Psychometric properties of the Perceived Therapeutic Efficacy Scale for adhering to a cholesterol-lowering diet

Psychometric Properties of the Korean Version of the Perceived Therapeutic Efficacy Scale for Physical Activity in Adults With Type 2 Diabetes

PURPOSE

The purpose of this study is to translate the Perceived Therapeutic Efficacy Scale (PTES) into Korean and investigate its validity and reliability.

METHODS

The authors conducted a cross-sectional survey using baseline data from a randomized controlled study to psychometrically validate the PTES-Korean (PTES-K) among 108 adults with type 2 diabetes from an outpatient clinic at a university-affiliated hospital in Korea. The original PTES was forward-translated and back-translated to ensure translation equivalence of the PTES-K. Structured questionnaires were used for psychometric evaluation; exploratory and confirmatory factor analysis assessed validity, and Cronbach's alpha coefficient and intraclass correlation coefficient (ICC) were used for reliability.

RESULTS

The interitem correlation analyses revealed that 5 items were redundant; thus, the scale was reduced to 5 items. A 1-factor model explained 76.85% of the variance; confirmatory factor analysis showed that this model adequately fit the data. The ICC for test-retest reliability was .78; Cronbach's alpha was .92. The PTES-K showed significant associations with the scores of diabetes self-care activities for physical activity, quality of life, and depressive symptoms. Participants with good glycemic control and regular physical activity tended to have a higher score on the PTES-K than their counterparts, demonstrating known-groups validity.

CONCLUSIONS

The cross-cultural applicability, reliability, and validity of the PTES-K were confirmed. The PTES-K may be used in clinical settings to examine the potential role of perceived therapeutic efficacy for physical activity in enhanced glycemic control among patients with diabetes.

Psychosocial Features of Clinically Relevant Patient Subgroups With Serious Mental Illness and Comorbid Diabetes

OBJECTIVE

Care for people with serious mental illness and diabetes is complicated by clinical heterogeneity. This cross-sectional analysis of 200 individuals with comorbid serious mental illness and diabetes explored differentiation between patient subgroups that were characterized on the basis of selected dimensions within a biopsychosocial framework.

METHODS

Relationships between self-efficacy, treatment expectation, social support, and depression were first assessed via bivariate Spearman correlations among 200 individuals participating in a randomized controlled trial who had diabetes along with major depression, bipolar disorder, or schizophrenia. Next, latent profile analyses were conducted to determine underlying subgroups on the basis of these variables. The resultant groups were compared on diabetes control, function, and symptoms.

RESULTS

Two subgroups emerged. One had more severe psychiatric symptoms, low scores on other psychosocial variables, and worse diabetes control. The other had low levels of psychiatric symptoms, better scores on other variables, and better diabetes control.

CONCLUSIONS

Symptom presentation and internal and external resources appeared to be related to diabetes control for people with comorbid diabetes and serious mental illness. Care approaches need to go beyond standard education and consider biopsychosocial variables.