eTable 1. Details of included studies.
| Study | When data collected | Where data collected | Sample type | Definition of homelessness | Recruitment strategy | Accommodation status | Sample size | Tools | Diagnostic criteria | Mean age | Percentage female | Professional interviewer | Participation rate, % |
| Fichter, 1996, 1997, 1999 (32, 37, 39); Meller, 2000 (29) | 1989 to 1990 | Munich (male participants only) | Representative random sample | No home in Munich area for at least 30 days before interview | Common locations for the homeless (soup kitchens, emergency shelters, outdoor locations, etc.) | 3 categories: I. outdoors (49) II. with beds (25) III. meals/advice (72) |
146 | DIS-III, MMSE | DSM-III | 43 | 0 | No*2 | 85 |
| Greifenhagen, 1997(31); Meller, 2000 (29) | 1989 to 1990 | Munich (female participants only) | Representative random sample | No home in Munich area for at least 30 days before interview (except women‘s shelters) | Common locations for the homeless (soup kitchens, emergency shelters, outdoor locations, etc.) | 3 categories: I. outdoors (12) II. with beds (14) III. meals/advice (6) |
32 | DIS-III, MMSE | DSM-III | 35.5 | 100 | No*2 | 89 |
| Reker, 1997 (26) | 1990 | Münster | Data collected on all residents of a shelter for homeless men (stay >3 months) | >3 months living in city shelter | City shelter for homeless men | City shelter for homeless men (52) | 52 | Semi-structured interview, GAF | ICD-10 | 45.0 | 0 | Yes | 78.8 |
| Podschus, 1995 (28); Dufeu, 1996 (40) | 1993 to 1994 | Berlin | Random sample (restaurant for the homeless) | Section 72 of the German FWA: homelessness due to social situation | City mission soup kitchen | Sleeping rough (25), boarding houses (46), with friends (8), emergency accommodation (3), hostel (3), sheltered accommodation (2) |
72 | CIDI*1, MMSE, GAF | ICD-10 | 40.5 | 0 | Not stated | 85 |
| Fichter, 2006 (36); Quadflieg, 2007 (27) | 1994 to 1996 | Munich | Data collected longitudinally on all homeless people in line with allocation of living space | At least one of the following in the last 30 days: (1) accommodation in home of friends or relatives with at least 3 changes of accommodation, (2) accommodation at emergency shelter for the homeless, (3) accommodation in places not intended as such (e.g. parks) | Recruitment in line with accommodation (homes with therapeutic assistance, homeless shelters, social housing) | No information on previous housing status, at time of questioning in homes with therapeutic assistance (6), homeless shelters (75), social housing (13) | 129 | SCID, MMSE, FPI-R (emotional lability scale), GAF, SCL-90-R (scales: compulsiveness, insecurity on social contact, depression, anxiety, aggression, hostility) | DSM-IV | 44.4 | 15.5 | Not stated | Not stated |
| Fichter, 1999, 2000, 2001, 2003, 2005 (11, 33 to 35, 38) | 1994 to 1996 | Munich | Representative random sample | No home in Munich area for at least 30 days before interview | Common locations for the homeless (soup kitchens, emergency shelters, outdoor locations, etc.) | 3 categories: I. outdoors (12) II. with beds (158) III. meals/advice (95) |
265 | SCID, MMSE | DSM-IV | 44.7 | 0 | No*2 | 88 |
| Völlm, 2004 (12, 21) | 1997 to 1999 | Mannheim | repräsentative Zufallsstichprobe | No room or home on basis of rent agreement (refugees excluded) | Common locations for the homeless (streets, shelters, soup kitchens, advice centers) | 3 categories: I. sleeping rough (18) II. homes and shelters for the homeless (66) III. hostels providing rehabilitation/therapy (18) |
102 | SCID, MLDL, physical examination | DSM-IV | 40.0 | 13,7 | Not stated | Not stated |
| Salize, 2001, 2002 (23, 24, e3) | 1996 | Dortmund | Representative random sample | Only „literally homeless“ as defined by Rossi (e2) | Advice centers and city shelters | „Sleeping rough“ (82) | 82 | CIDI*1, semi-structured interview in line with AMDP, physical examination | ICD-10 | 41.4 | 0 | Yes | 81.5 |
| Torchalla, 2004 (22) | 2001 | Tübingen | Data collected on all homeless women in Tübingen | Section 72 of German FWA: persons without adequate or permanent accommodation, extended to less obvious forms, e.g. shared accommodation | Advice centers, recruitment by professional support workers | Hospital (1), motor home (2), friends/acquaintances (6), women‘s shelter (5), assigned accommodation (2) | 17 | SCID, BeLP | DSM-IV | 29 | 100 | Not stated | 77.3 |
| Längle, 2005 (30) | 2002 to 2003 | Tübingen | Data collected on all appropriate individuals | Section 72 of German FWA: persons without adequate or permanent accommodation | Common locations for the homeless (soup kitchens, emergency shelters, outdoor locations, etc.), recruitment by professional support workers | Homeless shelters and emergency accommodation | 91 | SCID, BML, MMSE, MWT-B, WAIS-R, GAF, BeLP | ICD-10 | 40.0 | 0 | Yes | 60. 3 |
| Brönner, 2013 (e1); Jahn 2014 (2) | 2010 to 2012 | Munich | Representative random sample | Residents of homeless shelters in Munich and surrounding areas (long-term assistance, reintegration, low-threshold assistance, assistance in line with Section 53 et seq. of SSC XII, counseling/emergency accommodation, sheltered accommodation) | Facilities for the homeless in Munich and surrounding areas | Long-term assistance (61), housing according to Section 53 (52), low-threshold assistance (40), reintegration (32), emergency accommodation (28), sheltered accommodation complexes (19) | 232 | SCID, MALT, BDI, mini ICF-APP, SF-36, B-L, CGI, MMSE, WAIS | DSM-IV | 48.1 | 20,7 | Not stated | 55 |
*1Parts on dependency disorders and psychosomatic disorders; *2Trained laypeople
AMDP, Working Group for Methods and Documentation in Psychiatry (Arbeitsgemeinschaft für Methodik und Dokumentation in der Psychiatrie); BDI: Beck Depression Inventory; BeLP: Berlin Quality of Life Profile (Berliner Lebensqualitätsprofil); B-L: Complaints List (Beschwerdeliste): BML: Brunswick List of Features (Braunschweiger Merkmalsliste) for chronic, multiply-impaired alcoholics FWA: Federal Welfare Act; CIDI: Composite International Diagnostic Interview; CGI: Clinical Global Impression Scale; DIS: Diagnostic Interview Schedule; FPI-R: Freiburg Personality Inventory (Freiburger Persönlichkeitsinventar) – Revision; GAF: Global Assessment of Functioning; WAIS-R: Wechsler Adult Intelligence Scale – Revision; MALT: Munich Alcoholism Test (Münchner Alkoholismustest); Mini-ICF-APP: Mini-ICF-APP Social Functioning Scale; MLDL: Munich Quality of Life List (Münchner Lebensqualitäts-Dimensionen-Liste); MMSE: Mini-Mental Status Examination; MWT-B: Multiple-Choice Vocabulary Test (Mehrfachwahl-Wortschatztest), version B; SCID: Structured Clinical Interview for DSM; SCL-90-R: Symptom Checklist 90 – Revised; SF-36: Short-Form Health Survey; SSC: Social Security Code; WAIS: Wechsler Adult Intelligence Scale