An Exploratory Study of Alternative Timeframes and Descriptors for EQ-5D-5L in Obstructive Airway Diseases Using Mixed Methods.

Objectives EQ-5D-5L with its recall time of “today” may limit its ability to capture episodic symptoms and exacerbations in chronic obstructive airway diseases (OAD). We examined whether longer timeframes and changing the intensity response scales to frequency scales could improve the measurement properties of EQ-5D-5L. Methods We used a mixed method design starting with in-depth interviews with 20 patients and clinicians to elicit preferred timeframes using concept elicitation techniques and content analyses. We then administered the top four preferred variants using one- & four-weeks’ timeframes with the original intensity or an alternative frequency response scale alongside EQ-5D-5L and St George Respiratory Questionnaire (SGRQ) to OAD patients during two different visits. We compared the ceiling effects and construct validity by testing a priori hypotheses in relation to SGRQ and clinical outcomes via correlation and receiver operating characteristic (ROC) analyses, respectively. Follow-up patients were categorized into “better”, “stable”, and “worse” groups to assess reliability using intra-class correlation coefficient (ICC) or Cohen’s Kappa (k), and responsiveness using ROC analysis. Results 184 patients (mean [SD] age: 54[18]; female: 37.0%) completed baseline assessments.120 patients also completed follow-up assessments (mean [SD] interval: 2.8 [1.7] months). The ceilings were lower in the variants compared to EQ-5D-5L (p<0.001). Reliability of the variants were comparable to or higher than EQ-5D-5L. The c-statistic values derived from ROC analyses of the variants were consistently higher than EQ-5D-5L. Conclusions Use of longer timeframes with the original intensity or the frequency response scales may improve EQ-5D-5L’s psychometric properties in OAD patients. (248 words)