Table 1.

Description of individual, sociocultural and school-based variables.

Variable	Questionnaire Item	Item(s) Handled	Response Category
Self-efficacy to be physically active	I could be active even… if I have to get up early if my friends want to do something else if I have a lot of work for school if it is hard or difficult	Mean value of four items (Cronbach’s alpha = 0.85)	1 = Strongly disagree, 2 = Partly disagree, 3 = Neither agree nor disagree, 4 = Partly agree, 5 = Strongly agree
Perceived benefits of physical activity	I think physical activity is good because it improves my aerobic condition and health because I am with friends or I meet new people because I get fun out of physical activities because during physical activities, I can show that I am better than others because otherwise I would feel bored because I lose weight and improve my body	Mean value of six items (Cronbach’s alpha = 0.77)
Perceived barriers of physical activity	I am not able to participate in physical activities because I do not have enough time because I do not like it because I am not good at it because I do not have transportation to get there because my parents do not allow me	Mean value of five items (Cronbach’s alpha = 0.75)
Peer modeling of physical activity	How often are your friends physically active?	Single item	1 = Never, 2 = Almost never, 3 = Sometimes, 4 = Often, 5 = Always
Peer co-participation in physical activity	How often are your friends physically active together with you?	Single item
Peer encouragement to be physically active	How often do your friends encourage you to be physically active?	Single item
Parental modeling of physical activity	How often are your parents physically active?	Single item
Parental co-participation in physical activity	How often are your parents physically active together with you?	Single item
Parental encouragement to be physically active	How often do your parents encourage you to be physically active?	Single item
Relationship with classmates	My classmates like being together Most of my classmates are friendly and helpful My classmates accept me as I am	Mean value of three items (Cronbach’s alpha = 0.85)	1 = Strongly disagree, 2 = Partly disagree, 3 = Neither agree nor disagree, 4 = Partly agree, 5 = Strongly agree
Involvement in organising school activities	The pupils in our school are involved in organizing school activities	Single item
Relationship with teachers	My classmates and me have good bonds with the teachers at school	Single item