Susan R. Rossi

Stages of change for reducing dietary fat to 30% of energy or less

OBJECTIVE To develop an algorithm that defines a persons stage of change for fat intake < or = 30% of energy. The Stages of Change Model describes when and how people change problem behaviors; change is defined as a dynamic variable with five discrete stages. DESIGN A stage of change algorithm for determining dietary fat intake < or = 30% of energy was developed using one sample and was validated using a second sample. SUBJECTS Sample 1 was a random sample of 614 adults who responded to mailed questionnaires. Sample 2 was a convenience sample of 130 faculty, staff, and graduate students. STATISTICS Subjects in sample 1 were initially classified in a stage of change using an algorithm based on their behavior related to avoiding high-fat foods. Dietary markers were selected for a Behavioral algorithm using logistic regression analyses. Sensitivity, specificity, and predictive value of the Behavioral algorithm were determined, then compared between samples using the Z test. RESULTS The following dietary markers predicted intake < or = 30% of fat (chi 2 = 131; P < .0001): low-fat cheese, breads without added fat, chicken without skin, low-calorie salad dressing, and vegetables for snacks. The specificity of the Behavioral algorithm was validated; the algorithm classified subjects consuming > 30% of energy from fat with 93% specificity in sample 1 and 87% in sample 2 (Z = 1.36; P > .05). Predictive value was also validated; 64% and 58% of subjects meeting the behavioral criteria had fat intakes < or = 30% of energy (Z = 1.1; P > .05). The algorithm was not sensitive, however; most subjects with fat intakes < or = 30% of energy from fat failed to meet the behavioral criteria. The sensitivity differed between samples 1 and 2 (44% and 27%, respectively; Z = 3.84; P < .0001). APPLICATIONS The Behavioral algorithm determines stage of change for fat reduction to < or = 30% of energy in populations with high fat intakes. The algorithm could be used in dietary counseling to tailor interventions to a patients stage of change.

Diabetes Self-Management: Self-reported recommendations and patterns in a large population

OBJECTIVE Diabetes self-management is the cornerstone of overall diabetes management. Yet many questions concerning self-management remain unanswered. The current study was designed to examine several questions about diabetes self-management: 1) What do individuals report being told to do? 2) What are their self-reported levels and patterns of self-care? 3) Are there differences on self-reported self-management recommendations and levels across various subgroups? RESEARCH DESIGN AND METHODS Mailed surveys were returned by 2,056 individuals (73.4% response rate). Of the total, 13.8% had IDDM and the remainder had NIDDM, with 65% of the NIDDM group using insulin. RESULTS The levels and patterns of self-management were consistent with those found in previous studies, i.e., individuals most regularly followed their prescribed medication regimen and least regularly followed recommendations for lifestyle changes of diet and exercise. There were significant differences on reported self-management recommendations across different subgroups. Comparisons on level of self-management across diabetes type revealed significant differences for diet and glucose testing. Differences were also found on self-management levels for a number of individual characteristics, including age, working status, and type of insurance, along with knowledge of the Diabetes Control and Complications Trial findings. CONCLUSIONS These findings provide important information on perceived self-management recommendations and the specific self-management levels and patterns in individuals with diabetes. The current findings may help health professionals better understand the levels and correlates of diabetes self-management and direct future research.

Multiple risk expert systems interventions: impact of simultaneous stage-matched expert system interventions for smoking, high-fat diet, and sun exposure in a population of parents.

Three stage-based expert system interventions for smoking, high-fat diet, and unsafe sun exposure were evaluated in a sample of 2,460 parents of teenagers. Eighty-four percent of the eligible parents were enrolled in a 2-arm randomized control trial, with the treatment group receiving individualized feedback reports for each of their relevant behaviors at 0, 6, and 12 months as well as a multiple behavior manual. At 24 months, the expert system outperformed the comparison condition across all 3 risk behaviors, resulting in 22% of the participants in action or maintenance for smoking (vs. 16% for the comparison condition), 34% for diet (vs. 26%), and 30% for sun exposure (vs. 22%). Proactive, home-based, and stage-matched expert systems can produce significant multiple behavior changes in at-risk populations where the majority of participants are not prepared to change.

Stages of Change for Reducing Dietary Fat Intake over 18 Months

OBJECTIVE To describe the stages of change that take place over 18 months, using the criterion of fat intake < or = 30% of total energy to define effective action and to investigate the effect of a single dietary feedback report on dietary fat reduction. DESIGN Subjects were randomly assigned to experimental or control conditions and assessed at 0, 6, 12, and 18 months for fat intake and stage of change. Subjects in the experiment group received 1 feedback report at baseline; all subjects received a report at 12 months. SUBJECTS Potential subjects (n = 614) were recruited by mail from a random sample of nonsmoking adults (32% response rate). Subjects were excluded if consuming < or = 30% of energy from fat or if pregnant or lactating (n = 145). Although 83% of subjects (n = 389) completed the 18-month study, only 296 provided complete data for all time points. The study was restricted to these 296. INTERVENTION Dietary feedback reports plus brief educational materials were provided following the experiment design. ANALYSES Repeated measures analysis of variance with fat intake (percent of energy from fat) as the dependent variable and baseline stage and condition as independent variables. In addition, t tests were used to compare groups at specific time points. RESULTS There was a main effect for time (F3,286 = 39, P < .0001) and baseline stage (F3,286 = 24, P < .0001), but no effect of feedback. There was a time-by-feedback interaction (F4,286 = 4.7, P < .01). There was a short-term effect of feedback over 6 months (t = 3.8, P < .001), but this effect was not significant at other time points. About 9% to 12% of subjects in the precontemplation or contemplation stages, 24% of subjects in the preparation stage, and 40% of unclassified subjects at baseline progressed to the action stage by 18 months. Between 12 and 18 months, subjects progressing at least 1 stage reduced their fat intake to a greater extent than subjects who failed to progress (t = 5.1, P < .0001). IMPLICATIONS Interventions targeted to stage of change have the potential for accelerating the rate of change for dietary fat reduction, but reaching the goal of fat intake < or = 30% of total energy may require more intensive interventions than a single dietary feedback report.

Transtheoretical Individualized Multimedia Expert Systems Targeting Adolescents' Health Behaviors

The transtheoretical model has advanced research and practice for many health behavior changes among adults, but few applications have been developed and applied among adolescents. This paper will describe an innovative and promising computer-based technology for standardized assessment and individualized theory-based intervention delivery called expert systems. Two different studies utilizing multimedia expert systems technology for assessing and intervening with adolescents targeting several health behaviors will be described. One study includes high school students and targets smoking cessation or prevention, sun protection, and dietary fat reduction. The other study includes urban adolescent female clients recruited in family planning clinics and targets condom adoption and either smoking cessation or prevention. The advantages and disadvantages of expert systems technology are reviewed. Multimedia expert system technology has the potential to enhance health promotion and adherence by integrating the strongest components from both clinical and public health models of intervention.

A Processes of Change Model for Weight Control for Participants in Community-Based Weight Loss Programs

The processes of change model has been successful in predicting behavior change across a wide range of both addictive and nonaddictive problem behaviors. This study was designed to examine the application of the processes of change model to weight control. Study participants included 285 women and men enrolled in three community-based weight loss programs. Results based on structural equation analyses showed that the processes of change model fit the data better than several plausible alternative models. In addition, structural analyses revealed the existence of two general (higher order) processes of change for weight control, the experiential and behavioral processes. These results are similar to those previously reported for eight other problem behaviors. Limitations of the current work and future directions for this line of research are discussed.

Validation of decisional balance and situational temptations measures for dietary fat reduction in a large school-based population of adolescents.

Brief, validated, and reliable theory-based measures specifically designed for use in large survey research with adolescent populations are needed to assess attitudes and behaviors about dietary fat consumption. This study validated two transtheoretical model (TTM)-based instruments in 2639 ninth graders from 12 Rhode Island high schools. The Decisional Balance Questionnaire for Adolescent Dietary Fat Reduction (DBQA) measures the importance adolescents assign to the pros and cons of reducing dietary fat consumption, while the Situational Temptations Questionnaire for Adolescents (STQA) measures temptations to eat high-fat foods as both a global construct and across three categories of challenging situations. Four competing models were compared for each instrument. An eight-item, correlated two-factor Pros and Cons model was validated for the decisional balance measure and a nine-item, three-factor hierarchical model was validated for situational temptations. The theoretically predicted relationships between stage of change and the pros and cons, as well as stage and situational temptations were supported. These results demonstrate that both measures have sound psychometric properties and are externally valid.

Stages of change and the intake of dietary fat in African-American women: improving stage assignment using the Eating Styles Questionnaire.

OBJECTIVE To develop an algorithm for determining the stage of change for dietary fat intake in African-American women. DESIGN We examined the relationships between stage of change, dietary fat intake, and associated eating behaviors and developed an assessment tool for placing subjects in their appropriate stage of change. SUBJECTS Working class and middle-income African-American women in Nashville, Tenn; 174 in study 1 and 208 in study 2. STATISTICAL ANALYSES Fat and fiber intake by stage of change was examined using multivariate analysis of variance. Hierarchical cluster analysis was performed using Wards method. RESULTS A significant difference in fat intake was noted between women trying to change their intake and those not trying to change in study 1 (P < .001) and study 2 (P < .03). Of those trying to change, only 34% (study 1) and 9% (study 2) of subjects reported fat intakes below the Healthy People 2000 goal of 30% of energy from fat. In study 1, cluster analysis identified 14 groups of foods that significantly separated subjects into not trying, noncompliant, and compliant categories. Compliant subjects ate out less; ate fewer snack foods and less chicken, meat, and fat; and ate more fruits, vegetables, breakfast foods, and low-fat products. These results led to development of the Eating Styles Questionnaire (study 2), which facilitated more appropriate placement of the noncompliant group in stages of change for dietary fat intake. APPLICATIONS/CONCLUSIONS These data support the stage construct of the Transtheoretical Model for dietary fat reduction in African-American women. Moreover, the Eating Styles Questionnaire (ESQ) can improve determination of stage of change for this group of women. The ESQ can be used to diagnose the eating styles that contribute to a high-fat intake and help in the design of interventions to lower fat intakes.

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.

Dietary factors and cancers of breast, endometrium, and ovary: Strategies for modifying fat intake in African American women

Modification of dietary fat and fiber could help prevent cancers of the breast, endometrium, and ovary that are prevalent in African-American women. Dietary intervention programs aimed at reducing fat intake have had mixed results in this population. The transtheoretic model is proposed for achieving dietary change. Strategies for changing health behaviors in African-American women include heightening sensitivity to cultural values among health educators and the use of multiple strategies to reinforce messages. To stimulate healthier eating, it is important to incorporate the distinct habitual eating patterns into innovative intervention methods, using effective behavioral change methods.