A test of the reliability and validity of a diabetes specific quality of life scale in a Nigerian hospital.

Abstract

The purpose of this study was to test the reliability of the Well-being and Diabetes Treatment Satisfaction Questionnaires among clinic patients with type 2 diabetes as well as determine the clinical correlates of these measures. A cross-sectional survey was conducted using the Well-being Questionnaire and the Diabetes Treatment Satisfaction Questionnaire. Other demographic and clinical indices of age, sex, body mass index, disease duration and blood glucose levels were also recorded. 83 responses were analysed. Subjects were aged between 25 and 75 years, mean 55.5+/-11.1 years. 50.6% were males while 49.4% were females. Mean diabetes duration was 4.9+/-6.5 years. 67 (80.7%) were receiving oral agents and dietary modification while 16 (19.3%) were on insulin therapy. The internal consistency for responses to the well-being subscales and treatment satisfaction scale produced satisfactory alpha coefficients ranging from 0.73 to 0.88 and 0.74 respectively. Inter-item correlations were ranged between 0.19 and 0.45 for depression subscale; 0.22-0.78 for anxiety subscale; 0.33-0.58 for energy subscale; 0.33-0.79 for positive well-being subscale; and -0.22 to 0.79 for the treatment satisfaction scale. Item-total correlations ranged between 0.39 and 0.87 across the two scales: well-being (0.59-0.87) and treatment satisfaction (0.39-0.78). Mean scale scores were similar in both insulin and oral hypoglycaemic drug treated patients. Positive well-being was higher in males 13.4+/-4.1 vs. 11.5+/-4.3 in females p = 0.04. None of the well-being subscale scores, or treatment satisfaction correlated with age, disease duration, body mass index or glycaemic control. The well-being and treatment satisfaction scales are reliable instruments for the measurement of diabetes specific quality of life and treatment satisfaction in Nigerians although they were originally designed and developed among a UK population. It is hoped that our data would provide the basis for future comparisons and improving diabetes care.