Haddox D, Mackin DM, Griffin TZ, et al. Psychometric properties and validity of a Mobile Patient Health Questionnaire-9 (MPHQ-9) for ecological momentary assessment in depressed adults. Psychol Assess. 2026;38(3):159-170. doi:10.1037/pas0001431
This study evaluated the psychometric properties of the Mobile Patient Health Questionnaire-9 (MPHQ-9), an ecological momentary assessment (EMA) adaptation of the Patient Health Questionnaire-9 (PHQ-9), with a focus on internal consistency, longitudinal stability, and convergent validity. This additional analysis (N=280) used data from the Tracking Depression Study (N=300), which included adults (at least 18 years old) in the United States with a current diagnosis of major depressive disorder. Individuals with active suicide risk, mania, or psychosis were excluded. Participants completed the PHQ-9 during screening and again at the end of the 90-day study. Throughout the study, the MLife mobile application prompted participants to complete the MPHQ-9 three times daily. For the present analyses, participants were expected to complete 42 MPHQ-9 assessments during both the first two weeks (T1) and the last two weeks (T2) of the study. Average completion rates were 37.51 assessments (SD = 9.09) at T1 and 33.10 assessments (SD = 9.24) at T2. Participants completed at least one assessment on an average of 12.37 days (SD = 2.18) at T1 and 12.44 days (SD = 2.47) at T2. The MPHQ-9 demonstrated strong psychometric performance, including higher internal consistency and greater stability than the traditional PHQ-9. The aggregated MPHQ-9 also showed strong convergent validity. Although one reliability approach suggested substantial within-person reliability, another indicated only fair reliability, with slightly less than half of observed within-person fluctuations considered reliable. Overall, findings provide preliminary evidence that the MPHQ-9 is a valid EMA measure of depression and may offer advantages over retrospective assessments by reducing recall bias and capturing symptom patterns and variability across different times of day and across days.