ 22 ]

/

CS

0.91

3

623

13-18y

60.4 %

15.0 - 36.1 % low SES

n.r.

Ecological Momentary Assessment diary

min/weekday and min/weekend day technical sedentary behaviours, social sedentary behaviours

Soos et al. (2012) [23]

/

CS

0.83

2

635

13.1-18.0y

60.5 %

n.r.

n.r.

Ecological Momentary Assessment diary

min/day television viewing, doing homework, motorised transport, sitting and talking, computer use, reading, sitting doing nothing, videogames

Soos et al. (2014) [ 24 ]

/

CS

0.86

4

700

11.9-17.9y

57 %

n.r.

n.r.

Ecological Momentary Assessment diary

min/day television viewing, computer use, playing computer games, telephone use, motorised transport, sitting and talking, doing homework, reading

Cinar & Murtomaa (2008) a [ 25 ]

/

CS

0.77

2

619

10-12y

43.9 - 49.1 %

n.r.

18.7 kg/m2

Child questionnaire

% favorable: <2 h/day television viewing

% unfavorable: >2 h/day television viewing

Hanewinkel et al. (2012) [ 26 ]

/

CS

0.95

6

16551

10-19y

49 %

10 % low SES

n.r.

Child questionnaire

h/schoolday television viewing: % None, % less than 1 h, % 1–2 h, % 3–4 h, % >4 h

Börnhorst et al. (2015) [ 27 ]

COSI

CS

0.95

5

10453

6.0-9.9y

49.4 %

16.5 % par. Master’s degree or higher

26.9 % over-weight

Child questionnaire

h/day television time, computer time, screen-time

Brug et al. (2012) a [ 28 ]

ENERGY

CS

1.00

7

7234

10-12y

52 %

15.7-48.4 % low par. edu.

18.1 - 20.6 kg/m2

Child questionnaire

min/day screen-time, television viewing and computer use (FQ and 24 h-recall)

Brug et al. (2012)a [29]

ENERGY

CS

0.91

7

7307

10-12y

52 %

29-59 % low par. edu.

19.0-19.5 kg/m2

Child questionnaire

min/day screen-time

Fernandez-Alvira et al. (2013) [30]

ENERGY

CS

0.95

7

5284

10-12y

54.3 %

32.5 % low par. edu.

20.4 % over-weight

Child questionnaire

min/day screen-time

van Stralen et al. (2014) [ 31 ]

ENERGY

CS

0.95

5

1025

10-12y

51 %

45 % low par. edu.

19.0 kg/m2

ActiGraph accelerometer

min/school-time sedentary time + percentage of total school-time spent in sedentary activities

Verloigne et al. (2012) [ 32 ]

ENERGY

CS

0.95

5

687

10-12y

53 %

n.r.

19.0 kg/m2

ActiGraph accelerometer

min/day sedentary time

Yildirim et al. (2014) [33]

ENERGY

CS

0.95

5

722

10-12y

53 %

14 % not speaking native language at home

n.r.

ActiGraph accelerometer

min/day sedentary time

Ekelund et al. (2004) [34]

EYHS

CS

1.00

4

1292

9-10y

50.6 %

n.r.

17.2 kg/m2

MTI ActiGraph accelerometer

% sedentary activity per day

Jago et al. (2008) [35]

EYHS

CS

0.95

4

2670

9y and 15y

51.1 %

n.r.

13.1 % over-weight

Child questionnaire

% <2 h, % ≥2 h television viewing after school

% <1 h, % ≥1 h/day computer use

Nilsson et al. (2009) a [ 36 ]

EYHS

CS

1.00

4

1954

9y and 15y

47.9 – 63.2 %

n.r.

n.r.

MTI ActiGraph accelerometer

min/weekday, min/weekend day, min/school-time, min/leisure-time sedentary time

Ortega et al. (2013) a [ 37 ]

EYHS

LT cohort

0.91

2

503

15y and 18y

55.4-56.7 %

27.6-33.3 % mother university (baseline)

16.4 – 17.3 kg/m2 (base-line)

ActiGraph accelerometer

min/day, weekday and weekend day sedentary time

van Sluijs et al. (2008) a [ 38 ]

EYHS

CS

0.95

4

2107

9y and 15y

43.9-54.4 %

6.7-10.8 mean edu./income (3-16)

18.1-19.2 kg/m2

Child questionnaire

% >1 h television before school

% >2 h television after school

% >1 h/day computer use

Janssen et al. (2005) a [ 39 ]

HBSC 01/02

CS

0.95

29

128845

10-16y

47.1 - 53.3 %

n.r.

5.1 - 25.4 % over-weight

Child questionnaire

% high television viewing = >3 h/weekday

% high computer use = >2 h/weekday

Kuntsche et al. (2006) [40]

HBSC 01/02

CS

0.91

5

19877

11y, 13y, 15y

52.6 %

n.r.

n.r.

Child questionnaire

h/weekday and h/weekend day television viewing

Richter et al. (2009)a [41]

HBSC 01/02

CS

0.95

24

76794

13y, 15y

52.2 %

22.7-41.9 % low FAS

n.r.

Child questionnaire

% ≥ 4 h/day television viewing

Vereecken et al. (2006) [42]

HBSC 01/02

CS

0.91

28

148150

11y, 13y, 15y

n.r.

n.r.

n.r.

Child questionnaire

h/day television viewing

HBSC report 2004a [43]

HBSC 01/02

CS

0.73

28

146368

11y, 13y, 15y

51.5 %

27.6 % low FAS

7.1 – 12.1 % pre-obese

Child questionnaire

% ≥4 h/weekday and weekend day television viewing

% ≥3 h/weekday and weekend day computer use

% ≥3 h/weekday and weekend day homework

Haug et al. (2009) a [ 44 ]

HBSC 05/06

CS

1.00

34

187657

11y, 13y, 15y

49.3 %

n.r.

6.3 – 18.5 % pre-obese

Child questionnaire

% less than 2 h/day television viewing, computer games, computer use

Torsheim et al. (2010) [45]

HBSC 05/06

CS

0.91

5

31022 (all 6 countries)

11y, 13y, 15y

n.r.

n.r.

n.r.

Child questionnaire

h/day of computer use, computer games, television viewing

HBSC report 2008a [46]

HBSC 05/06

CS

0.68

35

188147

11y, 13y, 15y

50.7 %

2-70 % low FAS

13-14 % over-weight

Child questionnaire

% ≥2 h/weekday television viewing, computer use, computer games/game console

Nuutinen et al. (2015) [47]

HBSC 09/10

CS

1.00

3

5402

15y

53 %

n.r.

n.r.

Child questionnaire

h:min/day computer use schooldays

HBSC report 2012a [48]

HBSC 09/10

CS

0.68

35

178531

11y, 13y, 15y

51 %

2 %-42 % low FAS

10-18 % over-weight

Child questionnaire

% ≥ 2 h/weekday of television viewing

Bucksch et al. (2016) a [ 49 ]

HBSC 01/02, HBSC 05/06, HBSC 09/10

CS

0.82

24

443821 (total sample)

11y, 13y, 15y

51.2-51.4 %

n.r.

n.r.

Child questionnaire

h/weekday and weekend day television viewing, computer use

(total sample)

HBSC report 2016 a [ 50 ]

HBSC 13/14

CS

0.64

36

199316

11y, 13y, 15y

50.7 %

38-76 FAS score (0-100)

15 % over-weight

Child questionnaire

% ≥ 2 h/weekday of television viewing

% ≥ 2 h/weekday of computer use

≥2 h/weekday of playing games

Atkin et al. (2014) a [ 51 ]

ICAD

Pooled data (CS and LT)

0.82

5

5474

8-17y

48.9-56.7 %

4.8-52.6 % mother university

9.4-24.0 % over-weight

Child or parental questionnaire

% ≥ 2/day screen time

Ekelund et al. (2012) a [ 52 ]

ICAD

Pooled data (CS and LT)

0.91

7

15614

4-18y

51.6 %

n.r.

19.1-19.4 kg/m2

ActiGraph accelerometer

min/day sedentary time

Hildebrand et al. (2015) [53]

ICAD

Pooled data (CS and LT)

0.91

6

10367

6-18y

53 %

n.r.

15.9 % over-weight; 4.8 % obese

ActiGraph accelerometer

min/day sedentary time

Hense et al. (2011) [ 54 ]

IDEFICS

CS

0.91

8

8542

2-9y

49.2 %

27.2 % low SES

20.2 % over-weight

Parental questionnaire

h/day screen-time. % not at all, % <0.5 h, % 0.5-1 h, % 1-2 h, % 2-3 h, % >3 h

Hunsberger et al. (2012)a [55]

IDEFICS

CS

0.86

8

12720

2-9y

47.7-51.4 %

1.2 – 30.8 % low edu. household

7.7 – 41.9 % over-weight

Parental questionnaire

% <1 h/day screen-time

Kovàcs et al. (2015) [56]

IDEFICS

CS

0.95

16

16228

2-9.9y

49.1 %

10.7 % low edu. level

Mean BMI z-score: 0.33

Parental questionnaire

% <1 h/day screen-time (pre-schoolers)

% <2 h/day screen-time (school children)

Mitchell et al. (2013) [ 57 ]

ISAAC

CS

0.86

6-7y: 6

6-7ys: 33901

6-7y and 13-14y

n.r.

n.r.

n.r.

Child questionnaire

h/day television viewing: % < 1 h, % 1-3 h, % 3-5 h, % > 5 h

13-14y: 7

13-14y: 61954

Katzmaryk et al. (2015)a [58]

ISCOLE

CS

0.95

3

1664

9-11y

53.8-55.9 %

n.r.

17.7-19.5 kg/m2

ActiGraph accelerometer

min/day sedentary time

LeBlanc et al. (2015) a [ 59 ]

ISCOLE

CS

0.95

3

1496

9-11y

53.1-57.2 %

21.1-73.2 % high par. edu.

24.3-45.7 % over-weight

ActiGraph accelerometer and child questionnaire

h/day sedentary time

h/day screen-time

% ≥ 2 h/day of screen-time

Klepp et al. (2007) a [ 60 ]

Pro Children

CS

1.00

9

12773

8.8-13.8y

49.8 %

71.6 - 82.1 % not in social class I-II

n.r.

Child questionnaire

h/day television viewing

te Velde et al. (2007) [ 61 ]

Pro Children

CS

0.95

9

12538

8.8-13.8y

50.1 %

n.r.

n.r.

Child questionnaire

% <2 h/day television viewing

% >1 h/day computer use

De Craemer et al. (2015) [ 62 ]

Toybox

CS

0.95

6

8117

3.5-5.5y

47 %

n.r.

n.r.

Parental questionnaire

min/weekday and weekend day television viewing, computer use, quiet play

% <1 h/day screen-time weekday and weekend day

van Stralen et al. (2012) a [ 63 ]

ToyBox

Pooled data (CS)

0.91

5

6097

4-7y

47.4 - 52.0 %

n.r.

15.9 – 16.8 kg/m2

Parental questionnaire

h/day television viewing, % ≥ 2 h/day of television viewing, h/day screen-time, min/day sedentary time (sedentary play-time + screen-time)

COSI WHO European Childhood Obesity Surveillance Initiative, ENERGY EuropeaN Energy balance Research to prevent excessive weight Gain among Youth, EYHS European Youth Heart Study, HBSC Health Behaviour in School-aged Children, ICAD International Children’s Accelerometer Database, IDEFICS Identification and prevention of Dietary and lifestyle induced health Effects In Children and infantS, ISAAC International Study of Asthma and Allergies in Childhood, ISCOLE The International Study of Childhood Obesity, Lifestyle and the Environment, CS cross-sectional, LT longitudinal, n.r. not reported, SES socio-economic status, par. edu. parental education, inc. income, FAS Family Affluence Scale, FQ frequency question, aThese articles only presented stratified demographics, so the range is reported; articles in bold were included in Tables 2 and 3

Variation in population levels of sedentary time in European children and adolescents

The population levels of sedentary time in children (0-12y) and adolescents (13-18y) are presented by country in Tables 2 and 3, respectively. For this research question, 24 articles were included. In Table 1, these 24 studies are indicated in bold. The first column of both Tables 2 and 3 shows how the specific type of sedentary activity (e.g. total sedentary time, TV time) was reported (e.g. percentage or minutes) over a specific time period (e.g. weekend day, after school). To keep the Tables as comparable as possible, we only included values of the total sample, except if an article only reported results for boys and girls separately. Some articles also reported the outcome variable separately for regions within a country. For the HBSC-report that was released in 2016 with data of 2013/2014 [50], the values of the 11-year-olds were included in the Table for children, and the values of the 15-year-olds were included in the Table for adolescents.
Table 2

Levels of sedentary time in children (0-12 years) across European countries

Total sedentary time

Armenia

Albania

Austria

Belgium

Bulgaria

Croatia

Cyprus

Czech Republic

Min, h or %/day

   

478 min(B)33, 511 min(G)33, 232 min64

    

Min or %/weekday

        

Min or %/weekend day

        

Min or %/school time

   

65 %(G)32, 61 %(B)32

    

Min or %/leisure time

        

Television time

        

Min or h/day

  

2.2 h61

116 min(G)29,FQ, 110 min(B)29,FQ, 78 min(G)29,recall, 77 min(B)29,recall, 2.7 h61

1.8 h28, 1.8 h64

  

1.2 h28

Min or h/weekday

   

67 min63

79 min63

   

Min or h/weekend day

   

116 min63

131 min63

   

% >1 h before school

        

% >2 h/day

  

36(B)62, 32(G)62

50(B)62, 42(G)62

    

% >2 h/weekday

48(B)51, 47(G)51

51(B)51, 47(G)51

50(B)51, 40(G)51

55(B,FL)51, 54(G,FL)51, 48(B,FR)51, 43(G,FR)51

64(B)51, 66(G)51

49(B)51, 47(G)51

 

62(B)51, 48(G)51

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

        

Computer time

        

Min or h/day

   

89 min(B)29,FQ, 69 min(G)29,FQ, 47 min(B)29,recall, 29 min(G)29,recall

0.7 h28

  

0.5 h28

Min or h/weekday

   

15 min63

28 min63

   

Min or h/weekend day

   

29 min63

44 min63

   

% >1 h/day

  

41(B)62, 16(G)62

35(B)62, 20(G)62

    

% >2 h/weekday

2751

2051

2651

32(FL)51, 28(FR)51

5051

2651

 

3551

Videogames time

        

% >2 h/weekday

2351

2851

3151

33(FL)51, 33(FR)51

5651

2551

 

3751

Total screen-time

        

Min or h/day

   

205 min(B)29,FQ, 178 min(G)29,FQ, 124 min(B)29,recall, 107 min(G)29,recall

2.5 h28

  

1.7 h28

% <1 h/weekday

   

4363

2563

   

% <1 h/weekend day

   

1663

963

   

% >2 h/day

        

% not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h/day

   

2, 13, 32, 28, 15, 1155

  

2, 8, 20, 32, 17, 1255

 

Total sedentary time

Denmark

Estonia

Finland

France

Germany

Greece

Hungary

Min, h or %/day

268 min53, 356 min53

343 min53

8.8 h60

  

526 min(B)33, 510 min(G)33,

487 min(B)33, 475 min(G)33

Min or %/weekday

311 min(B)37, 309 min(G)37

277 min(B)37, 307 min(G)37

     

Min or %/weekend day

299 min(B)37, 280 min(G)37

239 min(B)37, 257 min(G)37

     

Min or %/school time

115 min(B)37, 128 min(G)37

122 min(B)37, 138 min(G)37

   

61 %(B)32, 66 %(G)32

65 %(B)32, 70 %(G)32

Min or %/leisure time

152 min(B)37, 136 min(G)37

132 min(B)37, 146 min(G)37

     

Television time

       

Min or h/day

2.2 h61

    

126 min(B)29,FQ, 120 min(G)29,FQ, 99 min(B)29,recall, 89 min(G)29,recall, 2.2 h64

123 min(B)29,FQ, 116 min(G)29,FQ, 90 min(B)29,recall, 85 min(G)29, recall

Min or h/weekday

    

43 min63

89 min63

 

Min or h/weekend day

    

65 min63

134 min63

 

% >1 h before school

439

1439

     

% >2 h/day

38(B)62, 32(G)62

 

1526

    

% >2 h/weekday

1539, 60(B)51, 49(G)51

4239, 61(B)51, 56(G)51

58(B)51, 55(G)51

50(B)51, 39(G)51

45(B)51, 36(G)51

53(B)51, 45(G)51

47(B)51, 40(G)51

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

 

9, 58, 24, 858

    

17, 63, 14, 558

Computer time

       

Min or h/day

     

88 min(B)29,FQ, 60 min(G)29,FQ, 55 min(B)29,recall, 33 min(G)29,recall

110 min(B)29,FQ, 82 min(G)29,FQ, 75 min(B)29,recall, 46 min(G)29,recall

Min or h/weekday

    

9 min63

18 min63

 

Min or h/weekend day

    

15 min63

30 min63

 

% >1 h/day

1539, 39(B)62, 13(G)62

1639

     

% >2 h/weekday

4051

3751

3351

2951

2751

2551

2751

Videogames time

       

% >2 h/weekday

5351

4351

3051

3351

2551

2851

3451

Total screen-time

       

Min or h/day

  

2.760

 

0.7 h64

214 min(B)29,FQ, 179 min(G)29,FQ, 155 min(B)29,recall, 122 min(G)29,recall

233 min(B)29,FQ, 198 min(G)29,FQ, 166 min(B)29,recall, 131 min(G)29,recall

% <1 h/weekday

    

7163

2963

 

% <1 h/weekend day

    

5263

1263

 

% >2 h/day

3452, 4752

6252

5760

    

% not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h/day

 

1, 6, 19, 24, 18, 3255

  

4, 12, 26, 26, 14, 1355

 

4, 15, 27, 25, 15, 1255

Total sedentary time

Iceland

Ireland

Italy

Latvia

Lithuania

Luxembourg

Malta

Moldova

Netherlands

Min, h or %/day

        

447 min(B)33, 457 min(G)33

Min or %/weekday

         

Min or %/weekend day

         

Min or %/school time

        

65 %(B)32, 68 %(G)32

Min or %/leisure time

         

Television time

         

Min or h/day

2.0 h61

   

1.8 h28

   

116 min(B)29, FQ, 104 min(G)29, FQ, 83 min(B)29, recall, 67 min(G)29, recall, 2.7 h61

Min or h/weekday

         

Min or h/weekend day

         

% >1 h before school

         

% >2 h/day

35(B)62, 23(G)62

       

50(B)38, 46(G)38

% >2 h/weekday

40(B)51, 30(G)51

46(B)51, 42(G)51

47(B)51, 40(G)51

63(B)51, 56(G)51

59(B)51, 54(G)51

44(B)51, 37(G)51

53(B)41, 41(G)51

54(B)51, 53(G)51

61(B)51, 61(G)51

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

    

19, 64, 15, 258

    

Computer time

         

Min or h/day

    

0.9 h28

   

106 min (B)29,FQ, 81 min (G)29,FQ, 71 min(B)29,recall, 45 min(G)29,recall

Min or h/weekday

         

Min or h/weekend day

         

% >1 h/day

36(B)62, 12(G)62

       

53(B)62, 26(G)62

% >2 h/weekday

3151

2951

2751

3851

2651

2751

3551

3151

4251

Videogames time

         

% >2 h/weekday

3951

3151

3251

3951

4051

2951

4251

3651

4951

Total screen-time

         

Min or h/day

    

2.6 h28

   

223 min(B)29,FQ, 185 min(G)29,FQ, 153 min(B)29,recall, 112 min(G)29,recall

% <1 h/weekday

         

% <1 h/weekend day

         

% >2 h/day

         

% not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h/day

  

2, 8, 20, 27, 19, 2455

      

Total sedentary time

Norway

Poland

Portugal

Romania

Russian Federation

Slovakia

Slovenia

Min, h or %/day

325 min53

 

367 min53, 9.2 h60

    

Min or %/weekday

298 min(B)37, 314 min(G)37

 

318 min(B)37, 344 min(G)37

    

Min or %/weekend day

289 min(B)37, 280 min(G)37

 

269 min(B)37, 279 min(G)37

    

Min or %/school time

128 min(B)37, 140 min(G)37

 

146 min(B)37, 153 min(G)37

    

Min or %/leisure time

137 min(B)37, 138 min(G)37

 

153 min(B)37, 169 min(G)37

    

Television time

       

Min or h/day

105 min(B)29,FQ, 97 min(G)29,FQ, 72 min(B)29,recall, 62 min(G)29,recall, 2.2 h61

 

1.3 h28, 2.7 h61

   

120 min(B)29,FQ, 108 min(G)29,FQ, 78 min(B)29,recall, 68 min(G)29,recall

Min or h/weekday

 

71 min63

     

Min or h/weekend day

 

116 min73

     

% >1 h before school

939

 

1539

    

% >2 h/day

38(B)62, 35(G)62

 

49(B)62, 42(G)62

    

% >2 h/weekday

2539, 46(B)51, 41(G)51

56(B)51, 49(G)51

3139, 52(B)51, 45(G)51

67(B)51, 56(G)51

57(B)51, 52(G)51

59(B)51, 54(G)51

49(B)51, 40(G)51

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

 

18, 69, 11, 3(Krakow)58; 11, 73 12, 3(Poznan)58

13, 58, 23, 658

    

Computer time

       

Min or h/day

91 min(B)29,FQ, 71 min(G)29,FQ, 60 min(B)29,recall, 40 min(G)29,recall

 

0.5 h28

   

93 min(B)29,FQ, 64 min(G)29,FQ, 52 min(B)29,recall, 33 min(G)29,recall

Min or h/weekday

 

16 min63

     

Min or h/weekend day

 

32 min63

     

% >1 h/day

2739, 24(B)62, 10(G)62

 

2739, 40(B)62, 17(G)62

    

% >2 h/weekday

3451

3551

2451

3551

4251

4051

2551

Videogames time

       

% >2 h/weekday

3151

3351

2551

4451

4251

4351

2451

Total screen-time

       

Min or h/day

196 min(B)29,FQ, 168 min (G)29,FQ, 132 min (B)29,recall, 101 min (G)29,recall

 

1.8 h28, 2.3 h60

   

213 min(B)29, FQ, 174 min(G)29, FQ, 131 min(B)29, recall, 100 min(G)29, recall

% <1 h/weekday

 

3763

     

% <1 h/weekend day

 

1663

     

% >2 h/day

4952

 

6452, 4960

    

% not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h/day

       

Total sedentary time

Spain

Sweden

Switzerland

Macedonia

Turkey

Ukraine

UK

Min, h or %/day

  

467 min(B)33, 498 min(G)33, 236 min53, 278 min53

   

356 min53, 362 min53, 352 min53, 192 min(SC)53, 8.3 h60

Min or %/weekday

       

Min or %/weekend day

       

Min or %/school time

       

Min or %/leisure time

       

Television time

       

Min or h/day

109 min(B)29,FQ, 97 min(G)29,FQ, 77 min(B)29,recall, 64 min(G)29,recall, 2.2 h61

1.3 h28, 2.1 h61

     

Min or h/weekday

66 min63

      

Min or h/weekend day

122 min63

      

% >1 h before school

       

% >2 h/day

37(B)62, 31(G)62, 864

32(B)62, 31(G)62

  

2826

  

% >2 h/weekday

43(B)51, 30(G)51

58(B)51, 51(G)51

32(B)51, 29(G)51

46(B)51, 43(G)51

 

52(B)51, 46(G)51

51(B,ENG)51, 51(G,ENG)51, 60(B,SC)51, 51(G,SC)51, 62(B,WAL)51, 53(G,WAL)51

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

24, 62, 12, 2(A Coruña)58;

27, 59, 11, 3(Asturias)58;

19, 59, 19, 3(Barcelona)58;

34, 54, 10, 2(Bilbao)58;

15, 63, 19, 4(Cartagena)58;

18, 61, 18, 3(Madrid)58;

22, 61, 14, 2(Valencia)58

      

Computer time

       

Min or h/day

85 min(B)29,FQ, 63 min(G)29,FQ, 45 min(B)29,recall, 25 min(G)29,recall

0.6 h28

     

Min or h/weekday

13 min63

      

Min or h/weekend day

31 min63

      

% >1 h/day

22(B)62, 15(G)62

35(B)62, 18(G)62

     

% >2 h/weekday

2251

4051

1851

3651

 

3351

 

Videogames time

       

% >2 h/weekday

2351

4451

2051

3451

 

3351

41(ENG)51, 51(SC)51, 49(WAL)51

Total screen-time

      

41(ENG)51, 44(SC)51, 50(WAL)51

Min or h/day

193 min(B)29,FQ, 160 min(G)29,FQ, 122 min(B)29,recall, 89 min(G)29,recall

1.9 h28

    

2.9 h60

% <1 h/weekday

4463

      

% <1 h/weekend day

1263

      

% >2 h/day

      

47(ENG)52, 59(ENG)52, 6860

% not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h/day

6, 22, 28, 26, 12, 655

      

This table displays a summary of the results reported in the articles included in the systematic review; B boys, G girls, min minutes, h hours, FQ usual frequency question, FL Flemish part of Belgium, FR French part of Belgium, ENG England, SC Scotland, WAL Wales; references are displayed in superscript to avoid confusion with the levels of sedentary time

Table 3

Levels of sedentary time in adolescents (13-18 years) across European countries

Total sedentary time

Albania

Armenia

Austria

Belgium

Bulgaria

Croatia

Czech Republic

 Min or %/day

       

 Min or %/weekday

       

 Min or %/weekend day

       

 Min or %/school time

       

 Min or %/leisure time

       

Television time

       

 Min or h/day

       

 Min or h/weekday

   

2.6-2.5-2.3 h(B,FL)50, 2.3-2.4-2.2 h(G,FL)50,

2.2-2.2-2.0 h(B,FR)50, 2.1-1.9-1.8 h(G,FR)50

 

3.0-3.0-2.7 h(B)50,

2.7-2.8-2.6 h(G)50

2.8-2.5-2.3 h(B)50,

2.5-2.3-2.2 h(G)50

 Min or h/weekend day

   

3.7-3.4-3.2 h(B,FL)50, 3.1-3.2-3.1 h(G,FL)50,

3.5-3.4-3.2(B,FR)50, 3.2-3.1-3.1 h(G,FR)50

 

3.9-3.5-3.3 h(B)50, 3.7-3.4-3.2 h(G)50

3.2-3.2-3.0 h(B)50, 2.9-2.9-2.7 h(G)50

 % >2 h/day

  

38(B)45, 33(G)45

40(B,FL)45, 40(G,FL)45, 33(B,FR)45, 26(G,FR)45

60(B)45, 66(G)45

44(B)45, 50(G)45

42(B)45, 38(G)45

 % >2 h/weekday

73(B)51, 75(G)51

73(B)51, 66(G)51

54(B)51, 57(G)51

61(B,FL)51, 59(G,FL)51, 64(B,FR)51, 55(G,FR)51

70(B)51, 72(G)51

66(B)51, 59(G)51

65(B)51, 59(G)51

 % >3 h/weekday

  

3140

40(FL)40, 34(FR)40

 

5340

4740

 % <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

   

9, 39, 31, 2058

   

 % ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

       

Computer time

       

 Min or h/day

       

 Min or h/weekday

   

1.4-3.3-3.2 h(B,FL)50, 0.9-2.5-2.5 h(G,FL)50,

1.4-2.9-2.8 h(B;FR)50, 0.7-2.4-2.4 h(G,FR)50

 

1.2-2.7-3.8 h(B)50,

0.5-1.6-2.9 h(G)50

1.6-3.2-4.0 h(B)50,

0.7-1.9-3.0 h(G)50

 Min or h/weekend day

   

2.3-4.7-4.7 h(B,FL)50, 1.4-3.4-3.5 h(G,FL)50,

2.5-5.1-4.9 h(B,FR)50, 1.2-4.0-4.2 h(G,FR)50

 

1.9-3.7-5.0 h(B)50,

0.9-2.2-3.9 h(G)50

1.9-4.0-4.8 h(B)50,

0.8-2.4-3.6 h(G)50

 % >1 h/day

       

 % >2 h/day

  

20(B)45, 15(G)45

23(B,FL)45, 23(G,FL)45, 17(B,FR)45, 15(G,FR)45

30(B)45, 24(G)45

12(B)45, 10(G)45

14(B)45, 14(G)45

 % >2 h/weekday

5051

4851

2540, 5351

26(FL)40, 22(FR)40, 60(FL)51, 60(FR)51

6951

2040, 5751

2640, 6551

Videogames time

       

 Min or h/day

       

 % >2 h/day

  

28(B)45, 12(G)45

22(B,FL)45, 8(G,FL)45, 23(B,FR)45, 15(G,FR)45

44(B)45, 18(G)45

25(B)45, 5(G)45

31(B)45, 7(G)45

 % >2 h/weekday

4051

3551

3651

32(FL)51, 49(FR)51

5351

3251

4251

Total screen-time

       

 Min or h/day

       

 Min or h/weekday

       

Total sedentary time

Denmark

Estonia

Finland

France

Germany

Greece

 Min or %/day

268 min53, 356 min53

506 min(B)38, 496 min(G)38, 343 min53

    

 Min or %/weekday

454 min(B)37, 457 min(G)37

388 min(B)37, 344 min(G)37, 526 min(B)38, 521 min(G)38

    

 Min or %/weekend day

412 min(B)37, 412 min(G)37

331 min(B)37, 367 min(G)37, 459 min(B)38, 434 min(G)38

    

 Min or %/school time

205 min(B)37, 218 min(G)37

186 min(B)37, 227 min(B)37

    

 Min or %/leisure time

205 min(B)37, 191 min(G)37

168 min(B)37, 187 min(B)37

    

Television time

      

 Min or h/day

      

 Min or h/weekday

2.6-2.4-2.4 h(B)50,

2.5-2.3-2.2 h(G)50

3.4-2.8-2.4(B)50,

3.0-2.7-2.4 h(G)50

2.3-2.0-2.0 h(B)50,

2.3-1.9-1.8 h(G)50

2.3-2.3-2.1 h(B)50,

2.1-2.1-2.0 h(G)50

2.4-2.3-2.1 h(B)50,

2.2-2.1-2.0 h(G)50

2.5-2.7-2.7 h(B)50,

2.1-2.8-2.5 h(G)50

 Min or h/weekend day

3.3-3.2-3.2 h(B)50,

3.1-3.0-3.0 h(G)50

4.0-3.5-3.3(B)50,

3.9-3.5-3.2 h(G)50

3.3-2.8-2.8 h(B)50,

3.1-2.7-2.7 h(G)50

3.2-3.2-3.0 h(B)50,

3.0-2.9-2.9 h(G)50

3.4-3.5-3.3 h(B)50,

3.0-3.1-3.0 h(G)50

3.5-3.6-3.6 h(B)50,

3.3-3.6-3.5 h(G)50

 % >1 h before school

40(B)45, 36(G)45

51(B)45, 50(G)45

28(B)45, 27(G)45

37(B)45, 32(G)45

36(B)45, 33(G)45

48(B)45, 53(G)45

 % >2 h/day

      

 % >2 h/weekday

71(B)51, 68(G)51

59(B)51, 57(G)51

61(B)51, 52(G)51

62(B)51, 58(G)51

66(B)51, 60(G)51

71(B)51, 65(G)51

 % >3 h/weekday

4540

6340

4040

3440, 6451

3940

3840

 % <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

 

4, 28, 40, 2858

5, 39, 37, 1958

   

 % ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

    

25, 52, 17, 627

 

Computer time

      

 Min or h/day

      

 Min or h/weekday

1.9-3.6-4.3 h(B)50,

1.8-4.4-4.5 h(B)50,

1.4-3.2-3.4 h(B)50,

1.0-2.7-3.3 h(B)50,

1.5-3.2-3.2 h(B)50,

1.2-2.6-3.7 h(B)50,

0.7-2.1-2.9 h(G)50

0.9-3.0-3.5 h(G)50

0.6-2.0-2.5 h(G)50

0.6-1.9-2.6 h(G)50

0.7-2.2-2.6 h(G)50

0.5-1.1-2.3 h(G)50

 Min or h/weekend day

2.3-4.4-5.4 h(B)50,

2.3-5.5-5.7 h(B)50,

2.0-4.2-4.7 h(B)50,

1.5-4.1-4.9 h(B)50,

2.0-4.7-4.8 h(B)50,

1.9-4.2-5.5 h(B)50,

0.8-2.5-3.4 h(G)50

1.1-3.8-4.4 h(G)50

0.8-2.7-3.5 h(G)50

0.9-2.9-3.9 h(G)50

1.0-3.0-3.7 h(G)50

0.8-1.8-3.7(G)50

 % >1 h/day

      

 % >2 h/day

20(B)45, 17(G)45

32(B)45, 30(G)45

17(B)45, 17(G)45

16(B)45, 16(G)45

19(B)45, 17(G)45

10(B)45, 4(G)45

 % >2 h/weekday

2940, 6751

3240, 7251

2340, 5951

1640

2540, 6651

2140, 5951

Videogames time

      

 Min or h/day

      

 % >2 h/day

32(B)45, 8(G)45

41(B)45, 14(G)45

24(B)45, 6(G)45

20(B)45, 6(G)45

25(B)45, 10(G)45

26(B)45, 6(G)45

 % >2 h/weekday

4251

4151

2951

3851

5051

3851

Total screen-time

      

 Min or h/day

      

 Min or h/weekday

      

Total sedentary time

Hungary

Iceland

Ireland

Italy

Latvia

Lithuania

 Min or %/day

      

 Min or %/weekday

      

 Min or %/weekend day

      

 Min or %/school time

      

 Min or %/leisure time

      

Television time

      

 Min or h/day

100 min25

     

 Min or h/weekday

2.4-2.3-2.2 h(B)50,

2.2-2.1-2.1 h(G)50

  

2.3-2.3-2.1 h(B)50,

2.5-2.2-2.0 h(G)50

3.4-3.0-2.5 h(B)50,

2.9-2.8-2.5 h(G)50

 

 Min or h/weekend day

4.0-3.7-3.6 h(B)50,

3.9-3.6-3.5 h(G)50

  

2.6-2.6-2.6 h(B)50,

2.6-2.4-2.4 h(G)50

4.4-3.6-3.2 h(B)50,

4.1-3.5-3.2 h(G)50

 

 % >2 h/day

40(B)45, 36(G)45

36(B)45, 29(G)45

 

36(B)45, 37(G)45

  

 % >2 h/weekday

62(B)51, 58(G)51

58(B)51, 54(G)51

56(B)51, 54(G)51

59(B)51, 52(G)51

68(B)51, 67(G)51

58(B)51, 58(G)51

 % >3 h/weekday

3940

 

3840

4340

6340

5740

 % <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

7, 48, 32, 1458

    

12, 51, 26, 1158

 % ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

 

29, 55, 13, 327

 

20, 48, 23, 927

  

Computer time

      

 Min or h/day

8 min25

     

 Min or h/weekday

1.4-3.0-3.7 h(B)50,

0.7-1.8-2.6 h(G)50

  

1.1-2.3-3.1 h(B)50,

0.7-1.4-2.7 h(G)50

1.4-3.6-3.9 h(B)50,

0.7-2.4-2.8 h(G)50

 

 Min or h/weekend day

2.4-5.2-6.2 h(B)50,

1.2-3.2-4.5 h(G)50

  

1.3-2.7-3.8 h(B)50,

0.8-1.6-3.3 h(G)50

2.0-4.3-4.8 h(B)50,

1.0-2.9-3.5 h(G)50

 

 % >1 h/day

      

 % >2 h/day

18(B)45, 12(G)45

26(B)45, 23(G)45

 

9(B)45, 8(G)45

  

 % >2 h/weekday

2340, 5851

6151

6151

2040, 5551

2740, 6551

2340, 4651

Videogames time

      

 Min or h/day

26 min25

     

 % >2 h/day

24(B)45, 8(G)45

27(B)45, 3(G)45

 

17(B)45, 4(G)45

  

 % >2 h/weekday

4451

4051

3051

4151

3951

4851

Total screen-time

      

 Min or h/day

156 min(B)23, 114 min(G)23

     

 Min or h/weekday

282 min(B)23, 192 min(G)23

     

Total sedentary time

Luxembourg

Moldova

Malta

Netherlands

Norway

Poland

Portugal

 Min or %/day

    

325 min55

 

367 min55

 Min or %/weekday

    

445 min(B)37, 466 min(G)37

 

411 min(B)37, 435 min(G)37

 Min or %/weekend day

    

385 min(B)37, 402 min(G)37

 

344 min(B)37, 351 min(G)37

 Min or %/school time

    

206 min(B)37, 228 min(G)37

 

206 min(B)37, 217 min(G)37

 Min or %/leisure time

    

189 min(B)37, 190 min(G)37

 

183 min(B)37, 191 min(G)37

Television time

       

 Min or h/day

       

 Min or h/weekday

   

2.8-3.0-2.8 h(B)50,

2.4-2.7-2.6 h(G)50

2.7-2.1-2.0 h(B)50,

2.6-2.2-2.0 h(G)50

3.0-2.6-2.5 h(B)50,

2.6-2.4-2.3 h(G)50

2.8-3.0-2.5 h(B)50,

2.9-3.0-2.5 h(G)50

Min or h/weekend day

   

3.6-3.4-3.2 h(B)50,

3.3-3.3-3.1 h(G)50

3.6-3.0-2.9 h(B)50,

3.3-2.9-2.9 h(G)50

4.0-3.8-3.4 h(B)50,

3.7-3.7-3.4 h(G)50

3.9-4.0-3.8 h(B)50,

3.8-4.0-3.9 h(G)50

 % >2 h/day

32(B)45, 28(G)45

  

50(B)45, 44(G)45

 

55(B)45, 41(G)45

54(B)45, 56(G)45

% >2 h/weekday

66(B)51, 61(G)51

73(B)51, 77(G)51

65(B)51, 54(G)51

73(B)51, 75(G)51

63(B)51, 61(G)51

62(B)51, 64(G)51

55(B)51, 51(G)51

% >3 h/weekday

  

4340

4540

4840

5340

5240

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

     

9, 46, 29, 17(Krakow)58;

8, 54, 27, 12(Poznan)58

11, 37, 30, 22(Funchal)58;

5,36, 36, 23(Lisbon)58;

7, 36, 34, 23(Portimao)58;

8, 45, 30, 18(Porto)58

% ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

   

24, 57, 17, 227

 

19, 49, 24, 827

 

Computer time

       

Min or h/day

       

Min or h/weekday

   

1.7-4.6-4.5 h(B)50,

1.9-3.1-3.3 h(B)50,

1.6-4.2-4.8 h(B)50,

1.5-3.8-3.8 h(B)50,

1.0-3.2-3.4 h(G)50

0.8-2.2-2.5 h(G)50

0.8-2.2-3.2 h(G)50

0.7-2.6-2.8 h(G)50

Min or h/weekend day

   

2.4-5.1-4.9 h(B)50,

1.4-3.7-3.6 h(G)50

2.3-4.1-4.1 h(B)50,

1.0-2.8-2.8 h(G)50

2.5-6.0-6.5 h(B)50,

1.3-3.4-4.7 h(G)50

2.2-5.2-5.9 h(B)50,

1.0-3.4-4.3 h(G)50

% >1 h/day

    

26.812

 

29.730

% >2 h/day

18(B)45, 17(G)45

 

31(B)45, 31(G)45

36(B)45, 35(G)45

 

30(B)45, 21(G)45

23(B)45, 22(G)45

% >2 h/weekday

6751

6651

2040, 6951

3140, 7851

3140, 7451

3240, 7051

2540, 4951

Videogames time

       

Min or h/day

       

% >2 h/day

21(B)45, 9(G)45

  

37(B)45, 10(G)45

 

36(B)45, 8(G)45

36(B)45, 14(G)45

% >2 h/weekday

4451

4151

5751

5651

4851

3251

3251

Total screen-time

       

Min or h/day

       

Min or h/weekday

       

Total sedentary time

Romania

Russian Federation

Slovakia

Slovenia

Spain

Sweden

Min or %/day

     

486 min(B)38, 482 min(G)38

Min or %/weekday

     

498 min(B)38, 503 min(G)38

Min or %/weekend day

     

455 min(B)38, 430 min(G)38

Min or %/school time

      

Min or %/leisure time

      

Television time

      

Min or h/day

87 min25

 

142 min25

   

Min or h/weekday

 

3.2-2.8-2.5 h(B)50,

2.8-2.8-2.6 h(G)50

 

2.5-2.4-2.1 h(B)50,

2.2-2.1-1.9 h(G)50

2.5-2.2-2.2 h(B)50,

2.4-2.1-2.0 h(G)50

2.3-2.1-2.2 h(B)50,

2.2-2.0-2.1 h(G)50

Min or h/weekend day

 

3.9-3.7-3.2 h(B)50,

3.7-3.7-3.4 h(G)50

 

3.3-3.2-2.9 h(B)50,

2.9-3.0-2.8 h(G)50

3.3-3.0-2.7 h(B)50,

3.2-2.8-2.5 h(G)50

3.2-2.8-3.0 h(B)50,

2.9-2.6-2.8 h(G)50

% >2 h/day

40(B)45, 52(G)45

49(B)45, 50(G)45

57(B)45, 56(G)45

39(B)45, 33(G)45

36(B)45, 33(G)45

 

% >2 h/weekday

73(B)51, 75(G)51

63(B)51, 60(G)51

70(B)51, 69(G)51

59(B)51, 50(G)51

63(B)51, 59(G)51

70(B)51, 67(G)51

% >3 h/weekday

 

5640

4040

 

4340

3740

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

    

12, 52, 26, 11(A Coruña)58; 13, 50, 27, 11(Asturias)58; 10, 44, 31, 16(Barcelona)58; 12, 47, 27, 14(Bilbao)58; 8, 41, 34, 17(Cartagena)58; 9, 45, 32, 14(Madrid)58; 14, 50, 25, 11(San Sebastian)58, 9, 47, 30, 15(Valencia)58; 8, 46, 31, 15(Valladolid)58

 

% ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

      

Computer time

      

Min or h/day

15 min25

 

3 min25

   

Min or h/weekday

 

1.7-2.8-4.3 h(B)50,

0.7-1.8-3.6 h(G)50

 

1.3-3.1-3.4 h(B)50,

0.6-1.9-2.5 h(B)50

1.1-2.2-3.2 h(B)50,

0.7-1.6-2.8 h(G)50

1.8-3.6-4.1 h(B)50,

0.9-2.3-3.1 h(G)50

Min or h/weekend day

 

2.4-3.8-5.6 h(B)50,

1.0-2.6-4.7 h(G)50

 

2.1-4.2-4.6 h(B)50,

1.1-2.7-3.3 h(G)50

1.8-3.7-4.1 h(B)50,

1.1-2.5-3.7 h(G)50

2.3-4.3-5.1 h(B)50,

1.1-2.7-3.7 h(G)50

% >1 h/day

      

% >2 h/day

24(B)45, 16(G)45

12(B)45, 9(G)45

17(B)45, 13(G)45

17(B)45, 16(G)45

11(B)45, 10(G)45

 

% >2 h/weekday

5951

3040, 7051

2340, 6851

5851

2040, 6751

3240, 7451

Videogames time

      

Min or h/day

16 min25

 

23 min25

   

% >2 h/day

45(B)45, 24(F)45

30(M)45, 13(F)45

35(B)45, 11(G)45

26(B)45, 6(G)45

16(B)45, 7(G)45

 

% >2 h/weekday

4651

4251

4751

2751

3951

4651

Total screen-time

      

Min or h/day

125 min(B)23, 111 min(G)23

 

118 min(B)23, 139 min(G)23

   

Min or h/weekday

152 min(B)23, 120 min(G)23

 

252 min(B)23, 196 min(G)23

   

Total sedentary time

Switzerland

Macedonia

Turkey

Ukraine

UK

Min or %/day

    

356 min53, 362 min53, 352 min53

Min or %/weekday

     

Min or %/weekend day

     

Min or %/school time

     

Min or %/leisure time

     

Television time

     

Min or h/day

    

119 min25

Min or h/weekday

1.8-1.6-1.4 h(B)50,

1.7-1.4-1.3 h(G)50

2.8-2.5-2.4 h(B)50,

2.5-2.5-2.4 h(G)50

 

3.6-2.9-2.5 h(B)50,

3.3-3.0-2.6 h(G)50

2.9-2.7-2.5 h(B,SC)50, 2.8-2.5-2.3 h(G,SC)50,

2.9-2.6-2.6 h(B,WAL)50, 2.9-2.5-2.3 h(G,WAL)50

Min or h/weekend day

2.9-2.6-2.5 h(B)50,

2.6-2.4-2.4 h(G)50

3.5-3.5-3.1 h(B)50,

3.3-3.6-3.2 h(G)50

 

4.5-3.7-3.2 h(B)50,

4.5-4.0-3.3 h(G)50

3.4-3.2-3.2 h(B,SC)50, 3.2-2.8-2.9 h(G,SC)50

3.4-3.2-3.2 h(B,WAL)50, 3.5-3.0-2.9 h(G,WAL)50

% >2 h/day

19(B)45, 17(G)45

44(B)45, 45(G)45

43(B)45, 41(G)45

54(B)45, 57(G)45

37(B, ENG)45, 31(G,ENG)45

% >2 h/weekday

58(B)51, 51(G)51

57(B)51, 56(G)51

 

61(B)51, 64(G)51

67(B,ENG)51, 66(G,ENG)51, 72(B,SC)51, 64(G,SC)51, 72(B,WAL)51, 73(G,WAL)51

% >3 h/weekday

2440

4840

 

6640

52(ENG)40, 50(SC)40, 53(WAL)40

% <1 h/day, 1-3 h/day, 3-5 h/day, >5 h/day

 

3, 34, 41, 2358

   

% ≤0.5 h, 1-2 h, 3-4 h, >4 h/schoolday

    

22, 50, 20, 8(SC)27

Computer time

     

Min or h/day

    

11 min25

Min or h/weekday

1.1-2.2-2.3 h(B)50,

0.6-1.4-1.8 h(G)50

1.4-3.0-3.4 h(B)50,

0.8-2.1-3.4 h(G)50

 

1.1-2.6-2.8 h(B)50,

0.4-1.2-2.1(G)50

2.1-3.9-4.5 h(B,SC)50, 1.2-2.8-3.5 h(G,SC)50,

1.7-3.6-4.2 h(B,WAL)50, 1.0-2.8-3.5 h(G,WAL)50

Min or h/weekend day

1.9-3.8-4.0 h(B)50,

1.0-2.4-3.1 h(G)50

2.0-4.9-6.0 h(B)50,

1.2-3.6-5.2 h(G)50

 

1.6-3.7-3.7 h(B)50,

0.5-1.8-2.9 h(G)50

2.5-4.6-5.6(B,SC)50, 1.3-3.2-4.2 h(G,SC)50,

2.2-4.4-5.1 h(B,WAL)50, 1.3-3.3-4.2 h(G,WAL)50

% >1 h/day

     

% >2 h/day

12(B)45, 8(G)45

16(B)45, 13(G)45

18(B)45, 16(G)45

12(B)45, 5(G)45

25(B,ENG)45, 25(G,ENG)45

% >2 h/weekday

1640, 5351

2640, 5551

 

1740, 6451

37(ENG)40, 39(SC)40, 33(WAL)40,

72(ENG)51, 78(SC)51, 72(WAL)51

Videogames time

     

Min or h/day

    

37 min25

% >2 h/day

11(B)45, 3(G)45

26(B)45, 12(G)45

22(B)45, 8(G)45

25(B)45, 8(G)45

25(B,ENG)45, 8(G,ENG)45

% >2 h/weekday

3151

3651

 

4351

45(ENG)51, 54(SC)51, 50(WAL)51

Total screen-time

     

Min or h/day

     

Min or h/weekday

     

This table displays a summary of the results reported in the articles included in the systematic review; B boys, G girls, min minutes, h hours, FL Flemish part of Belgium, FR French part of Belgium, ENG England, SC Scotland, WAL Wales; references are displayed in superscript to avoid confusion with the levels of sedentary time

The data clearly show a large variation in reported outcome variables and assessment methods by article, which makes it difficult to describe the child and adolescent population levels. Despite this large variation, in general, higher values for sedentary time were observed in children and adolescents from more East-European countries as compared to the rest of Europe, especially for television viewing.

Further, large differences were observed between articles from the same country. One study illustrated the large differences that can be observed between assessment methods even within the same study, namely there were differences in television viewing, computer use and total screen-time recorded between the usual frequency and the 24 h-recall question type [28].

To provide a more accessible overview of the results, the bar charts in Fig. 2 display the amount of minutes per day that children spent in watching television across four countries using different assessment methods. Three articles were available [28, 60, 62]: one article had data for the four countries [28] and two articles had data for three out of four countries [60, 62]. In one article [28], television time was assessed by both a usual frequency and 24 h-recall questionnaire. In the article using data from the Toybox study [60], we calculated minutes of television time per day by following formula: ((min/weekday*5) + (min/weekend day*2))/7. The highest levels of television time were observed within the article containing data from the Pro Children study (9-11-year-olds), followed by the article containing usual frequency questionnaire data from the ENERGY study (10-12-year-olds).
Fig. 2

Minutes per day of television viewing in different articles for children from four European countries

Variation in assessment methods and reported sedentary time variables

Table 4 provides an overview of the assessment methods and sedentary time outcome variables used in the retrieved articles. To describe this variation, we have again included all eligible articles (n = 42), as articles from the same European study sometimes reported different outcome variables or reported the same outcome variable differently. Some articles used several assessment methods and/or reported several outcome variables. Most articles used a child questionnaire (n = 25), with others using accelerometers (n = 10). Interview with parents was conducted in one study, and in three other studies adolescents were asked to complete an ecological momentary assessment. Questionnaires were used to assess time spent in domains of sedentary time, whilst accelerometers were used to assess total sedentary time. With regard to the domains of sedentary time, television time was assessed in 24 articles, computer time in 15 articles, total screen-time in 11 articles and total sedentary time in 10 articles. Some articles described a specific time period, such as before (n = 1), during (n = 2) and after school hours (n = 3). The outcome variables were mostly expressed in minutes (n = 16) or hours (n = 11) over a specific time period or the percentage exceeding more than 2 h per day (n = 12).
Table 4

Assessment methods and reported outcome variables in the articles included in the systematic review

 

Number

Reference number

Measurement

 ActiGraph accelerometer (100 cpm cut-point and 10 min non-wear time)

1

EYHS[36]

 ActiGraph accelerometer (100 cpm cut-point and 20 min non-wear time)

6

ENERGY [3133], EYHS [37], ISCOLE [58, 59]

 ActiGraph accelerometer (100 cpm cut-point and 60 min non-wear time)

2

ICAD [52, 53]

 ActiGraph accelerometer (500 cpm cut-point and 10 min non-wear time)

1

EYHS [34]

 Self-administered child questionnaire

25

[25, 26], COSI [27], ENERGY [2830], EYHS [35, 38], HBSC 01/02 [3943], HBSC 05/06 [4446], HBSC 09/10 [4749], HBSC 13/14 [50], ICAD [51], ISAAC [57], ISCOLE [59], Pro Children [60, 61]

 Self-administered parental questionnaire

7

ICAD [51], IDEFICS [5456], ISAAC [57], Toybox [62, 63]

 Parental questionnaire interview

1

Toybox [63]

 Ecological Momentary Assessment Diary

3

[2224]

Child and parental questionnaire: question type

 Usual frequency

28

[26], COSI [27], ENERGY [2830], EYHS [35, 38], HBSC 01/02 [3943], HBSC 05/06 [4446], HBSC 09/10 [4749], HBSC 13/14 [50], ICAD [51], IDEFICS [5456], ISAAC [57], ISCOLE [59], Pro Children [60, 61], Toybox [62]

 Recall

1

ENERGY [28]

 Unknown

2

[25], Toybox [63]

Child and parental questionnaire: answer type

 Questions with answer categories

26

[26], COSI [27], ENERGY [2830], EYHS [35, 38], HBSC 01/02 [3943], HBSC 05/06 [4446], HBSC 09/10 [4749], HBSC 13/14 [50], IDEFICS [5456], ISCOLE [59], Pro Children [60, 61], Toybox [62]

 Questions without answer categories

-

-

 Unknown

4

[25], ICAD [51], ISAAC [57], Toybox [63]

Reported specific sedentary time variable

 Total sedentary time

10

ENERGY [3133], EYHS [34, 36, 37], ICAD [52, 53], ISCOLE [58, 59]

 Television time

24

[2326], COSI[27], ENERGY [28], EYHS [35, 38], HBSC 01/02 [3943], HBSC 05/06 [4446], HBSC 09/10 [48, 49], HBSC 13/14 [50], ISAAC [57], Pro Children [60, 61], Toybox [62, 63]

 Computer time

15

[23, 24], COSI [27], ENERGY [28], EYHS [35, 38], HBSC 01/02 [39, 43], HBSC 05/06 [4446], HBSC 09/10 [47, 49], HBSC 13/14 [50], Toybox [62]

 Videogames time

6

[23, 24], HBSC 05/06 [4446], HBSC 13/14 [50]

 Screen-time

11

[22], COSI [27], ENERGY [2830], ICAD [51], IDEFICS [5456], ISCOLE [59], Toybox [62]

 Homework

3

[23, 24], HBSC 01/02 [43]

 Other sedentary activities

4

[2224], Toybox [62]

Reported time period

 Day

28

[24, 25],COSI [27], ENERGY [2830, 32], EYHS [34, 35, 37, 38], HBSC 01/02 [41, 42], HBSC 05/06 [44, 45], ICAD [5153], IDEFICS [5456], ISAAC [57], ISCOLE [58, 59], Pro Children [60, 61], Toybox [62, 63]

 Weekday

14

[22, 23, 26], EYHS [36, 37], HBSC 01/02 [39, 40, 43], HBSC 05/06 [46], HBSC 09/10 [4749], HBSC 13/14 [50], Toybox [62]

 Weekend day

8

[22, 23], EYHS [36, 37], HBSC 01/02 [40, 43], HBSC 09/10 [49], Toybox [62]

 School time

2

ENERGY [31], EYHS [36]

 Before school

1

EYHS [38]

 After school

3

EYHS [35, 36, 38]

Reported unit

 Minutes

16

[2224], ENERGY [2833], EYHS [36, 37], HBSC 09/10 [47], ICAD [52, 53], ISCOLE [58], Toybox [62]

 Hours

11

COSI [27], EYHS [38], HBSC 01/02 [40, 42], HBSC 05/06 [45], HBSC 09/10 [47, 49], ISAAC [57], ISCOLE [59], Pro Children [60], Toybox [63]

 % of time period

2

ENERGY [31], EYHS [34]

 % >1 hour

5

EYHS [35, 38], IDEFICS [55, 56], Toybox [62]

 % >2 hours

12

[25], EYHS [35, 38], HBSC 01/02 [39], HBSC 05/06 [44, 46], HBSC 09/10 [48], HBSC 13/14 [50], ICAD [51], IDEFICS [56], ISCOLE [59], Pro Children [61]

 % >3 hours

2

HBSC 01/02 [39, 43]

 % >4 hours

2

HBSC 01/02 [41, 43]

 % not at all, <0.5 h, 0.5-1 h, 1-2 h, 2-3 h, >3 h

1

IDEFICS [54]

 % <0.5 h, 1-2 h, 3-4 h, >4 h

1

[26]

 % <1 h, 1-3 h, 3-5 h, >5 h

1

ISAAC [57]

h hours, COSI WHO European Childhood Obesity Surveillance Initiative, ENERGY EuropeaN Energy balance Research to prevent excessive weight Gain among Youth, EYHS European Youth Heart Study, HBSC Health Behaviour in School-aged Children, ICAD International Children’s Accelerometer Database, IDEFICS Identification and prevention of Dietary and lifestyle induced health Effects In Children and infantS, ISAAC International Study of Asthma and Allergies in Childhood, ISCOLE The International Study of Childhood Obesity, Lifestyle and the Environment

Discussion

This systematic review aimed to provide an overview of existing cross-European studies assessing sedentary time in children (0-12y) and adolescents (13-18y), to describe the variation in population levels of sedentary time and to discuss the impact of assessment methods.

Overview of existing cross-European studies

The literature search revealed 42 articles reporting on levels of sedentary time. Thus, the current systematic review included the highest number of eligible articles in comparison with the other three reviews on sedentary time in adults and on physical activity in youth and adults [1618]. Although sedentary time has only received increased attention in the last few years, earlier studies have described children and adolescents’ television and screen-time [64].

Nine articles that were part of the HBSC-studies included the most countries (up to 36), but there were still some countries for which no data were available in cross-European studies. These countries should therefore be included in further European surveillance studies in order to have a complete overview of the sedentary time levels among children and adolescents. Since 38 of 42 articles were cross-sectional, future longitudinal studies could shed light on how sedentary time varies over time in the same population of children and adolescents. However, conducting repeated cross-sectional studies is also of importance in terms of public health to understand trends in sedentary time.

Variation in population levels of sedentary time and impact of assessment methods

The tables with data on the levels of sedentary time in children and adolescents across European countries might be useful for European researchers and policy makers, as they provide an orderly reference work of conducted cross-European studies. One general conclusion that we might draw from the results is that children and adolescents from Eastern-European countries (i.e. the more eastern part of Europe such as Bulgaria, Slovakia, Ukraine) have somewhat higher levels of sedentary time compared to the rest of Europe. However, there are several plausible reasons for the large differences observed between articles. First, different assessment methods were used. Child-specific questionnaires were used in 60 % of the articles and were only designed to measure time spent in domain-specific sedentary activities. Accelerometers were the only assessment methods that measured the total sitting time and were used in 24 % of the articles, probably because greater cost incurred in using accelerometers in large-scale studies. However, as technological advances have made the accelerometers smaller, lighter, and less expensive, it has been argued that the accelerometer has now become feasible for use in large-scale studies. An important remark is that standard procedures to process accelerometer data are then needed [65]. To estimate children’s total sedentary time via accelerometers, sedentary time was measured by summing the recorded epochs during which the average accelerometer counts were equivalent to less than 100 counts per minute, which is the most commonly used threshold for sedentary time measurement [66, 67]. Another assessment method that might also be less feasible to use in large-scale studies is the ecological momentary assessment tool. This method was used in three cross-European articles, but included a rather limited number of participants and countries, as this assessment method brings along a high time burden for participants. Next to variation in assessment methods, the included articles also reported different outcome variables (e.g. television time vs. total screen-time) or reported the same outcome variable differently (e.g. television time expressed in minutes per day vs. expressed in the percentage exceeding the 2 h recommendation). Finally, the amount of sedentary time was observed to substantially vary in individual countries across different articles. Among Estonian female adolescents for example, total sedentary time on a weekday was less than six hours in one article [36] and almost nine hours in another article [37]. These differences might have emerged because of age differences between study samples. In this review, separate tables were designed for children and adolescents, but age differences can still cause the differences in population levels between and within countries, as the amount of sedentary time increases with age [68]. Thus, because of these large methodological differences between studies, we want to emphasise that cross-European comparisons are currently only possible within studies.

Limitations and strengths

This review has some limitations that should be acknowledged. A first limitation is that although the search was performed in several databases in combination with multiple additional search strategies (e.g. back- and forward tracking), there is still a possibility that not all existing studies on this topic were covered. Some articles might not be found in our databases searched or through our search strategy. The use of including only English published data might also contribute to this limitation, although we expect that results of cross-European studies would be published in English. Another possible limitation could be that only cross-European studies were included. Single-country studies may have provided additional information. However, the purpose was to specifically review the literature on cross-country studies so that the results across countries would at least be comparable within articles [15]. This also means that cross-European studies that did not report the outcome separately per country were excluded in the review, such as the HELENA (Healthy lifestyle in Europe by nutrition in adolescence) study [69]. An important strength is the systematic process: there was a written protocol for all four reviews that was agreed upon by all involved researchers and the search, article selection, data extraction and quality assessment were conducted together for all four reviews. Also, each step of the review process has been conducted by two independent researchers with issues being resolved by consulting a third researcher.

Recommendations for the future

This systematic literature review showed that there is a need for harmonisation and standardisation of methods to assess sedentary time in European children and adolescents. The same conclusion was drawn from the other systematic reviews conducted within DEDIPAC for sedentary time in adults and for physical activity in youth and adults [1618]. A possible approach for the future could be to add objective assessment methods in existing large cross-European surveillance systems, such as the HBSC-study. Another approach could be to conduct a pooled analysis on existing data of European children and adolescents (and adults). This is similar as the approach of the International children’s accelerometry database (ICAD) which collected, pooled and reduced individual accelerometer data files using standardised methods to compare the outcome variables across studies [70]. However, it might be difficult to obtain accelerometer data from all European countries, as few countries have population representative accelerometer data. Conducting a pooled analysis on existing questionnaire data would also be difficult, as harmonisation of data from different questionnaires is even more challenging. A final approach could be to set up a new cross-European surveillance system combining objective and self-report methods (for example, accelerometers and questionnaires) to monitor levels of sedentary time and physical activity in children, adolescents and adults.

Conclusion

Generally, higher levels of sedentary time were observed in children and adolescents from Eastern-European countries. There was a large variation in assessment methods and outcome variables across cross-European studies. Questionnaires (child specific) were used most often, probably because of feasibility reasons. These self-report measures mostly measured screen-based activities only, rather than total sedentary time. In sum, to enable cross-European surveillance, there is a need for harmonisation and standardisation of methods to assess sedentary time in European children and adolescents. Such a surveillance system should combine objective and self-report methods.

Abbreviations

B, boys; COSI, WHO European childhood obesity surveillance initiative; ENERGY, EuropeaN energy balance research to prevent excessive weight gain among youth; ENG, England; EYHS, European youth heart study; FG, usual frequency question; FL, Flemish part of Belgium; FR, French part of Belgium; G, girls; h, hour; HBSC, health behaviour in school-aged children; ICAD, International Children’s Accelerometer Database; IDEFICS, identification and prevention of dietary and lifestyle induced health Effects In Children and infantS; ISAAC, International Study of Asthma and Allergies in Childhood; ISCOLE, The International Study of Childhood Obesity, Lifestyle and the Environment; min, minutes; SC, Scotland; SES, socio-economic status; WAL, Wales

Abbreviations

B: 

Boys

COSI: 

WHO European childhood obesity surveillance initiative

ENERGY: 

EuropeaN energy balance research to prevent excessive weight gain among youth

ENG: 

England

EYHS: 

European youth heart study

FG: 

Usual frequency question

FL: 

Flemish part of Belgium

FR: 

French part of Belgium

G: 

Girls

h: 

Hour

HBSC: 

Health behaviour in school-aged children

ICAD: 

International Children’s Accelerometer Database

IDEFICS: 

Identification and prevention of dietary and lifestyle induced health Effects In Children and infantS

ISAAC: 

International Study of Asthma and Allergies in Childhood

ISCOLE: 

The International Study of Childhood Obesity, Lifestyle and the Environment

min: 

Minutes

SC: 

Scotland

SES: 

Socio-economic status

WAL: 

Wales

Declarations

Acknowledgements

Not applicable.

Funding

The preparation of this paper was supported by the DEterminants of DIet and Physical ACtivity (DEDIPAC) knowledge hub. This work is supported by the Joint Programming Initiative ‘Healthy Diet for a Healthy Life’. The funding agencies supporting this work are (in alphabetical order of participating Member State): Belgium: Research Foundation – Flanders; Ireland: The Health Research Board (HRB); The Netherlands: The Netherlands Organisation for Health Research and Development (ZonMw); Norway: The Research Council of Norway, Division for Society and Health.

Availability of data and supporting materials

Not applicable.

Authors’ contributions

MV, AL and LvH conducted the search, article selection, data extraction and quality assessment and drafted the manuscript. JL, IH, IDB, BD, AD, UE, JB, HvdP conceptualised and designed the study. All authors were involved in critically revising the manuscript for important intellectual content and have read and approved the final manuscript.

Competing interests

The authors declare that they have no competing interests.

Consent for publication

Not applicable.

Ethics approval and consent to participate

Not applicable.

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Department of Movement and Sports Sciences, Faculty of Medicine and Health Sciences, Ghent University
(2)
Department of Epidemiology and Biostatistics, VU University Medical Center, EMGO+ Institute for Health and Care Research
(3)
Department of Public Health, Faculty of Medicine and Health Sciences, Ghent University
(4)
Physical activity, Nutrition and Health Research Unit, Department of Movement and Sport Sciences, Faculty of Physical Education and Physical Therapy, Vrije Universiteit Brussel
(5)
TNO Expertise Centre Lifestyle
(6)
Body@Work, EMGO+ Institute for Health and Care Research, VU University Medical Center
(7)
Centre for Physical Activity and Health Research, Department of Physical Education and Sport Sciences, University of Limerick
(8)
Department of Sports Medicine, Norwegian School of Sport Sciences
(9)
Department of Public and Occupational Health, VU University Medical Center, EMGO Institute for Health and Care Research
(10)
Sydney School of Public Health, The Charles Perkins Centre (D17), University of Sydney

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