title: An assessment of self-reported physical activity instruments in young people for population surveillance: Project ALPHA.
abstract: BACKGROUND
  The assessment of physical activity is an essential part of understanding patterns and influences of behaviour, designing interventions, and undertaking population surveillance and monitoring, but it is particularly problematic when using self-report instruments with young people. This study reviewed available self-report physical activity instruments developed for use with children and adolescents to assess their suitability and feasibility for use in population surveillance systems, particularly in Europe.
  
  
  METHODS
  Systematic searches and review, supplemented by expert panel assessment.
  
  
  RESULTS
  Papers (n=437) were assessed as potentially relevant; 89 physical activity measures were identified with 20 activity-based measures receiving detailed assessment. Three received support from the majority of the expert group: Physical Activity Questionnaire for Children/Adolescents (PAQ-C/PAQ-A), Youth Risk Behaviour Surveillance Survey (YRBS), and the Teen Health Survey.
  
  
  CONCLUSIONS
  Population surveillance of youth physical activity is strongly recommended and those involved in developing and undertaking this task should consider the three identified shortlisted instruments and evaluate their appropriateness for application within their national context. Further development and testing of measures suitable for population surveillance with young people is required.
authors.affiliation: British Heart Foundation National Centre for Physical Activity & Health, School of Sport, Exercise & Health Sciences, Loughborough University, UK. s.j.h.biddle@lboro.ac.uk
authors.forename: Stuart J H
authors.initials: SJ
authors.lastname: Biddle
authors.forename: Trish
authors.initials: T
authors.lastname: Gorely
authors.forename: Natalie
authors.initials: N
authors.lastname: Pearson
authors.forename: Fiona C
authors.initials: FC
authors.lastname: Bull
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D040343:Behavioral Risk Factor Surveillance System; D002648:Child; D002652:Child Behavior; D005260:Female; D006306:Health Surveys / Q000379:methods*; D006801:Humans; D008297:Male; D009043:Motor Activity; D057566:Self Report