title: Effects of health measurements and health information in youth and young adulthood in dietary intake--20-y study results from the Amsterdam Growth and Health Longitudinal Study.
abstract: BACKGROUND
  The Amsterdam Growth and Health Longitudinal Study (AGAHLS) is a 20 y observational study concerning biological, psychological and lifestyle risk factors for cardiovascular disease and osteoporosis. In the AGAHLS two cohorts can be distinguished: the so-called Multi-Measurement Group (MMG), which received eight repeated measurements, and a Bi-Measurement Group (BMG), which received two measurements, one at the beginning and one at the end of the 20 y period.
  
  
  OBJECTIVE
  In health-related longitudinal research, the outcomes of the study may be influenced by the measurements themselves and the health information provided. It was hypothesized that the repeated measurements and the health information given to the MMG would result in a more healthy dietary intake in comparison to the BMG.
  
  
  METHODS
  The MMG consisted of 164 subjects and the BMG consisted of 90 subjects. At the start of the study, subjects were teenagers of 13-y-old. The hypothesis was tested with use of regression analysis, analysing group differences in mean individual change scores.
  
  
  RESULTS
  Only the MMG showed a significantly larger decrease in the intake of mono- and disaccharides compared to the BMG.
  
  
  CONCLUSIONS
  The effect of the repeated measurements and the health information provided on dietary intake was relatively small, since it was only one out of the 14 nutrients that differed between the MMG and the BMG.
authors.affiliation: Institute for Research in Extramural Medicine (EMGO), Faculty of Medicine, Vrije Universiteit, The Netherlands.
authors.forename: W
authors.initials: W
authors.lastname: de Vente
authors.forename: G B
authors.initials: GB
authors.lastname: Post
authors.forename: J W
authors.initials: JW
authors.lastname: Twisk
authors.forename: H C
authors.initials: HC
authors.lastname: Kemper
authors.forename: W
authors.initials: W
authors.lastname: van Mechelen
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D015331:Cohort Studies; D004032:Diet; D004034:Diet Surveys; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D005247:Feeding Behavior / Q000523:psychology*; D005260:Female; D006293:Health Promotion; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D018977:Micronutrients / Q000008:administration & dosage; D009426:Netherlands
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D018977:Micronutrients