Gap Analysis of Patient-Reported Outcome Measures for Systemic Lupus Erythematosus

OBJECTIVES: To examine validation evidence of patient-reported outcome (PRO) measures covering the most concepts in a systemic lupus erythematosus (SLE) conceptual disease model (CDM).

METHODS: PRO measures were identified from the literature, clinical trials databases, health technology assessment submissions, and regulatory label claims, and selected for conceptual analysis based on disease specificity and use across information sources. Concepts assessed by the selected PRO measures were mapped against an SLE CDM of the patient experience, which comprised 82 symptom and 41 impact concepts (13 impacts proximal to SLE and 28 distal). PRO measures covering the most concepts were assessed for gaps in psychometric properties using FDA guidance and COSMIN criteria.

RESULTS: Of 72 PRO measures identified, eight underwent conceptual analysis. The five measures covering the most CDM concepts were the Systemic Lupus Erythematosus Quality of Life (SLEQoL) (20/123), Lupus PRO (18/123), Systemic Lupus Activity Questionnaire (SLAQ) (18/123), Lupus-Specific Health-Related Quality-Of-Life (LupusQoL) (16/123), and Quality of Life in Systemic Lupus Erythematosus (L-QOL) (5/123). Symptoms were most comprehensively covered by the SLAQ (16/82). Impacts were most comprehensively covered by the SLEQoL (6/13 proximal, 9/28 distal) followed by the Lupus PRO (5/13 proximal, 8/28 distal). All measures had strong support for internal consistency, three had strong support for test-retest reliability (LupusQOL, Lupus PRO, L-QOL), four had strong support for content validity (LupusQoL, Lupus PRO, SLEQoL, L-QOL), and four had strong support for convergent validity (LupusQoL, Lupus PRO, SLAQ, L-QOL); only the L-QOL had strong evidence for known-groups validity. Evidence on responsiveness was missing for the L-QOL and limited for remaining measures. Overall, the LupusQOL had the fewest gaps.

CONCLUSIONS: All PRO measures reviewed require further psychometric evaluation. Balancing coverage with validation evidence, we suggest a combination of the SLAQ (for SLE symptoms) and Lupus PRO (for SLE impacts) for inclusion in SLE clinical trials.