Table 1 Questionnaire means, standard deviations ( SD ), item kurtosis values, and Mardia’s coefficient of multivariate kurtosis

Participants were asked to rate confidence in their ability to adopt and overcome barriers to healthy eating behaviors. Scale: 1 = Disagree a lot: 6 = Agree a lot.E.g.: “I find it easy to eat at least 3 servings of fruit each day”.

1-6 (7)

4.07 ± (0.81)

−1.06 to 2.38

4.91*

4.25 ± (0.80)

−1.03 to 1.80

2.53

Participants were asked to indicate their intentions to eat healthily, starting with the common stem “In the next 3 months do you intend to…” Scale: 1 = Not at all true of me: 4 = Very true of me. E.g.: “…do you intend to choose low-fat foods and drinks whenever you have the choice?”

1-4 (5)

3.11 ± (0.52)

−0.64 to 0.61

4.87*

3.20 ± (0.55)

−0.54 to 0.90

7.15*

Participants were asked to respond to statements about their mental representation of the physical environment influencing their ability to eat healthy foods. Scale: 1 = Disagree a lot: 6 = Agree a lot. Example item: “At home there are healthy drinks available – e.g. cold water, sugar-free drinks, reduced fat milk”.

1-6 (4)

5.42 ± (0.56)

−0.16 to 2.57

15.01*

5.43 ± (0.58)

0.03 to 3.83

20.97*

Participants were asked to rate the frequency at which they rein- forced their own healthy eating behaviors through setting goals, self-monitoring and strategies for enhancing enjoyment, starting with the common stem “In the past 3 months how often…”. Scale: 1 = Never: 5 = Always. E.g.: “…did you choose reduced-fat options when they were available?”

[21]

1-5 (6)

3.24 ± (0.71)

−0.95 to 0.00

−0.02

3.33 ± (0.74)

−0.93 to −0.31

2.08

Participants were asked to rate the frequency with which family reinforced healthy eating through encouragement, role modeling, and accessibility to healthy foods, starting with the common stem “In the past 3 months how often…”. Scale: 1 = Never: 5 = Always. E.g.: “…did your parents encourage you to eat fruit and/or vegetables?”

[21]

1-5 (5)

4.29 ± (0.54)

−0.39 to 6.02

15.17*

4.30 ± (0.59)

−0.69 to 7.29

22.23*

Participants were asked to respond to statements about various benefits of healthy eating. Scale: 1 = Disagree a lot: 6 = Agree a lot. E.g.: “Healthy eating (e.g. not skipping meals) can help to improve my concentration at school”.

[22, 23]

1-6 (5)

5.33 ± (0.51)

−0.06 to 4.02

19.05*

5.35 ± (0.49)

−0.67 to 6.54

16.15*

Participants were asked to rate personal value placed on each corresponding outcome expectation item for healthy eating. Scale: 1 = Not at all important: 4 = Extremely important E.g.: “How important is improving concentration at school to you?”

1-4 (5)

3.40 ± (0.44)

−0.71 to 1.57

4.32*

3.43 ± (0.45)

−0.70 to 2.18

6.28*