Transtheoretical Model: Potential Usefulness With Overweight Rural Mexican American Women

The effect of TTM-based nutrition education on decisional balance, self-efficacy and processes of change for fat intake

Purpose

The purpose of this study is to determine how transtheoretical model (TTM) constructions change through nutrition education for fat intake modification among overweight and obese women living in Shazand city, Iran.

Design/methodology/approach

A semi-experimental design with intervention and control groups (50 women in each group) was performed. TTM constructions for dietary fat intake were measured through a questionnaire in four phases: before the intervention, immediately, one month and six months after the intervention. Participants in two groups were classified into inactive and active subgroups, based on their determined stage of change. Then in the intervention group, each subgroup received a separate education program of five or eight sessions for the active and inactive subgroups, respectively.

Findings

The intervention resulted in significant progress in participants' stage of change compared to the control group (p = 0.002). Also, it resulted in an increase in the self-efficacy and decisional balance scores in both of the intervention subgroups, with these effects being more pronounced in the inactive subgroup, and these significant differences, compared to the control group, remained in the third and fourth phases. The intervention also positively impacted the behavioral processes, but this effect was not so long-lasting and decreased after six months.

Originality/value

The results indicated the intervention effectiveness and the necessity of planning educational interventions to change fat consumption behavior. This study provides further insight into effective and sustainable nutrition education strategies based on behavioral change stages rather than traditional approaches. These methods should be used to design group interventions to change individuals' health behavior in future works.

The effect of a multi-disciplinary obesity intervention compared to usual practice in those ready to make lifestyle changes: design and rationale of Whanau Pakari

BACKGROUND

Child obesity internationally has been identified as one of the major threats to future population health. Indigenous people and those from lower socio-economic backgrounds are over-represented in obesity statistics. There is a need for evidence of effect of interventions for child obesity with long-term follow-up. Whether engaging with those that are more motivated to make lifestyle changes is a useful strategy has not been fully explored. We hypothesise that in obese/overweight children, assessed as psychologically "ready for change", delivery of a 12-month multi-disciplinary intervention programme results in a significant reduction in body mass index standard deviation score.

METHODS/DESIGN

Whanau Pakari is an unblinded randomised controlled clinical trial comparing a 12 month intervention programme with standard practice, with 6 monthly assessments for 2 years, conducted in Taranaki, New Zealand (a region where 15.8 % of the population are indigenous). It specifically targets indigenous people and those in more deprived households. Obese/overweight children and adolescents aged 5-16 years are eligible. Exclusion criteria are medical/psychological conditions leading to inability to undertake physical activity/participate in group sessions; those not "ready" to make lifestyle changes; and those without a committed family member. Assessments of health parameters, dietary history, physical activity and overall health-related quality of life/psychological functioning are completed in the participant's home. Fasting blood tests are obtained at baseline, 12 and 24 months. The primary outcome is body mass index standard deviation score. Secondary outcomes include quality of life, dietary behaviour and physical activity, cardiovascular and metabolic profile (blood pressure, resting heart rate, waist circumference), glycaemic control (fasting glucose and glycated Haemoglobin), fasting insulin, and lipids. A general linear mixed model will be used to assess change from baseline using the 6, 12, 18 and 24 month measures, adjusting for age, gender, socioeconomic status and ethnicity, and whether at the contemplative or preparation/action stages of readiness for change.

DISCUSSION

This trial will inform the development of management programmes for obese children and adolescents that are appropriate for indigenous populations. It will investigate whether those at the preparation/action stage of "readiness" to make lifestyle changes are more successful in making changes than those who are contemplative.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR):12611000862943. (Date registered 15/08/2011).