Screening for depression with the Patient Health Questionnaire-2 (PHQ-2) alone and in combination with the PHQ-9: individual participant data meta-analysis

Article type
Authors
Levis B1, Sun Y1, He C1, Wu Y1, Krishnan A1, Bhandari PM1, Neupane D1, Imran M1, Brehaut E1, Negeri ZF1, Fischer FH2, Benedetti A1, Thombs BD1
1McGill University
2Charité - Universitätsmedizin Berlin
Abstract
Background: The Patient Health Questionnaire-2 (PHQ-2) depression screening tool includes items that assess frequency of depressed mood and anhedonia in the past two weeks. It can be used alone or as a first step to identify patients for evaluation with the full Patient Health Questionnaire-9 (PHQ-9). Meta-analyses on PHQ-2 accuracy have been limited by including only published data and by not examining accuracy for different reference standards, in participant subgroups, or in combination with the PHQ-9, as it is commonly used in practice. Individual participant data meta-analysis (IPDMA), which synthesizes participant-level data from primary studies rather than summary results from study reports, has the potential to overcome these challenges.

Objectives: To use IPDMA to evaluate the accuracy of the PHQ-2 alone and in combination with the PHQ-9 for screening to detect major depression.

Methods: Medline, Medline In-Process & Other Non-Indexed Citations, PsycINFO, and Web of Science were searched from Jan 1, 2000 to May 9, 2018 for datasets that compared PHQ scores to major depression classification based on a validated diagnostic interview. Bivariate random-effects meta-analysis was used to estimate sensitivity and specificity compared to semi-structured, fully structured (Mini International Neuropsychiatric Interview [MINI] excluded), and MINI diagnostic interviews, separately, and in participant subgroups based on age, sex, country human development index and recruitment setting.

Results: Individual participant data were obtained from 100 of 136 eligible studies (44,318 participants, 4,572 major depression cases). Among studies that used semi-structured interviews, PHQ-2 sensitivity and specificity were 0.91 and 0.67 for cutoff ≥2 and 0.72 and 0.85 for cutoff ≥3. Sensitivity was significantly greater for semi-structured versus fully structured interviews. Specificity was not significantly different across interviews. There were no significant differences in accuracy across subgroups. For semi-structured interviews, sensitivity for PHQ-2 ≥2 followed by PHQ-9 ≥10 was not significantly different than for PHQ-9 ≥10 alone (0.82 versus 0.86); specificity was significantly but minimally higher (0.87 versus 0.85). The combination reduced the number of participants needing to complete the full PHQ-9 by 57%.

Conclusions: PHQ-2 ≥2 followed by PHQ-9 ≥10 had similar accuracy as PHQ-9 ≥10 alone and reduced the proportion of participants needing to complete the full PHQ-9 by 57%.

Patient or healthcare consumer involvement: There was no direct patient or consumer involvement in this project. However, clinicians considering screening for depression with the PHQ alone or in combination with the PHQ-9 can refer to our web-based knowledge translation tool: depressionscreening100.com/phq-2, which estimates expected numbers of positive screens and true and false screening outcomes based on results from the present IPDMA.