# WMH Cross National Sample ## expand\_more Sort**Country****Survey1****Years****Response Rate****Sample Size**Argentina AMHES 2015 77.3% 3927 Australia NSMHWB 2007 60.0% 8841 Belgium ESEMeD 2001-2 50.6% 2419 Brazil Sao Paulo Megacity 2005-8 81.3% 5037 Bulgaria NSHS 2002-6 72.0% 5318 Bulgaria 2 NSHS - 2 2016-17 61.0% 1508 Colombia NSMH 2003 87.7% 4426 Colombia - Medellín MMHHS 2011-12 97.2% 3261 France ESEMeD 2001-2 45.9% 2894 Germany ESEMeD 2002-3 57.8% 3555 Hong Kong, SAR of PRC2 WMHHK 2022-24 25.5% 3053 Iraq IMHS 2006-7 95.2% 4332 Israel NHS 2003-4 72.6% 4859 Italy ESEMeD 2001-2 71.3% 4712 Japan WMHJ - Region 1 2002-3 56.4% 1663 WMHJ - Region 2 2003-4 55.1% 1323 WMHJ - Regions 3- 5 2004-6 42.6% 1143 Lebanon LEBANON 2002-3 70.0% 2857 Mexico M-NCS 2001-2 76.6% 5782 Nepal Chitwan Valley Family Survey 2016-18 86% 9150 Netherlands ESEMeD 2002-3 56.4% 2372 New Zealand NZMHS 2004-5 73.3% 12992 Nigeria NSMHW 2002-4 79.3% 6752 Northern Ireland NIMHS 2005-8 68.4% 4340 Peru EMSMP 2004-5 90.2% 3930 The Philippines NSMHW 2021-22 76.7% 9857 Poland EZOP 2010-11 50.4% 10081 Poland 2 EZOP-2 2018-19 63.5% 11998 Portugal NMHS 2008-9 57.3% 3849 PRC2 Shenzhen Shenzhen-WMH 2005-7 80.0% 7134 Qatar WMHQ 2019-22 19.2% 5195 Romania RMHS 2005-6 70.9% 2357 Saudi Arabia SNMHS 2013-16 61.0% 4004 South Africa SASH 2002-4 87.1% 4351 Spain ESEMeD 2001-2 78.6% 5473 Spain - Murcia PEGASUS-Murcia 2010-12 67.4 % 2621 Turkey WMH-TR 2019-20 44.0% 1790 Ukraine CMDPSD 2002 78.3% 4725 United States NCS-R 2001-3 70.9% 9282 1 AMHES (Argentina Mental Health Epidemiologic Survey); NSMHWB (Australia - National Survey of Mental Health and Wellbeing); ESEMeD (The European Study Of The Epidemiology Of Mental Disorders); NSHS (Bulgaria National Survey of Health and Stress); NSMH (The Colombian National Study of Mental Health); MMHHS (Medellín Mental Health Household Study); IMHS (Iraq Mental Health Survey); NHS (Israel National Health Survey); WMHJ 2002-2003 (World Mental Health Japan Survey); LEBANON (Lebanese Evaluation of the Burden of Ailments and Needs Of the Nation); M-NCS (The Mexico National Comorbidity Survey); NZMHS (New Zealand Mental Health Survey); NSMHW (The Nigerian Survey of Mental Health and Wellbeing); NIMHS (Northern Ireland Mental Health Survey); 1 AMHES (Argentina Mental Health Epidemiologic Survey); NSMHWB (Australia - National Survey of Mental Health and Wellbeing); ESEMeD (The European Study Of The Epidemiology Of Mental Disorders); NSHS (Bulgaria National Survey of Health and Stress); NSMH (The Colombian National Study of Mental Health); MMHHS (Medellín Mental Health Household Study); IMHS (Iraq Mental Health Survey); NHS (Israel National Health Survey); WMHJ 2002-2003 (World Mental Health Japan Survey); LEBANON (Lebanese Evaluation of the Burden of Ailments and Needs Of the Nation); M-NCS (The Mexico National Comorbidity Survey); NZMHS (New Zealand Mental Health Survey); NSMHW (The Nigerian Survey of Mental Health and Wellbeing); NIMHS (Northern Ireland Mental Health Survey); EMSMP (La Encuesta Mundial de Salud Mental en el Peru); NSMHW (Philippine National Survey of Mental Health and Wellbeing); EZOP (Epidemiology of Mental Health and Access to Care Survey); NMHS (Portugal National Mental Health Survey); RMHS (Romania Mental Health Survey); SNMHS (Saudi National Mental Health Survey); SASH (South Africa Health Survey); PEGASUS-Murcia (Psychiatric Enquiry to General Population in Southeast Spain-Murcia); CMDPSD (Ukraine - Comorbid Mental Disorders during Periods of Social Disruption); NCS-R (The US National Comorbidity Survey Replication). EMSMP (La Encuesta Mundial de Salud Mental en el Peru); NSMHW (Philippine National Survey of Mental Health and Wellbeing); EZOP (Epidemiology of Mental Health and Access to Care Survey); NMHS (Portugal National Mental Health Survey); WMHQ (World Mental Health Qatar Study); RMHS (Romania Mental Health Survey); SNMHS (Saudi National Mental Health Survey); SASH (South Africa Health Survey); PEGASUS-Murcia (Psychiatric Enquiry to General Population in Southeast Spain-Murcia); WMH-TR (World Mental Health Turkey Survey); CMDPSD (Ukraine - Comorbid Mental Disorders during Periods of Social Disruption); NCS-R (The US National Comorbidity Survey Replication). 2 PRC - People's Republic of China --- Most WMH surveys are based on stratified multistage clustered area probability household samples in which samples of areas equivalent to counties or municipalities in the US were selected in the first stage followed by one or more subsequent stages of geographic sampling (e.g., towns within counties, blocks within towns, households within blocks) to arrive at a sample of households, in each of which a listing of household members was created and one or two people were selected from this listing to be interviewed. No substitution was allowed when the originally sampled household resident could not be interviewed. These household samples were selected from Census area data in all countries other than France (where telephone directories were used to select households) and the Netherlands (where postal registries were used to select households). Several WMH surveys (Belgium, Germany, Italy, Poland, Poland 2, Spain-Murcia) used municipal resident registries to select respondents without listing households. The Japanese sample is the only totally un-clustered sample, with households randomly selected in each of the 11 metropolitan areas and one random respondent selected in each sample household. The sample for the Qatar survey was drawn from a national list of cellular telephone numbers. --- Please follow the link for [country-specific 4-category education variable (PDF)](/sites/g/files/omnuum8166/files/2026-03/analyst_education4.pdf "Country Specific 4 Category Variable") Please follow this link for more information about [WMH ethics procedures and informed consent (PDF)](/sites/g/files/omnuum8166/files/2026-03/IRB_ethics_approval_WMH-CIDI.pdf "WMH Ethics Procedures and Informed Consent") [Country Compare spreadsheet (XLXS):](/sites/g/files/omnuum8166/files/2026-03/2025-10-03_Analyst_Country_Compare.xlsx "Country Compare Document") This document compares disorders across countries, listing, among other things, the hierarchies applied and whether the disorder was assessed in the Part I sample, Part II sample, age-restricted sample, or whether it was assessed at all. For DSM-4 disorders, please refer to this **DSM-4 (Old CIDI)** worksheet. Similarly, for DSM-5 disorders, please refer to this **DSM-5 (New CIDI)** worksheet.