Date of Submission




Diabetes is increasing in prevalence throughout the world. This increase is also of concern to upper-middle-income countries such as Thailand. Diabetes mellitus develops gradually and is often undetected in the early stages, leading to long-term damage of several organs in the body with related complications. Diabetes self-management education (DSME) has been found to improve knowledge, self-care behaviours, glycaemic control, and quality of life for Thai individuals with type 2 diabetes mellitus (T2DM). Thailand is a country in which family members have a fundamental role in assisting other family members in sickness and in health. Family-oriented interventions, therefore, have the potential to enhance health outcomes for individuals with T2DM. Randomised controlled trials conducted on family-carers of individuals with diabetes in Thailand are limited and none has investigated the potential benefit of a family-oriented DSME program, which includes the family-carer in the intervention.


The primary aim of this study was to test the effectiveness of a family-oriented, theoretically derived (based on self-efficacy) DSME for Thai individuals living with T2DM. The specific objectives of this research are to develop and deliver a family-oriented DSME for Thai individuals with T2DM and carers; to evaluate the effectiveness of a family-oriented DSME in improving diabetes knowledge, glycaemic control, self-efficacy, self-management, and quality of life among Thai individuals with T2DM; to develop and test the validity and reliability of the family-carer diabetes management self-efficacy scale (F-DMSES) that measures diabetes management self-efficacy among family-carers of Thai individuals with T2DM; and, finally, to measure and compare diabetes management self-efficacy between individuals with T2DM and their carers.


After developing a family-oriented DSME program, a single-blinded randomised controlled trial was conducted in rural Thailand to examine the effectiveness of the program. One hundred and forty Thai individuals with T2DM (and their carers) were randomly allocated to intervention and control arms. Those in the intervention group received routine care plus the family-oriented program that included education classes, group discussions, a home visit, and a telephone follow-up. Participants within the control group only received the routine usual care.

The sample size was estimated based on a known effect size (effect size = 0.58) from the primary outcome of diabetes self-management score (Mean difference = 8.35, SD = 14.28) (Wu et al., 2011). The level of significance was set at 0.05 (probability of type 1 error) and a power of 0.90 (1- probability of type 2 error), and a sample of 140 people (70 per group) was required.

The primary study outcome was diabetes self-management evaluated by the Summary of Diabetes Self-Care Activities measure. The secondary outcomes were diabetes knowledge evaluated by the Diabetes Knowledge Questionnaire, diabetes self-efficacy (efficacy expectation and outcome expectation) evaluated by the Diabetes Management Self-Efficacy Scale and the Perceived Therapeutic Efficacy Scale, quality of life evaluated by the 12-item Short-Form Health Survey, and glycaemic control as shown by HbA1C levels.

Outcome assessments were made overtime (baseline, week 5 and week 13 following intervention) and were evaluated using generalised estimating equations multivariable analyses. The family-carer diabetes management self-efficacy scale (F-DMSES) was developed using forward and backward translations from and to English and Thai languages and its construct and content validity, together with the internal consistency, were tested.


One hundred and forty participants were actually recruited and randomized to the intervention but 134 individuals have completed the three time points in data collection. Intention to-treat analyses were conducted in this study.

Except for age, no between-group significant differences were found in all other baseline characteristics. Diabetes self-efficacy, self-management, and quality of life improved in the intervention group but no improvement was observed in the controls. In the risk-adjusted multivariable models, compared to the controls, participants in the intervention group had significantly better self-efficacy, self-management, outcome expectations, and diabetes knowledge (p < 0.001 for all outcomes). Participation in the intervention increased the diabetes self-management score by 14.3 points (β = 14.3, (95% CI 10.7 – 17.9), p < 0.001). Self-management improved in individuals with lower BMIs and in females. No between-group differences were observed in quality of life or glycaemic control. The F-DMSES retained 14 items within 4 factors (general diet and blood glucose monitoring, medications and complications, diet in differing situations, and weight control and physical activities), and explained 72.2% of the total variance in the overarching construct. Internal consistency was high (α = 0.89). The F-DMSES was also able to measure change over time following the intervention, with an effect size of 0.9. Diabetes knowledge and management self-efficacy in family-carers improved over time. These aspects were also improved in individuals with T2DM when compared to their carers.


The family-oriented DSME program improved self-efficacy, self-management and quality of life, which in turn could decrease HbA1c levels. The F-DMSES is a valid and reliable self-administered instrument that measures the diabetes management self-efficacy of family-carers of individuals with T2DM, which can be used in clinical and research situations. Better carer diabetes knowledge improved the self-management of individuals with T2DM and greater family-carer diabetes management self-efficacy increased the diabetes management self-efficacy of individuals with T2DM. Family-carers can play an important role in supporting individuals with T2DM living in Thailand and should be formally included within educational programs. Family-carers also have the potential to provide compensatory care when required.


School of Nursing, Midwifery & Paramedicine

Document Type


Access Rights

Open Access


339 pages

Degree Name

Doctor of Philosophy (PhD)


Faculty of Health Sciences