Validation of a Questionnaire to Evaluate Simplicity of Diabetes Treatment (SIM-Q)
Author(s)
Kristina S. Boye, MPH, MS, RPh, PhD1, Louis Matza, PhD2, Katelyn N. Cutts, MS2, Karin Coyne, PhD2;
1Eli Lilly and Company, Indianapolis, IN, USA, 2Evidera, Outcomes Research, Bethesda, MD, USA
1Eli Lilly and Company, Indianapolis, IN, USA, 2Evidera, Outcomes Research, Bethesda, MD, USA
OBJECTIVES: The Simplicity of Diabetes Treatment Questionnaire - Status version (SIM-Q-status) was developed based on qualitative input from patients to evaluate patient perceptions of the simplicity and complexity of their current treatment for type 2 diabetes (T2D). The purpose of this study was to assess the psychometric properties of the SIM-Q-status.
METHODS: Patients living with T2D and treated with a variety of medications (oral medications, GLP-1 receptor agonists, tirzepatide, and/or insulin) were recruited from eight clinical sites across the US. They completed the SIM-Q-status along with other measures to be used in analysis of validity. Analyses focused on item performance, scale identification, reliability, and validity.
RESULTS: The sample included 250 patients (mean age = 59.7y; 54.4% female). Based on item performance and exploratory factor analysis, all 10 items were retained. Eight items characterized treatment simplicity and contributed to a single treatment simplicity scale. The other two items are global items assessing simplicity of medication and simplicity of diabetes management. The SIM-Q-status treatment simplicity scale demonstrated good internal consistency reliability (Cronbach’s α=0.90). The treatment simplicity scale and the two global items demonstrated good test-retest reliability with no significant differences between administrations 7+2 days apart among stable patients (n=37; ICCs: 0.80, 0.72, and 0.73). Construct validity was supported by moderate to strong correlations with the TRIM-D treatment burden subscale (all P values <0.0001). The SIM-Q-status demonstrated known-groups validity by differentiating among patients that reported different levels of emotional well-being and treatment burden. The SIM-Q-status may differentiate among treatments, as tirzepatide-treated patients (n=58) had significantly higher scores (indicating greater simplicity) on the global items than semaglutide-treated (n=47) patients (both p<0.05).
CONCLUSIONS: The SIM-Q-status demonstrated good reliability and validity, with a single factor structure and two global items. This questionnaire may be useful in studies assessing the simplicity and complexity of treatment for T2D.
METHODS: Patients living with T2D and treated with a variety of medications (oral medications, GLP-1 receptor agonists, tirzepatide, and/or insulin) were recruited from eight clinical sites across the US. They completed the SIM-Q-status along with other measures to be used in analysis of validity. Analyses focused on item performance, scale identification, reliability, and validity.
RESULTS: The sample included 250 patients (mean age = 59.7y; 54.4% female). Based on item performance and exploratory factor analysis, all 10 items were retained. Eight items characterized treatment simplicity and contributed to a single treatment simplicity scale. The other two items are global items assessing simplicity of medication and simplicity of diabetes management. The SIM-Q-status treatment simplicity scale demonstrated good internal consistency reliability (Cronbach’s α=0.90). The treatment simplicity scale and the two global items demonstrated good test-retest reliability with no significant differences between administrations 7+2 days apart among stable patients (n=37; ICCs: 0.80, 0.72, and 0.73). Construct validity was supported by moderate to strong correlations with the TRIM-D treatment burden subscale (all P values <0.0001). The SIM-Q-status demonstrated known-groups validity by differentiating among patients that reported different levels of emotional well-being and treatment burden. The SIM-Q-status may differentiate among treatments, as tirzepatide-treated patients (n=58) had significantly higher scores (indicating greater simplicity) on the global items than semaglutide-treated (n=47) patients (both p<0.05).
CONCLUSIONS: The SIM-Q-status demonstrated good reliability and validity, with a single factor structure and two global items. This questionnaire may be useful in studies assessing the simplicity and complexity of treatment for T2D.
Conference/Value in Health Info
2025-05, ISPOR 2025, Montréal, Quebec, CA
Value in Health, Volume 28, Issue S1
Code
PCR128
Topic
Patient-Centered Research
Topic Subcategory
Instrument Development, Validation, & Translation, Patient-reported Outcomes & Quality of Life Outcomes
Disease
SDC: Diabetes/Endocrine/Metabolic Disorders (including obesity)