# Table 1 Description of baseline measurements April-June 2010, study population (adolescents: n = 1348, parents: n = 1348, school managements: n = 14), and response rate

Measurement Who What When Response rate
Questionnaire Adolescents Students filled out an e-survey in a school session with questions about physical activity, health, neighbourhood, school etc. Duration: 30 minutes. During the week when wearing accelerometer in April-June 2010 97.4%
(n = 1313)
Diaries Adolescents Every morning during one week the students filled out a diary with information about active transportation, and use of accelerometer 5 minutes each school day in 1 week (5 weekdays and 2 weekend days) simultaneously with wearing the accelerometer, in April-June 2010 96.6%
(n = 1302)
Physical fitness and anthropometric tests Adolescents Students (without health problems) participated in a physical testing session of 11/2 hour including: body measurements (weight, height, waist circumference), running test, agility test, fitness test Duration 11/2 hour, at the end of the week when wearing accelerometre. April-June 2010 93.9%
(n = 1266)
MTI Actigraph Adolescents Students wore an accelerometer (MTI Actigraph,
GT3X) in 7 days. 5 week days and 2 weekend
days
All day in 1 week (5 weekdays and 2 weekend days) in April-June 2010 88.6%*
(n = 1194)
Questionnaire Parents One parent (mother or father) completed an e-
survey about parental physical activity and health
behaviour, the neighbourhood etc.
Duration: 15 minutes. In April-June 2010 72.6%
(n = 978)
Questionnaire School
management
A person from the school management completed
an e-survey about the school social and physical
environment, school politic etc.
Duration: 10 minutes. In April-June 2010 100%
(n = 14)
1. *Response rate calculated as those wearing accelerometer for at least 9 hours in at least 4 days (time interval 7a m-11 pm. cut out blocks of non wear defined as 20 min of inactivity - consecutive zeroes).