Generic and diabetes-specific well-being in the AT.LANTUS Follow-on study: further psychometric validation of the W-BQ28 indicates its utility in research and clinical practice in Type 2 diabetes in the UK.
ABSTRACT To undertake further psychometric validation of the W-BQ28 to determine its suitability for use in adults with Type 2 diabetes in the UK using data from the AT.LANTUS follow-on study.
A total of 353 people with Type 2 diabetes participated in the AT.LANTUS Follow-on study, completing measures of well-being (W-BQ28), treatment satisfaction (DTSQ) and self-care (SCI-R). Confirmatory factor analyses was used to confirm the W-BQ28 structure and internal consistency reliability was assessed. Additional statistical tests were conducted to explore convergent, divergent and known-groups validity. Minimal important differences were calculated using distribution and anchor-based techniques.
Structure of the W-BQ28 (seven four-item subscales plus 16-item generic and 12-item diabetes-specific scales) was confirmed (comparative fit index = 0.917, root mean square error of approximation (RMSEA) = 0.057). Internal consistency reliability was satisfactory (four-item subscales: alpha = 0.73-0.90; 12/16-item scales: α = 0.84-0.90). Convergent validity was supported by expected moderate to high correlations (r(s) = 0.35-0.67) between all W-BQ28 subscales (except Energy); divergent validity was supported by expected low to moderate correlations with treatment satisfaction (r(s) = -0.03-0.52) and self-care (r(s) = 0.02-0.22). Known-groups validity was supported with statistically significant differences by sex, age and HbA(1c) for expected subscales. Minimal important differences were established (range 0.14-2.90).
The W-BQ28 is a valid and reliable measure of generic and diabetes-specific well-being in Type 2 diabetes in the UK. Confirmation of the utility of W-BQ28 (including establishment of minimal important differences) means that its use is indicated in research and clinical practice.
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ABSTRACT: Large prospective studies have demonstrated that optimum glycemic control is not routinely achieved in clinical practice. Barriers to optimal insulin therapy include hypoglycemia, weight gain, and suboptimal initiation and dose titration. This study compared two treatment algorithms for insulin glargine initiation and titration: algorithm 1 (investigator led) versus algorithm 2 (performed by study subjects). A prospective, multicenter (n = 611), multinational (n = 59), open-label, 24-week randomized trial in 4,961 (algorithm 1, n = 2,493; algorithm 2, n = 2,468) suboptimally controlled type 2 diabetic subjects. At baseline, mean diabetes duration was 12.3 +/- 7.2 years, and 72% of subjects were pretreated with insulin. At end point, there was no significant difference in the incidence of severe hypoglycemia between algorithms 1 and 2 (0.9 vs. 1.1%). There was a significant reduction in HbA(1c) from 8.9 +/- 1.3 to 7.8 +/- 1.2%, with a greater decrease (P < 0.001) with algorithm 2 (-1.22%) versus algorithm 1 (-1.08%). Fasting blood glucose decreased from 170 to 110 mg/dl, with a greater decrease (P < 0.001) with algorithm 2 (-62 mg/dl) versus algorithm 1 (-57 mg/dl). Mean basal insulin dose increased from 22.9 +/- 15.5 to 43.0 +/- 25.5 IU, with a significant difference (P < 0.003) between algorithm 2 (21.6 IU) and algorithm 1 (18.7 IU). Glargine is safe and effective in improving glycemic control in a large, diverse population with longstanding type 2 diabetes. A simple subject-administered titration algorithm conferred significantly improved glycemic control with a low incidence of severe hypoglycemia compared with physician-managed titration.Diabetes Care 07/2005; 28(6):1282-8. · 7.74 Impact Factor
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ABSTRACT: To examine psychometric properties of the Self-Care Inventory-revised (SCI-R), a self-report measure of perceived adherence to diabetes self-care recommendations, among adults with diabetes. We used three data sets of adult type 1 and type 2 diabetic patients to examine psychometric properties of the SCI-R. Principal component and factor analyses examined whether a general factor or common factors were present. Associations with measures of theoretically related concepts were examined to assess SCI-R concurrent and convergent validity. Internal reliability coefficients were calculated. Responsiveness was assessed using paired t tests, effect size, and Guyatt's statistic for type 1 patients who completed psychoeducation. Principal component and factor analyses identified a general factor but no consistent common factors. Internal consistency of the SCI-R was alpha = 0.87. Correlation with a measure of frequency of diabetes self-care behaviors was r = 0.63, providing evidence for SCI-R concurrent validity. The SCI-R correlated with diabetes-related distress (r = -0.36), self-esteem (r = 0.25), self-efficacy (r = 0.47), depression (r = -0.22), anxiety (r = -0.24), and HbA(1c) (r = -0.37), supporting construct validity. Responsiveness analyses showed SCI-R scores improved with diabetes psychoeducation with a medium effect size of 0.62 and a Guyatt's statistic of 0.85. The SCI-R is a brief, psychometrically sound measure of perceptions of adherence to recommended diabetes self-care behaviors of adults with type 1 or type 2 diabetes.Diabetes Care 07/2005; 28(6):1346-52. · 7.74 Impact Factor
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ABSTRACT: Insulin therapy has proven benefits in Type 2 diabetes patients when combination therapy has failed. However, there is some reluctance by both patients and healthcare professionals to initiate insulin therapy. This reluctance has been termed 'psychological insulin resistance'. Barriers to the initiation of insulin therapy include patients' fear of disease progression and needle anxiety; mutual concerns about hypoglycaemia and weight gain; and health professionals' use of insulin as a threat to encourage compliance with earlier therapies. It is essential that these obstacles are identified and investigated as a means of overcoming these impediments to recommended levels of glycaemic control, an initiative being pursued by the DAWN study. Where concerns are tangible, such as fear of hypoglycaemia, therapeutic solutions can be pursued. Overcoming psychological barriers relies more on innovative management techniques. Improving insulin delivery to meet these needs, coupled with enhanced healthcare services, can address psychological insulin resistance and contribute to the maintenance of good metabolic control.International Journal of Obesity 10/2002; 26 Suppl 3:S18-24. · 5.22 Impact Factor