title: Long-term efficacy of a Web-based computer-tailored nutrition education intervention for adults including cognitive and environmental feedback: a randomized controlled trial.
abstract: BACKGROUND
  Unhealthy diets are prevalent in Western countries, especially among low-educated people. To have an effect on health, it is important that dietary changes are sustained over time. This study examines long-term effects of a cognitive and environmental-feedback version of a Web-based computer-tailored (CT) nutrition education intervention targeting fruit, vegetables, high-energy snacks and saturated fat.
  
  
  METHODS
  A randomized controlled trial was conducted with a basic (tailored intervention targeting individual cognitions and self-regulation processes; n = 456), plus (additionally targeting environmental-level factors; n = 459) and control group (generic nutrition information; n = 434). Participants were recruited from the general population and randomly assigned to a study group. Online self-reported questionnaires assessed fruit, vegetable, high-energy snack and saturated fat intake, self-regulation, self-control, and Body Mass Index (BMI) at baseline and nine-months post-intervention. Linear mixed model analyses examined group differences in change over time. Educational differences were examined by 'group X time X education' interaction terms. Effects were examined in the total sample and among participants who did not comply with dietary- or BMI guidelines.
  
  
  RESULTS
  The effects on vegetable intake in the total sample differed according to educational level (p = 02). Among low/moderate-educated participants, the basic version was significantly more effective in increasing vegetable intake than the control program (effect size (ES) = 0.32) and plus version (ES = 0.22). No effects were found for high-educated participants. Self-regulation change was significantly larger in the control group than in the basic (ES = 0.18) and plus (ES = 0.16) group.
  
  
  CONCLUSIONS
  In general, both intervention versions did not result in long-term intervention effects. The exception was an effect of the basic version on self-reported vegetable intake among low/moderate-educated adults in the total sample. More research is needed on how targeting self-regulation processes and environmental-level factors in Web-based CT nutrition education interventions can increase long-term efficacy.
  
  
  BACKGROUND
  Netherlands Trial Registry NTR3396 .
authors.affiliation: Department of Health Promotion, School for Public Health and Primary Care (CAPHRI), Maastricht University, P.O. Box 616, Maastricht, MD, 6200, the Netherlands. linda.springvloet@maastrichtuniversity.nl.
authors.forename: Linda
authors.initials: L
authors.lastname: Springvloet
authors.affiliation: Faculty of Psychology and Educational Sciences, Open University of the Netherlands, P.O. Box 2960, Heerlen, DL, 6401, the Netherlands. lilian.lechner@ou.nl.
authors.forename: Lilian
authors.initials: L
authors.lastname: Lechner
authors.affiliation: Department of Health Promotion, School for Public Health and Primary Care (CAPHRI), Maastricht University, P.O. Box 616, Maastricht, MD, 6200, the Netherlands. hein.devries@maastrichtuniversity.nl.
authors.forename: Hein
authors.initials: H
authors.lastname: de Vries
authors.affiliation: Department of Health Promotion, School for Public Health and Primary Care (CAPHRI), Maastricht University, P.O. Box 616, Maastricht, MD, 6200, the Netherlands. a.oenema@maastrichtuniversity.nl.
authors.forename: Anke
authors.initials: A
authors.lastname: Oenema
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D003071:Cognition; D003194:Computer-Assisted Instruction / Q000379:methods*; D004032:Diet; D004777:Environment; D005246:Feedback; D005247:Feeding Behavior; D005260:Female; D005638:Fruit; D006266:Health Education / Q000379:methods*; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D062410:Snacks; D012959:Socioeconomic Factors; D014675:Vegetables