Differences in Adult PHQ9 Administration at KP Northwest by Demographic and Census Factors
information technology, demographics, behavioral and mental health, clinical practice patterns/guidelines, virtual data warehouse, racial/ethnic differences in health and health care, social determinants of health, access to services, patient-reported outcomes/functional status, health promotion, prevention, screening
Background: The Patient Health Questionnaire (PHQ-9) is a depression screener that scores each of the nine DSM-IV depression criteria from the original PRIME-MD. With the increased administration and electronic capture of data from the PHQ-9 instrument, it has added research value to its existing usefulness as a clinical evaluation tool. Recent inclusion in Health Care Systems Research Network’s virtual data warehouse (VDW) means that researchers can look at PHQ-9 data in the context of other important patient health and demographic factors.
Methods: We interrogated the Kaiser Permanente Northwest (KPNW) VDW for demographic, diagnosis, enrollment, and PHQ-9 and U.S. Census data for the years 2014–2015. Age, gender and race/ethnicity were combined with Census education and income, PHQ-9 dates and ICD-9/10 depression diagnoses. Within the sampling frame of all adults aged 18–90 years with any KPNW enrollment in 2014 and 2015, we compared four groups: among patients with a PHQ-9 screening over the study years, those (a) with, and (b) without one or more clinical depression diagnoses; and among patients without a PHQ-9 screening, those (c) with, and (d) without one or more depression diagnoses.
Results: Patients completing the PHQ-9 differed in several ways from adults who did not complete the PHQ-9. The PHQ-9 group was older (mean age: 49.7 vs 45.9 years) and more often female (64.6% vs 49.4%) and non-Hispanic white (82.1% vs 66.7%). A notably lower percentage of PHQ-9 screened patients were non-Hispanic Asian (2.4% vs 4.7% with no screening). As expected, the PHQ-9 group was demographically similar to the group with the depression diagnoses, with some minor differences on gender. Patients with a depression diagnosis and a PHQ-9 administration were slightly more often female compared to those without a PHQ-9 (69.9% vs 66.9%). Census comparisons indicate that patients with a depression diagnosis and a PHQ-9 lived in areas with slightly lower educational attainment versus patients with a depression diagnosis only (28% of adults in their Census area had a bachelor’s degree vs 31% without, respectively). No differences were observed on income.
Conclusion: The PHQ-9 is differentially administered among adult patients at KPNW. But the administration does follow the demographic spectrum of depression.
Crawford P, Lynch F, Clarke G, Simon G. Differences in adult PHQ9 administration at KP Northwest by demographic and census factors. J Patient Cent Res Rev. 2017;4:189-90.