Development and Validation of a Patient-Reported Outcome Measure to Assess the Impact of Steroids in the Treatment of Myeloma: The Steroid Symptom Questionnaire-Multiple Myeloma.

Objectives: Steroids routinely used in the treatment of multiple myeloma (MM) are associated with adverse effects affecting health-related quality of life (HRQoL). No assessment tool existed to measure the impact of steroids in this population. We developed and psychometrically evaluated the Steroid Symptom Questionnaire-Multiple Myeloma (SSQ-MM).

Methods: A conceptual framework for steroid-related PROs was developed through a systematic review and qualitative interviews. An existing tool was adapted and pretested with patients (n = 5), carers (n = 3), and clinicians (n = 9) for relevance and face validity. In field test 1, the draft-SSQ-MM was administered to 70 patients. Items were chosen based on item-level analysis for acceptability. In Field Test 2, the psychometric properties of the final SSQ-MM were assessed in 140 patients as part of a multicenter study. The SSQ-MM was administered alongside the EORTC QLQ-C30 and MY20, with the SSQ-MM administered again 1 week later.

Results: The SSQ-MM contains 20 items. Stability reliability was supported (ICC = 0.846), and item-total correlations ranged between 0.266 and 0.677, excluding hiccups and blood glucose, which were retained due to clinical relevance. Exploratory factor analysis supported a total score and four multi-item subscales with acceptable internal consistency (α = 0.64 to 0.82). We found evidence of convergent and divergent validity between scales measuring similar and dissimilar constructs on QLQ-C30. The SSQ-MM total score was able to differentiate between patient groups clinically known to differ.

Conclusions: The SSQ-MM provides a validated PROM for use in research and clinical settings to assess the impact of steroids and identify those who may benefit from dose reduction to improve PROs, including HRQoL.

Implications for nursing practice: Integrating assessment of steroid adverse effects using the SSQ-MM into routine nursing care can help direct timely interventions or referrals to assist patients better manage the emotional and behavioural effects of steroids. Dose optimisation may reduce steroid effects and improve HRQoL.