Norwegian SSQ-MM: preliminary support for symptom assessment in myeloma patients receiving dexamethasone

The Steroid Symptom Questionnaire — Multiple Myeloma (SSQ-MM) was developed to assess patient-reported side effects of corticosteroid treatment in multiple myeloma. This study translated and culturally adapted it into Danish and Norwegian and provided an initial evaluation of the Norwegian version’s psychometric properties.

What was assessed

Translation and adaptation followed ISPOR good practice guidelines, including forward-backward translation and cognitive debriefing interviews with patients and clinicians. Psychometric properties were evaluated in newly diagnosed Norwegian patients with multiple myeloma receiving weekly dexamethasone. Assessments covered internal consistency, correlations with EORTC QLQ-C30 constructs, differences between groups defined by ECOG performance status, and responsiveness across three time points.

Key findings

Patients and clinicians considered both translations relevant and acceptable. The Norwegian version demonstrated acceptable internal consistency for the total score (α = 0.74) and psychological subscale (α = 0.81). Correlations were generally consistent with predefined hypotheses; differences according to ECOG status supported known-groups validity.

During treatment, the total score and several steroid-related symptoms increased significantly; fewer changes were observed after treatment discontinuation. Overall symptom levels were lower than in the original Australian validation study.

Limits of the findings

The authors consider the findings preliminary evidence supporting the reliability, validity, and responsiveness of the Norwegian SSQ-MM. Studies in larger, more diverse populations with myeloma are needed to further evaluate its measurement properties.