Jansen, W.

children health weight study income school child status intervention parent behaviour weight status score obesity problem activity sample effect self-reported member rotterdam adolescent scale difference result table education dutch level group prevalence height youth netherland association country cp members gender research sport kipppi questionnaire characteristic intention socio-demographic characteristics pupil population childhood self-reported height model measure energy-balance behaviours health indicators bitsea validity grade market prevention youth health care breakfast transformation origin income advantages body weight perception change socio-demographic question behavior czech republic survey t 2 sample energy-balance well-being competence indicator self-reported weight status advantage reliability perception fitness