The stages of change for dietary fat and fruit and vegetable intake of patients at the outset of a cardiac rehabilitation program

The transtheoretical model as applied to dietary behaviour and outcomes

The transtheoretical model (TTM) is a behavioural theory that describes behaviour change as occurring in five stages, ranging from precontemplation to maintenance. The purpose of the present paper is to review and synthesise the literature published since 1999 on applications of the TTM to dietary behaviour so that the evidence for the use of assessment tools and interventions based on this model might be evaluated. Six databases were identified and searched using combinations of key words. Sixty-five original, peer-reviewed studies were identified and summarised in one of three tables using the following categories: population (n 21), intervention (n 25) and validation (n 19). Internal validity ratings were given to each intervention, and the body of intervention studies as a whole was rated. The evidence for using stage-based interventions is rated as suggestive in the areas of fruit and vegetable consumption and dietary fat reduction. Valid and reliable staging algorithms are available for fruit and vegetable consumption and dietary fat intake, and are being developed for other dietary behaviours. Few assessment tools have been developed for other TTM constructs. Given the popularity of TTM-based assessments and interventions, more research is warranted to identify valid and reliable assessment tools and effective interventions. While the evidence supports the validity of the TTM to describe populations and to form interventions, evidence of the effectiveness of TTM-based interventions is not conclusive.

Investigating fruit and vegetable consumption using the transtheoretical model

PURPOSE

Test the applicability of the transtheoretical model (TTM) to adult fruit/vegetable consumption.

DESIGN

Cross-sectional random-digit dial survey.

SETTING

Hawaii.

SUBJECTS

700 (62.6% female; age [mean +/- SD], 47 +/- 17.1 years; education [mean +/- SD], 14.6 +/- 2.8 years; 35.0% white, 31.1% Asian, 22.1% native Hawaiian/Pacific Islander, 11.8% other).

MEASURES

Stages, processes, self-efficacy, decisional balance, and self-reported fruit/vegetable consumption.

ANALYSIS

Confirmatory factor analysis tested the factor structure. Analyses of variance were used to explore stage differences in constructs.

RESULTS

Stage distribution was precontemplation (33%), contemplation (4%), preparation (37%), action (3%), and maintenance (23%). A 10-factor process model with two higher-order correlated factors (experiential and behavioral) provided the best data fit (chi2 = 1446.12; df = 366; p < .0001; comparative fit index [CFI] = .89; standardized root mean square residual [SRMR] = .05). The self-efficacy structure fit the data well (chi 2 = 81.86; df = 9; p < .0001; CFI = .94; SRMR = .04), as did the decisional balance structure (chi2 = 37.42; df = 19; p = .007; CFI = .99; SRMR = .02). Processes, self-efficacy, decisional balance, and fruit/vegetable consumption behavior differed significantly by stage, with medium effect sizes for most variables.

CONCLUSION

The variables revealed adequate fit to the theorized measurement models. TTM predictions regarding stage differences in self-efficacy, pros and cons, and fruit/vegetable consumption were confirmed; however, most experiential and behavioral processes increased in the early stages and then leveled off.

Experiences of older women increasing fruit and vegetable intake

Many studies have investigated diet in relation to disease and other aspects of health, although there is little information for health professionals on conveying practical ways for people to improve dietary intakes. There is thought to be a positive link between bone health and fruit and vegetable intake. This paper reports on the experiences of older women increasing their fruit and vegetable intake while participating in a randomized controlled trial to assess the influence of fruit and vegetables on bone health. How the women achieved increases in fruit and vegetable intake is described.

Are the stages of change socioeconomically distributed? A scoping review

OBJECTIVE

To conduct a rapid scoping review to explore the hypothesis that socioeconomic affluence is associated with a more advanced stage of change for health behaviors.

DATA SOURCE

Key-word searches of MEDline, Embase, PyschlNFO, and www.google.com were conducted.

STUDY INCLUSION AND EXCLUSION CRITERIA

Studies identified by the searches were included if they were published between 1982 and September 2003, written in English, and reported information on the distribution of the stages of change for any health behavior according to a marker of socioeconomic position (SEP).

DATA EXTRACTION

Data on the behavior studied, the sample studied, the measure of SEP used, the definitions of the stages of change used, and the distribution of the stages of change according SEP were extracted by a single reviewer.

DATA SYNTHESIS

As far as possible, data were reanalyzed by the chi-square test to determine if there was evidence that the distribution of the stages of change varied according to SEP. A formal meta-analysis was not appropriate. Results. Twenty-one studies reporting data on 30 samples and 188,850 individuals were included. Significant variations in the distribution of the stages of change were found according to SEP, in the expected direction, in 16 (53%) samples representing 171,183 (91%) individuals.

CONCLUSIONS

There is substantial published evidence that more-affluent people tend to be in more-advanced stages of change than are more-deprived people.

Comparison of Two Nutrition Education Approaches to Reduce Dietary Fat Intake and Serum Lipids Reveals Registered Dietitians Are Effective at Disseminating Information Regardless of the Educational Approach

OBJECTIVE

The purpose of this study was to compare an educational approach based on the Stages of Change Model with usual care education in reducing dietary fat intake and serum lipids in individuals with hyperlipidemia.

DESIGN

A 40-week randomized control study was conducted. Four education sessions were provided on an outpatient basis during a 1-month period with follow-up every 6 weeks.

PARTICIPANTS

The sample consisted of 141 men and women with hyperlipidemia (mean age 50+/-11 years and a mean body mass index of 30+/-6) randomly assigned to one of two education interventions.

INTERVENTION

The stages of change group was provided with tailored dietary activities based on their readiness to change to reduce dietary fat intake. Dietary information and activities for the usual care program were developed for those individuals ready to make a change in their diets.

MAIN OUTCOME MEASURES

Serum lipids, anthropometric measures, readiness to change, dietary intake, and exercise data were assessed at baseline, 4, 16, 28, and 40 weeks.

STATISTICAL ANALYSES

A repeated measures analysis of variance was used to compare differences between groups across time.

RESULTS

Total cholesterol, low-density lipoprotein cholesterol, and body weight decreased significantly at 4 weeks (P<0.05) for both groups and were sustained over time, with no differences between the groups.

CONCLUSIONS

The stages of change education approach was not more effective than the usual care education approach in decreasing dietary fat intake and serum lipids in a classroom setting.

Are current health behavioral change models helpful in guiding prevention of weight gain efforts?

Effective procedures are needed to prevent the substantial increases in adiposity that have been occurring among children and adults. Behavioral change may occur as a result of changes in variables that mediate interventions. These mediating variables have typically come from the theories or models used to understand behavior. Seven categories of theories and models are reviewed to define the concepts and to identify the motivational mechanism(s), the resources that a person needs for change, the processes by which behavioral change is likely to occur, and the procedures necessary to promote change. Although each model has something to offer obesity prevention, the early promise can be achieved only with substantial additional research in which these models are applied to diet and physical activity in regard to obesity. The most promising avenues for such research seem to be using the latest variants of the Theory of Planned Behavior and Social Ecology. Synergy may be achieved by taking the most promising concepts from each model and integrating them for use with specific populations. Biology-based steps in an eating or physical activity event are identified, and research issues are suggested to integrate behavioral and biological approaches to understanding eating and physical activity behaviors. Social marketing procedures have much to offer in terms of organizing and strategizing behavioral change programs to incorporate these theoretical ideas. More research is needed to assess the true potential for these models to contribute to our understanding of obesity-related diet and physical activity practices, and in turn, to obesity prevention.

A 2-year stage of change evaluation of dietary fat and fruit and vegetable intake behaviors of cardiac rehabilitation patients

PURPOSE

To track the 2-year movement of cardiac rehabilitation patients through the stages of change for dietary fat reduction and increasing fruit and vegetable intake.

DESIGN

A cross-sectional, longitudinal evaluation of a convenience sample of cardiac rehabilitation patients.

SETTING

Department of Pulmonary and Cardiac Rehabilitation, Moses H. Cone Memorial Hospital, Greensboro, North Carolina.

SUBJECTS

Subjects (n = 118) were predominately white, overweight, married men with a history of tobacco use.

INTERVENTION

Group nutrition education sessions for 12 weeks.

MEASURES

Stage of change assessments for dietary fat reduction and increasing fruit and vegetable intake were performed at the start (baseline), conclusion (3 months), and 2 years after cardiac rehabilitation.

RESULTS

Baseline staging demonstrated patients' efforts to reduce dietary fat intake (preparation, 10.2%; action, 35.6%; maintenance, 47.5%). The assessment at 2 years staged 87.3% of the population in the maintenance stage. In contrast, the precontemplation (30.0%), contemplation (7.6%), and preparation (49.2%) stages dominated baseline staging for modifying fruit and vegetable intake. Patients in the precontemplation and contemplation stages increased to 58.5% at 2 years.

CONCLUSIONS

Cardiac rehabilitation patients are in different stages for two food behaviors linked to the same illness. Results support the appropriateness of nutrition education that emphasizes instrumental information for affecting fat reduction behaviors. Modifying fruit and vegetable intake behaviors is more appropriately addressed with noninstrumental interventions that emphasize health benefits and barriers to change.

Patients' readiness for dietary change at the beginning of counselling: a transtheoretical model-based assessment

BACKGROUND

The purpose of this study was to explore patients' readiness for dietary change within a theoretical framework of the transtheoretical model. The patients were recently diagnosed to have type 2 diabetes or impaired glucose tolerance. We discuss the theoretical aspects of appropriate dietary counselling strategies from a standpoint of patient-specific stages of change.

METHODS

The data included 32 audiotaped diabetes counselling sessions with 16 patients conducted by two nurses. The transcribed data was analysed by using deductive content analysis.

RESULTS

The patients were at different stages of change of diabetes-affected dietary behaviour. Their stages of change varied in different dietary areas and within certain dietary habits. These stages of change could involve their overall dietary behaviour or some minor aspects of their diets.

CONCLUSIONS

Understanding patient-specific stages of change orientates health counsellors to use the most appropriate counselling strategies. The transtheoretical framework helps counsellors to perceive the total range of patients' different stages of change and their effect on the implementation of counselling. However, determining patients' stages of change through examining counselling conversations is occasionally difficult. Further qualitative research is called for.