OBJECTIVES: To determine whether the electronic MP SAP-c v3 demonstrates reliability, validity, and sensitivity to change in menstrual blood loss (MBL) when assessing HMB.

METHODS: Data collected during the ASTEROID 1 (N=623) UF phase 2 study using MP SAP-c v3, a daily bleeding diary (DBD), the standard alkaline hematin (AH) method, and several other reference patient-reported outcome instruments were analysed to assess psychometric and measurement properties of the MP SAP-c v3. Scores aggregated over 28 days (monthly) and during bleeding episodes at randomization (RND) and end of treatment (EoT) after 12 weeks were analysed. Data from ASTEROID 2 (N=228) were used to confirm findings, as appropriate.

RESULTS: ASTEROID 1 data analysis showed that response distributions of MP SAP-c v3 appropriately reflected periodic MBL and treatment-related changes, with all response options utilized. Test-retest reliability of monthly aggregate scores in stable patients was excellent (Intraclass Correlation Coefficients >0.86). Correlations of monthly and bleeding episode scores with the AH method were strong at RND (r_s=0.72/0.71, respectively) and EoT (r_s=0.97/0.93, respectively), supporting criterion validity of MP SAP-c v3. Spearman rank correlations of MP SAP-c v3 monthly and bleeding episode sum scores with the DBD were strong at RND (r_s=0.56/0.51), following commonly accepted conventions, but stronger at EoT (r_s=0.89/0.80, respectively), and generally weak-to-moderate with scores assessing symptoms beyond bleeding or health-related quality of life, supporting the convergent and divergent validity of MP SAP-c v3. There were large, significant differences in MP SAP-c v3 (p<0.001) across severity groups determined by the AH method and overall patient global impression of severity. Sensitivity of MP SAP-c v3 to change in MBL was also observed. Psychometric analyses using ASTEROID 2 data largely confirmed findings from ASTEROID 1.

CONCLUSIONS: The analysis indicates that the MP SAP-c v3 is valid, reliable and sensitive to change in MBL when assessing HMB.