title: Test-retest reliability and construct validity of the ENERGY-child questionnaire on energy balance-related behaviours and their potential determinants: the ENERGY-project.
abstract: BACKGROUND
  Insight in children's energy balance-related behaviours (EBRBs) and their determinants is important to inform obesity prevention research. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed.
  
  
  OBJECTIVE
  To examine the test-retest reliability and construct validity of the child questionnaire used in the ENERGY-project, measuring EBRBs and their potential determinants among 10-12 year old children.
  
  
  METHODS
  We collected data among 10-12 year old children (n = 730 in the test-retest reliability study; n = 96 in the construct validity study) in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC) and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent face-to-face interview was assessed using ICC and percentage agreement.
  
  
  RESULTS
  Of the 150 questionnaire items, 115 (77%) showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Test-retest reliability was moderate for 34 items (23%) and poor for one item. Construct validity appeared to be good to excellent for 70 (47%) of the 150 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 80 items, construct validity was moderate for 39 (26%) and poor for 41 items (27%).
  
  
  CONCLUSIONS
  Our results demonstrate that the ENERGY-child questionnaire, assessing EBRBs of the child as well as personal, family, and school-environmental determinants related to these EBRBs, has good test-retest reliability and moderate to good construct validity for the large majority of items.
authors.affiliation: VU University Medical Center, EMGO Institute for Health and Care Research, Dpt, of Public and Occupational Health, Amsterdam, The Netherlands. a.singh@vumc.nl
authors.forename: Amika S
authors.initials: AS
authors.lastname: Singh
authors.forename: Froydis N
authors.initials: FN
authors.lastname: Vik
authors.forename: Mai J M
authors.initials: MJ
authors.lastname: Chinapaw
authors.forename: Léonie
authors.initials: L
authors.lastname: Uijtdewilligen
authors.forename: Maïté
authors.initials: M
authors.lastname: Verloigne
authors.forename: Juan M
authors.initials: JM
authors.lastname: Fernández-Alvira
authors.forename: Sarolta
authors.initials: S
authors.lastname: Stomfai
authors.forename: Yannis
authors.initials: Y
authors.lastname: Manios
authors.forename: Marloes
authors.initials: M
authors.lastname: Martens
authors.forename: Johannes
authors.initials: J
authors.lastname: Brug
mesh_terms: D002648:Child; D002652:Child Behavior; D003625:Data Collection; D004032:Diet; D004734:Energy Metabolism; D005060:Europe; D015444:Exercise; D005260:Female; D015438:Health Behavior; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D009765:Obesity / Q000517:prevention & control*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*