Measures
At Time 1, one-week before the intervention, participants completed a demographic questionnaire at arrival, then via a face-to-face interview by a trained health care provider completed an integrated questionnaire. Bodyweight and height were measured, and fasting blood lipids were assessed (Table 2). Time 2 (follow-up) measurements were performed eight weeks post-intervention during which time the integrated questionnaire measures were completed, weight and height measurements repeated, and lipid profile determined. While HbA1c would have been a desirable measurement for this study, we were unable to measure HbA1c since the measurements were performed eight weeks after the intervention. HbA1c is measurable after three consecutive months. Of the pre-intervention individuals, 107 (control, n =54; intervention, n =53) participated in all sessions and completed second measurements at week-8 (Figure 1).
The questionnaires were constructed broadly according to guidelines and examples outlined in previous research (Ajzen, 1991, Sniehotta, 2009, Schwarzer, 2008), with some negatively-worded items to reduce response bias. (see Table 3). The first draft questionnaires were translated from English into Persian under the supervision of an expert panel (11 Professors of nutrition, psychology, and health promotion) familiar with both Persian and English. The content validity of questionnaires was evaluated by a content validity index (CVI) and content validity ratio (CVR) and satisfactory scores (>0.82 and >0.75) for all measures. The questionnaires were then completed by five individuals with T2D to assess wording and their comprehension of items. The integrated questionnaires are available as supplementary (Supplementary File 2-4).