Purpose: The Myelofibrosis Symptom Assessment Form version 4.0 (MFSAF v4.0) comprises 7 common MF symptom items (fatigue, night sweats, pruritus, abdominal discomfort, pain under the left ribs, early satiety, bone pain) and is the first patient-reported outcome (PRO) instrument designed to assess MF symptom burden. Given that information on the psychometric properties of this instrument has been limited, we sought to evaluate its measurement properties and validate its use in the phase 3 MOMENTUM trial.
Methods: Data were pooled to assess MFSAF item distribution, structural validity, reliability (test-retest and internal consistency), construct validity (convergent, divergent, and known-groups), and sensitivity to change. Other PRO measures included Patient Global Impression of Severity/Change (PGIS/PGIC), EORTC QLQ-C30, PROMIS Physical Function Short Form 10b, and ECOG performance status.
Results: Participants (N = 195) showed high completion rates (> 93%) across 24 weeks. Moderate to strong Spearman correlation coefficients among items were mostly observed at baseline (range, 0.289-0.772) and week 24 (range, 0.391-0.829), which supported combining items into a multi-item scale and total score. Internal consistency (Cronbach's α, 0.877 at baseline and 0.903 at week 24) and test-retest reliability (intraclass correlation coefficient, > 0.829) were satisfactory across selected time intervals. Reliability was also supported by McDonald's omega (ω) coefficient (> 0.875). MFSAF moderately correlated with PRO measures of similar content, differentiated between PGIS and ECOG groups (P < .001), and was able to detect change over time.
Conclusions: The MFSAF v4.0 is a valid tool to assess MF symptom burden, supporting its use in future trials in similar populations.
Keywords: Anemia; MOMENTUM; Myelofibrosis; Patient-reported outcomes; Psychometrics.
Evaluating treatments for the rare blood cancer myelofibrosis involves understanding symptom severity and the impact it has on patients’ emotions, physical activities, and quality of life. The Myelofibrosis Symptom Assessment Form Total Symptom Score version 4.0 (MFSAF TSS v4.0) is a questionnaire that asks patients to report the severity of seven symptoms (tiredness, night sweats, itching, stomach pain, pain under the left ribs, getting full quickly, bone pain) on a 0 (absent) to 10 (worst imaginable) rating scale. Currently, no tool other than the MFSAF is available to evaluate myelofibrosis symptoms. This questionnaire was used in the MOMENTUM clinical trial and the total score for each patient was used to calculate the main result of the study. MOMENTUM was the first trial to assess momelotinib, a potential treatment for myelofibrosis, specifically in patients with myelofibrosis and anemia (too few red blood cells). Because anemia is common in myelofibrosis and patients with myelofibrosis and anemia have a high medical need, it is important that questionnaires like the MFSAF TSS v4.0 measure the most relevant symptoms that impact these patients’ quality of life, so the impact of treatment on those symptoms can be measured. The objective of this study was to assess the measurement properties (statistical measures of how relevant the questionnaire is) of the MFSAF TSS v4.0 using data from the MOMENTUM trial. Overall, results showed that the MFSAF TSS v4.0 demonstrated good to excellent measurement properties and confirm its use in the MOMENTUM study was appropriate to evaluate patients’ symptoms.
© 2024. The Author(s).