Table 1 Criteria for assessing studies’ methodological quality

Study design

Experimental study (e.g., randomized control trial)

4

Case control study

3

Longitudinal study

2

Cross-sectional study

1

Sample size

Large (>300)

3

Medium (>100 and <300)

2

Small (<100)

1

Definition of ACS

Defined

1

Not defined

0

Data analysis

More advanced statistics (e.g., mixed models)

4

Regression/analysis of covariance

3

Bivariate statistics (e.g., ANOVA, Pearson r, t test)

2

Descriptive only (e.g., frequency)

1

Control variable(s)

Included

1

Not included

0

Multicollinearity testing

Tested

1

Not tested/not mentioned

0

Data reliability testing

Reported results, based on other & own data (including reported elsewhere)

3

Reported results, based on own data (including reported elsewhere)

2

Reported results, based on other data

1

Not reported

0

Data validity testing

Reported results, based on other & own data

3

Reported results, based on own data

2

Reported results, based on other data

1

Not reported

0

Participant recruitment

Parent and child pair

2

Parent, child or others (e.g., principals)

1

Participant characteristics

Reported (e.g., child age or grade)

1

Not reported

0

School characteristics

Reported (e.g., size or composition), multiple locations

2

Reported, single location

1

Not reported

0