• 1 Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
  • 2 Schulich Library of Physical Sciences, Life Sciences, and Engineering, McGill University, Montreal, Quebec, Canada
  • 3 Department of Clinical, Neuro and Developmental Psychology, Amsterdam Public Health Research Institute, Vrije Universiteit, Amsterdam, the Netherlands
  • 4 Hull York Medical School and the Department of Health Sciences, University of York, Heslington, York, UK
  • 5 Department of Medicine, Department of Health Research and Policy, Department of Biomedical Data Science, Department of Statistics, Stanford University, Stanford, California, USA
  • 6 Library, Concordia University, Montréal, Québec, Canada
  • 7 Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada
  • 8 Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
  • 9 Department of Psychiatry, Makerere University College of Health Sciences, Kampala, Uganda
  • 10 Department of General Practice and Primary Health Care, University of Auckland, Auckland, New Zealand
  • 11 Louis and Gabi Weisfeld School of Social Work, Bar Ilan University, Ramat Gan, Israel
  • 12 Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
  • 13 Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, USA
  • 14 Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, The Australian National University, Canberra, Australia
  • 15 Centre for Brain and Mental Health Research, University of Newcastle, New South Wales, Australia
  • 16 Department of Neurosciences and Behavior, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
  • 17 Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (SAR), China
  • 18 Department of Pediatrics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
  • 19 Department of Psychiatry, University of Rochester Medical Center, New York, USA
  • 20 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, the Netherlands
  • 21 Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
  • 22 Department of Psychosomatic Medicine, Center for Internal Medicine and Dermatology, Charité - Universitätsmedizin Berlin, Berlin, Germany
  • 23 Department of Child & Adolescent Psychiatry, Institute of Mental Health, Singapore, Singapore
  • 24 Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
  • 25 School of Social Work, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
  • 26 Global and Community Mental Health Research Group, Department of Psychology, Faculty of Social Sciences, University of Macau, Macau Special Administrative Region, China
  • 27 City of Minneapolis Health Department, Minneapolis, Minnesota, USA
  • 28 Department of Medical Psychology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
  • 29 Depression Research Center of the German Depression Foundation and Department of Psychiatry, Psychosomatics and Psychotherapy, Goethe University, Frankfurt, Germany
  • 30 School of Psychology, University of Queensland, Brisbane, Queensland, Australia
  • 31 STAR-Stress, Anxiety & Resilience Consultants, Chicago, Illinois, USA
  • 32 Department of Psychiatry, University of Ioannina, Ioannina, Greece
  • 33 Department of Psychiatry, Faculty of Medicine, Shimane University, Shimane, Japan
  • 34 School of Psychology, University of New South Wales, Sydney, Australia
  • 35 Department of Psychological Medicine, Tan Tock Seng Hospital, Singapore, Singapore
  • 36 Department of Psychiatry, Amsterdam UMC, Vrije Universiteit, Amsterdam Public Health Research Institute, Amsterdam, the Netherlands
  • 37 Programme in Health Services & Systems Research, Duke-NUS Medical School, Singapore, Singapore
  • 38 Department of Psychiatry, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
  • 39 Department of Psychosomatic Medicine and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
  • 40 Department of Nursing, St. Joseph's College, Standish, Maine, USA
  • 41 Department of Psychiatry, Faculty of Medicine and Health Sciences, Cancer Resource & Education Centre, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
  • 42 Post-graduate Program in Epidemiology, Federal University of Pelotas, Pelotas, RS, Brazil
  • 43 Department of Clinical Psychology, Graduate School of Niigata Seiryo University, Niigata, Japan
  • 44 Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, USA
  • 45 Department of Epidemiology, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
  • 46 Department of Adult Psychiatry, University Hospitals Leuven, Leuven, Belgium
  • 47 Centre for Behavioural Sciences and Mental Health, Italian National Institute of Health, Rome, Italy
  • 48 Department of Psychiatry and Psychotherapy, University Medical Center Freiburg, Freiburg, Germany
  • 49 Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburg, Edinburgh, Scotland, UK
  • 50 Department of Family Medicine, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
  • 51 Allina Health, Minneapolis, Minnesota, USA
  • 52 Centre for Women's Mental Health, Royal Women's Hospital, Parkville, Melbourne, Australia
  • 53 School of Medicine and Public Health, University of Newcastle, New South Wales, Newcastle, Australia
  • 54 Department of General Practice, Amsterdam Institute for General Practice and Public Health, Amsterdam University Medical Centers, location AMC, Amsterdam, the Netherlands
  • 55 Monash University, Melbourne, Australia
  • 56 Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, USA
  • 57 Florence Nightingale Faculty of Nursing, Midwifery & Palliative Care, King's College London, London, UK
  • 58 Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Ogawa-Higashi, Kodaira, Tokyo, Japan
  • 59 Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montréal, Québec, Canada
Psychol Med, 2020 Jun;50(8):1368-1380.
PMID: 31298180 DOI: 10.1017/S0033291719001314


BACKGROUND: Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.

METHODS: We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.

RESULTS: 16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (-0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).

CONCLUSIONS: PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.