1 Lady Davis Institute for Medical Research,Jewish General Hospital,Montréal,Québec,CanadaandDepartment of Epidemiology, Biostatistics and Occupational Health,McGill University,Montréal,Québec,Canada.
2 Department of Epidemiology, Biostatistics and Occupational Health,McGill University,Montréal,Québec,Canada;Department of Medicine,McGill University,Montréal,Québec,CanadaandRespiratory Epidemiology and Clinical Research Unit,McGill University Health Centre,Montréal,Québec,Canada.
3 Lady Davis Institute for Medical Research,Jewish General Hospital,Montréal,Québec,Canada.
4 Lady Davis Institute for Medical Research,Jewish General Hospital,Montréal,Québec,CanadaandDepartment of Psychology,McGill University,Montréal,Québec,Canada.
5 Department of Clinical, Neuro and Developmental Psychology,EMGO Institute, VU University,Amsterdam,the Netherlands.
6 Hull York Medical School and the Department of Health Sciences,University of York,York,UK.
7 Department of Medicine,Department of Health Research and Policy,Department of Biomedical Data Science,Department of Statistics,Stanford University,Stanford,California,USA.
8 Library,Concordia University,Montréal,Québec,Canada.
9 Department of Community Health Sciences,University of Calgary,Calgary,Alberta,Canada and Hotchkiss Brain Institute and O'Brien Institute for Public Health, University of Calgary,Calgary,Alberta,Canada.
10 Lady Davis Institute for Medical Research,Jewish General Hospital,Montréal,Québec,CanadaandDepartment of Mathematics and Statistics,McGill University,Montréal,Québec,Canada.
11 Department of Medicine,Johns Hopkins University School of Medicine,Baltimore,Maryland,USA.
12 Department of Psychiatry,Makerere University College of Health Sciences,Kampala,Uganda.
13 Department of General Practice and Primary Health Care,University of Auckland,New Zealand.
14 Louis and Gabi Weisfeld School of Social Work,Bar Ilan University,Ramat Gan,Israel.
15 Endocrine Research Center,Institute of Endocrinology and Metabolism, Iran University of Medical Sciences,Tehran,Iran.
16 Lady Davis Institute for Medical Research,Jewish General Hospital,Montréal,Québec,CanadaandDepartment of Medicine,McGill University,Montréal,Québec,Canada.
17 Kbo-Lech-Mangfall-Klinik Garmisch-Partenkirchen,Klinik für Psychiatrie,Psychotherapie & Psychosomatik,Lehrkrankenhaus der Technischen Universität München,Munich,Germany.
18 Department of Rehabilitation Medicine,University of Washington,Seattle,Washington,USA.
19 Centre for Research on Ageing, Health and Wellbeing,Research School of Population Health,The Australian National University,Canberra,Australia;Centre for Mental Health,Melbourne School of Population and Global Health,University of Melbourne,Melbourne,AustraliaandMelbourne Institute of Applied Economic and Social Research, University of Melbourne,Melbourne,Australia.
20 Centre for Translational Neuroscience and Mental Health,University of Newcastle,New South Wales,Australia.
21 Department of Neurosciences and Behavior,Ribeirão Preto Medical School,University of São Paulo,Ribeirão Preto,Brazil.
22 Department of Medicine and Therapeutics,Prince of Wales Hospital,The Chinese University of Hong Kong,Hong Kong Special Administrative Region,China;Asia Diabetes Foundation,Prince of Wales Hospital,Hong Kong Special Administrative Region,China and Hong Kong Institute of Diabetes and Obesity,Hong Kong Special Administrative Region,China.
23 Department of Pediatrics,University of North Carolina at Chapel Hill School of Medicine,Chapel

Background: Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.AimsTo evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.

Method: Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.

Results: A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15-3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores =6) as having major depression (OR = 3.13; 95% CI = 0.98-10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7-15) (OR = 0.96; 95% CI = 0.56-1.66) and significantly less likely for high-level symptoms (PHQ-9 scores =16) (OR = 0.50; 95% CI = 0.26-0.97).

Conclusions: The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.Declaration of interestDrs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.