|- candidate number||2180|
|- NTR Number||NTR738|
|- Date ISRCTN created||22-nov-2006|
|- date ISRCTN requested||8-nov-2006|
|- Date Registered NTR||26-jul-2006|
|- Secondary IDs||N/A |
|- Public Title||Diet in Action. (Voeding in Actie)|
|- Scientific Title||The impact of implementation intentions (II) in changing complex health-related behaviors in order to prevent weight gain: The case of diet. |
|- Healt Condition(s) or Problem(s) studied||No condition, healthy person|
|- Inclusion criteria||1. 18 - 65 years; |
2. motivated to work on weight (prevention of weight gain and/or loosing weight);
3. BMI > 25;
4. sufficient understanding of the Dutch language.
|- Exclusion criteria||Prescribed diet from dietician or physician.
|- mec approval received||yes|
|- multicenter trial||no|
|- Type||2 or more arms, randomized|
|- planned startdate ||1-sep-2005|
|- planned closingdate||24-mei-2006|
|- Target number of participants||487|
|- Interventions||The intervention consisted of a web-based computer-tailored program aiming at reducing calorie intake. In the firs part of the program the most important energy sources in the diet were identified based on the anwers on an extensive food frequency questionnaire and personal feedback about these energy sources and suggestions to change was provided.In the second part of the intervention, respondents had to make implementation intentions (IIs), i.e. specific action plans defining how, where and when to perform a particular action. There were 4 different versions of the 2nd part of the program, participants were randomly allocated by a computer to one the conditions: |
1. IIs to reduce the intake of high calorie products;
2. IIs to replace high calorie products by low calorie products;
3. IIs to increase intake of low calorie products;
4. control group, no II.
Respondents were explosed to the intervention in a laboratory setting. All the intervention materials were provided once.
|- Primary outcome||Height, weight and waist circumference measured by a trained research assistant. Energy intake (total and of specific food groups) measured by a self-administered validated food frequency questionnaire developed by Wageningen University.|
|- Secondary outcome||Psychosocial variables.|
|- Trial web site||N/A|
|- status||inclusion stopped: follow-up|
|- CONTACT FOR PUBLIC QUERIES||MPH Willemieke Kroeze|
|- CONTACT for SCIENTIFIC QUERIES||PhD. Anke Oenema|
|- Sponsor/Initiator ||Erasmus Medical Center, Department of Public Health|
(Source(s) of Monetary or Material Support)
|ZON-MW, The Netherlands Organization for Health Research and Development|
|- Brief summary||In weight management, avoidance of energy dense (i.e. rich in fat and/or sugar) and choosing energy poor, dietary fiber rich foods is advocated. Small modifications in intake of energy-dense foods can prevent weight gain and induce modest weight loss. However, even when motivated to make small changes to the diet, it is often difficult to make and maintain these changes. This so-called intention-behavior gap is likely to be reduced with Implementation Intentions (IIs). IIís are specific action plans, defining where, and when to perform a particular action. With these action plans people are more likely to turn their intended behavior into action. Effects of IIs have been found for relatively simple and singular behaviors.The present study will test the effects of implementation intentions for making changes in energy intake, a more complex behavior. The IIís are added to a computer-tailored advice delivered in web-based format. |
RCT with a pretest and 3 posttests. Post-tests took place at four weeks, three months, and six months after the intervention.
Questions adressed in this study are:
1. Can IIs contribute to making actual changes in energy intake?
2. Are II better suited to induce new healthy behaviors (e.g. increase intake of low energy products), avoid unhealthy behaviors (e.g. decrease intake of high energy products) or exchange unhealthy practices for healthy ones?
3. Which factors (e.g. cognitions, values, personality traits) distinguish people who put II into action from those who do not?
This study is part of a larger project that explores the applicability of implementation intentions in energy expenditure (physical activity) as well. That intervention study is registered elsewhere in this database.
|- Main changes (audit trail)|
|- RECORD||26-jul-2006 - 18-nov-2008|