Validation of a Questionnaire for Assessing the Emotional Impact of Treatment for Type 2 Diabetes

Louis S Matza,1 Katelyn N Cutts,1 Karin S Coyne,1 Kristina S Boye2 1PPD Evidera Patient-Centered Research, Thermo Fisher Scientific, Waltham, MA, USA; 2Global Medical Affairs, Eli Lilly and Company, Indianapolis, IN, USACorrespondence: Louis S Matza, PPD Evidera Patient-Centered Research, Thermo Fisher Scientific, 168 3rd Avenue, Waltham, MA, 02451, USA, Tel +1 301-664-7263, Email [email protected]: Emotional reactions to treatment could affect treatment adherence and treatment outcomes, and it is therefore important to assess the emotional impact of treatment and consider this impact in clinical decision-making. The Emotional Impact of Diabetes Treatment Questionnaire – Status version (EIDTQ-Status) was developed based on qualitative research with patients as the first patient-reported outcome measure to assess both the positive and negative emotional impacts of type 2 diabetes (T2D) and its treatment. This study assessed the psychometric properties of the EIDTQ-Status.Methods: Participants with T2D treated with a range of medications were recruited from eight clinical sites in the United States. Analysis of the EIDTQ-Status focused on item performance, subscale identification (including exploratory factor analysis), development of a scoring algorithm, test-retest reliability (intraclass correlation coefficients in a third of the participants who were randomized to attend a second visit), internal consistency reliability (Cronbach’s alpha), and construct validity (via comparisons to previously validated generic and diabetes-specific instruments).Results: The sample included 250 participants (mean age = 59.7 years old; 54.4% female). Based on item performance and exploratory factor analysis, 14 items were retained and grouped into three subscales: (1) positive emotions, (2) negative emotions, and (3) sense of control over diabetes, eating, and weight, as well as a total score. The EIDTQ-Status demonstrated good internal consistency reliability (Cronbach’s alphas of the three subscales and total score: 0.92, 0.88, 0.85, 0.77). Test-retest reliability was acceptable with no significant differences between administrations 7+2 days apart among stable participants (n=37; intraclass correlation coefficients: 0.85, 0.67, 0.62, and 0.88). Construct validity was supported via significant correlations with validated instruments (P< 0.0001). The EIDTQ-Status distinguished among participants who differed in reports of emotional well-being. Exploratory analysis suggests the EIDTQ-Status may differentiate between treatments. Compared with injectable semaglutide (n=47), tirzepatide-treated participants (n=58) reported a significantly greater sense of control over diabetes, eating, and weight (P=0.025).Conclusion: The EIDTQ-Status had strong factor structure with three subscales and a total score that demonstrated good reliability and validity. This questionnaire may be useful in clinical trials and observational research assessing the emotional impact of treatment for T2D.Keywords: Emotional Impact of Diabetes Treatment Questionnaire - Status version, EIDTQ-Status, type 2 diabetes, psychometric validation, patient-reported outcomes