Adaptation of the Diabetes Health Profile (DHP-1) for use with patients with Type 2 diabetes mellitus: psychometric evaluation and cross-cultural comparison.

AIMS

To adapt the Diabetes Health Profile (DHP-1) for use with English speaking patients with Type 2 diabetes mellitus and to evaluate the psychometric properties of the adapted measure in a UK and Danish sample of insulin, tablet and diet-treated patients with Type 2 diabetes.

METHODS

Following linguistic adaptation using the forward-backward translation procedure, the 32-item DHP-1 was sent to 650 and 800 consecutively selected UK and Danish patients with Type 2 diabetes. Construct validity was assessed using principal axis factoring. Factor stability was assessed across language groups using the coefficient of congruence. Reliability was evaluated using Cronbach's alpha and multi-trait analysis, including item convergent/discriminant validity. Subscale discriminant validity was assessed through known groups with one-way ANOVA and post hoc Scheffe tests for multiple comparisons.

RESULTS

Eighteen items (56.25%) were retained following initial item analysis. A three-factor solution accounting for 45.6% and 40.3% of the total explained variance was identified in the UK and Danish samples, respectively. Factors were interpreted as psychological distress (PD), barriers to activity (BA) and disinhibited eating (DE). Factor congruence between language groups ranged from 0.98 to 0.99 and Cronbach's alpha ranged between 0.70 and 0.88. Item scaling success for both language versions was 88.9%. BA scores discriminated between treatment groups in both language groups (F = 24.24, P < 0.001; F = 7.68, P < 0.001) and PD scores in the UK sample (F = 20.97, P < 0.001).

CONCLUSIONS

The DHP-18 developed for use with patients with Type 2 diabetes has been shown to have satisfactory internal reliability and validity and measurement equivalence across language groups.