Cindy L. Hanson

The accuracy of self-reports of physical activity.

This investigation determined the accuracy of self-reports of physical activity compared to observations obtained surreptitiously. Subjects were 44 adults engaged in 1 h of their preferred physical activity while actual activity levels were surreptitiously obtained and compared to immediate self-reported estimates of physical activity. Results indicated that subjects were moderately accurate in recalling their physical activity levels (R = 0.62) but underestimated sedentary activities and overestimated aerobic activities by over 300%. Males overestimated their activity relative to females, and obese subjects underestimated their activity levels compared to normal-weight subjects. Finally, a number of two-way interactions that moderated the accuracy of those subjects engaging in high chronic levels of physical activity were observed.

Effects of obesity, social interactions, and physical environment on physical activity in preschoolers.

Examined demographic, environmental, and parent-child interactional correlates of physical activity in a group of 222 preschoolers. Activity levels were assessed with a system that quantified directly observed physical activity in the natural environment. Using regression-modeling procedures, results revealed a significant relationship between (a) childs relative weight, parental weight status, and percentage of time spent outdoors (environment) and (b) childrens activity levels. Parental obesity was associated with lower levels of physical activity in children, childhood relative weight was associated with slightly higher levels of physical activity, and more outdoor activity was associated with higher activity levels. Parental participation in childrens activities also significantly interacted with levels of parental obesity in predicting activity levels. Those children with a 50% risk for obesity (as defined by both, one, or neither parent being overweight) had small changes in activity across levels of parent-child interaction, whereas those at higher risk for obesity responded with increased activity as parent-child interactions increased. Results are discussed, and the implications of these findings for future intervention efforts are examined.

Model of Associations Between Psychosocial Variables and Health-Outcome Measures of Adolescents with IDDM

The purpose of this study was to develop a model that describes the contributions of key psychosocial variables to the health outcome of adolescents with insulin-dependent diabetes mellitus (IDDM). Subjects were 93 adolescents with IDDM and their parents. Health-outcome measures included adherence and metabolic control (HbA1c). Psychosocial variables included adolescent age, chronic life stress, social competence, family relations, and family knowledge about IDDM. Multiple regression analyses showed that adherence (P < .029) and stress (P < .052) were directly related to metabolic control and that knowledge about IDDM (P < .029), family relations (P < .099), and adolescent age (P < .086) had direct effects on adherence. Combined, the independent variables accounted for 14.5% of the variance in predicting HbA1c and 18.5% of the variance in predicting adherence. In general, these findings are consistent with extant theory. The direct link between stress and metabolic control, however, contrasts with the current view that psychosocial variables affect metabolic control indirectly through their influence on adherence behavior. The methodological limitations of the findings are noted, directions for future research are suggested, and the implications for clinical interventions are described.

Coping Styles in Youths with Insulin-Dependent Diabetes Mellitus.

The relationships between two coping styles (i.e., use of personal and interpersonal resources; ventilation and avoidance) and two health outcomes (i.e., adherence and metabolic control) were evaluated in 135 youths with insulin-dependent diabetes mellitus (IDDM). Individual characteristics (i.e., age, duration of illness) and contextual variables (i.e., stress, family relations) were used to predict coping styles. Poor adherence to treatment, older adolescent age, and long duration of IDDM were correlated with ventilation and avoidance coping. Youths with short duration of IDDM were more likely to cope through the use of personal and interpersonal resources, although this strategy was not associated with health outcomes. A multiple regression analysis indicated that high ventilation and avoidance coping was predicted by high stress, low family cohesion, and older adolescent age. In addition, the interaction between family adaptability and duration of IDDM significantly predicted ventilation and avoidance coping.

Empirical Validation for a Family-Centered Model of Care

OBJECTIVE To examine whether family relations and family-life stress predict adherence behaviors and metabolic control in youths by testing a theoretically- and empirically-based model. RESEARCH DESIGN AND METHODS HbA1c levels of 157 youths 12–20 years of age with insulin-dependent diabetes mellitus (IDDM) were evaluated, along with treatment adherence and psychosocial family data based on interviews and self-reports. A family-centered model for IDDM care was analyzed with the EQS structural modeling statistical program. An additional exploratory model including HbA1c levels 6 months earlier was also tested. RESULTS Positive family relations (high family cohesion and low family conflict), especially during the first years of illness, indirectly related to good metabolic control through positive adherence behaviors. High levels of family-life stress related to worse metabolic control directly, and also indirectly via poor family relations, which in turn related to poor adherence to treatment. Longer illness duration related indirectly to metabolic control via adherence to treatment. Longer illness duration also related to maternal perceptions of higher family-life stress. Older youths perceived more family-life stress as well. The older age of the youths related indirectly to poor metabolic control through its association with poor adherence behaviors and less cohesive and more conflictual family relations. Results were consistent when earlier levels of metabolic control were included in the model, except that the direct relationship between family-life stress and metabolic control became nonsignificant. CONCLUSIONS The findings suggest that a family-centered approach to diabetes care that facilitates positive family functioning and leads to lower levels of family-life stress may be useful in promoting optimal health outcomes.

Relationship between psychosocial functioning and body fat in preschool children: A longitudinal investigation.

This study examined whether preschool children differed on measures of psychosocial functioning both cross-sectionally and longitudinally. One hundred and thirty-two children who varied in levels of body fat participated in the study along with their natural parents. Results indicated that the children did not differ in levels of self-esteem and family functioning as a function of their body fat. Prospectively, physical self-esteem weakly (but significantly) correlated with body fat at 1 and 2 years, and fathers perception of family functioning predicted body fat at 1 year only. Results suggested that childhood obesity may not develop as a result of psychosocial factors.

A prospective study of the reliability and convergent validity of three physical activity measures in a field research trial

This investigation sought to determine the test-retest reliability and convergent validity of three commonly used physical activity measures. The Stanford Physical Activity Recall, the Caltrac Activity Monitor, and a daily physical activity log were administered to 45 subjects over a 3-week period. The results indicated high levels of test-retest reliability for the Stanford and the daily log; low test-retest reliability was obtained for the Caltrac. Convergent validity was also high between the Stanford and daily log but was low for both of these measures with the Caltrac. These results suggest that the Stanford Physical Activity Recall may be the self-report measure of choice for large studies due to its high reliability and convergent validity with a more time-consuming daily log, as well as its cost- and time-efficiency. Based on the results, it is recommended that the Caltrac activity sensors not be used for field studies of physical activity until the logistical problems of their use in clinical trials are solved.

Physical activity, body composition, and blood pressure: a multimethod approach.

The purpose of the current investigation was to evaluate, using multiple measures of physical activity, the relationships among physical activity, body composition, resting heart rate, and blood pressure in an adult population. Subjects were 221 male (135 normal weight, 86 overweight) and 221 female (156 normal weight, 65 overweight) subjects participating in a longitudinal study of cardiovascular risk factors in families. All subjects were administered three physical activity questionnaires. Principal components analyses were conducted to reduce measures into empirically derived subscales; this analysis revealed five stable factors in men and four in women. Results indicated that aerobic/leisure time significantly correlated to body composition and resting heart rate in both men and women. Additionally, aerobic/leisure time activity was related to blood pressure in women, and moderate activity was related positively to blood pressure in men. No other form of activity (e.g., light activity, anaerobic activity) was related to either adiposity or blood pressure. The implications of these results are discussed, and future research directions are highlighted.