Donna M. Woolcott

Self-Efficacy As an Intermediate Outcome Variable in the Transtheoretical Model: Validation of a Measurement Model for Applications to Dietary Fat Reduction

Abstract Banduras self-efficacy construct is one of the elements examined in the transtheoretical model. Applied to dietary fat reduction, self-efficacy is conceptualized as confidence in the ability to avoid consuming high-fat foods in three situations (positive/social, negative/affective, and difficult/ inconvenient). The validity of a 12-item situational self-efficacy scale designed to measure confidence for dietary fat reduction in a U.S. population was investigated with a random sample of 491 adult women living in the Guelph, Ontario area. Participants were recruited by telephone and completed a mailed, self-administered questionnaire. Principal components analysis revealed a three-factor structure accounting for 74% of the variance in self-efficacy. Loadings on the three factors ranged from .62 to .96. The three factors demonstrated high internal consistency (alpha) coefficients, ranging from .83 to .95. Confirmatory factor analysis demonstrated excellent model fit (comparative fit index = .96) with all parameters significant. Self-efficacy scale scores were significantly higher among subjects assigned to action and maintenance than among those assigned to precontemplation, contemplation, and preparation, providing evidence of construct validity. This scale, developed with an American population, demonstrates validity when applied to Canadian adult women.

Defining stage of change for lower-fat eating.

OBJECTIVE To test the validity of staging methodology for dietary fat reduction by examining cognitive profiles of persons classified in these groups: precontemplation, lowerfat maintenance (< or = 30% of energy as fat), and higher-fat maintenance (> 30% of energy as fat). DESIGN Cross-sectional survey of a random sample of 491 women residing in Guelph, Ontario, Canada, recruited by telephone. SETTING/SUBJECTS Mean age of subjects was 43.7 +/- 12.2 years. The majority (58%) lived with a spouse or partner and had completed high school (68%). STATISTICAL ANALYSES Multivariate analysis of variance was used to compare the pros and cons of lower-fat eating, level of self-efficacy in avoiding high-fat foods, and use of 9 processes of change to support lower-fat eating habits in women assigned to the precontemplation, higher-fat, and lower-fat maintenance stages. RESULTS When compared with subjects classified in the precontemplation stage, the 2 groups of subjects in the maintenance stage had higher ratings of the pros (49.7 +/- 9.5 vs 43.7 +/- 7.2, P < .05), lower ratings of the cons (47.2 +/- 8.2 vs 51.9 +/- 11.8, P < .05), higher self-efficacy scores, and more frequent use of processes of change than subjects classified in the precontemplation stage. No differences between women in the 2 maintenance groups were observed in self-efficacy; however, those in the lower-fat maintenance group reported lower cons than those in the higher-fat maintenance group (46.2 +/- 7.2 vs 48.2 +/- 9.1, P < .05) and more frequent use of all processes of change. CONCLUSIONS/APPLICATIONS Stage of change for dietary fat reduction is a cognitive variable that provides insights into attitudes about and motivations to consume lower-fat foods.

Evaluation of a theoretical model predicting self-efficacy toward nutrition behaviors in the elderly

Abstract This paper describes the development and testing of a theoretical model predicting self-efficacy towards nutrition behaviors in a sample of 132 non-institutionalized older adults. The model used Banduras Social Cognitive Theory as the over-riding theoretical framework. Data were collected by personal interviews using validated instruments. Multiple regression analyses revealed direct relationships between self-efficacy and the attitude that nutrition is important, flexibility towards changing nutrition practices, and perceived social support. Morale and perceptions of health status were indirectly related to self-efficacy through perceived social support. The value of the model was tested by its ability to predict the number of nutrition-related changes reported by the sample. This model provides an example of theory-driven research in nutrition education and describes the potential value of self-efficacy in instigating changes in nutrition behaviors.

Evaluation of an affective-based adult nutrition education program

Abstract Nutrition educators have had limited success using cognitive approaches to effect behavior change. This study evaluated the effectiveness of an affective-based program in changing the nutrition attitudes and behavior of a group of adults, using pre-, post-, and retention test measures of nutrition knowledge, attitudes, and dietary behavior. The sample consisted of a treatment group (n = 59) and a control group (n = 58). The treatment group participated in a five-week nutrition course offered at a public health unit. At the conclusion of the program the respondents had improved nutrition knowledge, maintained positive attitudes, and improved reported nutrition behavior. Nutrition knowledge scores rose significantly from the pretest to posttest situations for both groups. However, only the treatment group showed a rise in knowledge scores from the pretest to the retention test. No significant changes in scores occurred on the attitude scale, which measured flexibility-rigidity in nutrition attitudes. Pretest scores were very high for both treatment and control groups, suggesting a possible ceiling effect. Nutrition behavior was measured by 24-hour recalls which were scored qualitatively. The mean behavior scores rose significantly from pretest to posttest and pretest to retention test for the treatment group only.

Nutrition knowledge and misconceptions of university students: 1971 vs. 1984

Abstract The purpose of this study was to obtain an indication of changes in the level of nutrition knowledge and prevalence of misconceptions of Canadian university students over a 13-year period. We replicated a study which measured nutrition knowledge, misconceptions, and uncertainty of knowledge of young adults entering a university. Thus, we were able to directly compare the data collected in 1971 with those collected from a comparable sample in 1984. The level of nutrition knowledge was higher in 1984 than in 1971; however, the prevalence of misconceptions and the rank order of misconceptions was similar to what was observed in 1971. These findings suggest that although university students in 1984 had a slightly higher level of nutrition knowledge than their counterparts in 1971, they still held many of the same misconceptions.

Correlates of nutrition knowledge in Canadian businessmen

Abstract We studied 195 men employed in management and executive positions in the insurance industry to determine their level of nutrition knowledge and to examine the relationship of social, demographic, and personality variables to nutrition knowledge. The respondents, who ranged in age from 18 to 72 years, scored 59% on a validated 20-item multiple-choice test of nutrition knowledge. Higher nutrition knowledge, correlated with increasing age, higher education, and higher socioeconomic status. Knowledge was also related to participation in nutrition-related activities in the home and to several personality dimensions as measured by the Sixteen Personality Factor Questionnaire. Between men high and low in knowledge were several personality differences, including differences in imaginativeness, emotional sensitivity, and extraverted orientation. The study reaffirmed some established demographic factors and added new variables, including participation in nutrition-related activities and personality factors, as contributors to understanding nutrition knowledge.

Personality Correlates of Selected Elements of the Health Belief Model

Summary One hundred and ninety-five men with an average age of 38 years and employed in sedentary work [and thus statistically at increased risk for cardiovascular disease (CVD)] replied to a questionnaire assessing the degree to which they felt susceptible to CVD, their expectations regarding the severity of an attack, if they should have one, and their perception of the benefits to be derived from engaging in appropriate preventive behavior. These three elements of the Health Belief Model (HBM) were correlated with the primary source traits of the Sixteen Personality Factor Questionnaire (16 PF). A total of eight 16 PF factors correlated with one or more elements of the HBM, five of them contributors to the second-order factor of anxiety. There was a clear tendency for anxiety dimensions to correlate with perceived susceptibility and severity, but not with benefits. These findings were interpreted as having implications for both researchers and practitioners. On the one hand, such data should encourage ...

An evaluation of a theory-based demonstration worksite nutrition promotion program.

In the last decade, the workplace has gained recognition as an ideal setting in which to influence the health behaviors of working young and middle-aged adults. Needs assessments are frequently conducted to guide program development and delivery, and evaluations generally attempt to demonstrate favorable cost-benefit ratios or changes in self-reported lifestyle behaviors. There are few reports in the literature of theory-based worksite health promotion programs. The purpose of this study was to develop and evaluate a theory-based demonstration worksite nutrition program. Consequently this worksite study differs from others in two ways. First, a conceptual framework was used to select study variables and intervention strategies. Second, changes in expectancies, values, and intentions, rather than economic outcomes or changes in selfreported lifestyle behaviors, were examined.