Development of the Multiple Myeloma Symptom and Impact Questionnaire: A New Patient-Reported Outcome Instrument to Assess Symptom and Impacts in Patients With Multiple Myeloma.

<bold>Objectives: </bold>This study aimed to develop and assess the content validity of a patient-reported outcomes (PROs) instrument to measure symptoms and impacts experienced by patients with active multiple myeloma (MM).<bold>Methods: </bold>The PRO instrument was developed using an iterative, mixed-methods approach. The list of concepts was generated based on a review of existing evidence (qualitative studies and literature) and post hoc psychometric evaluations of 2 PRO instruments in 3 clinical trials. A total of 30 adult patients with MM from the United States participated in hybrid concept elicitation/cognitive debriefing interviews to validate the content validity of the newly developed PRO instrument. Translatability assessment was completed in 8 languages.<bold>Results: </bold>The item generation process resulted in 17 symptom and 9 impact concepts for evaluation. The concept elicitation interviews and analysis were based on the first 25 participants; evidence of saturation was observed. The cognitive debriefing interviews and analysis were based on the last 23 participants across 4 waves of interviews. On the basis patient feedback, 10 items were removed, and 1 item was added to the PRO instrument. The translatability assessment resulted in 1 minor revision. The multiple myeloma symptom and impact questionnaire (MySIm-Q) includes 11 symptom and 6 impact concepts, organized within 8 hypothesized subdomains, with each concept measured using a 5-point verbal rating scale and a 7-day recall period.<bold>Conclusions: </bold>The MySIm-Q instrument was developed using rigorous and mixed methodology and with direct input from patients who received a diagnosis of MM. The MySIm-Q has good content validity and is culturally relevant for use in global clinical trials. [ABSTRACT FROM AUTHOR]