***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
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    Input: INTRODUCTION AND AIMS Homelessness is associated with increased prevalence of mental health disorders , substance use disorders and mental health/substance use disorder comorbidity in the United States of America . Gay , bisexual and other men who have sex with men ( MSM ) living in the United States are at increased risk for homelessness , and have also evidence d elevated mental health and substance use disorder prevalence relative to their non-MSM male counterparts . DESIGN AND METHODS Secondary analysis of data from a r and omised controlled trial estimating the diagnostic prevalence of substance use/mental health disorder comorbidity among a sample of homeless , substance-dependent MSM ( DSM-IV verified ; n = 131 ) . RESULTS The most prevalent substance use/mental health disorder comorbidities were stimulant dependence comorbid with at least one depressive disorder ( 28 % ) , alcohol dependence comorbid with at least one depressive disorder ( 26 % ) and stimulant dependence comorbid with antisocial personality disorder ( 25 % ) . DISCUSSION AND CONCLUSIONS Diagnostic depression and antisocial personality disorder both demonstrated high rates of prevalence among homeless , substance-dependent ( particularly stimulant and alcohol dependent ) MSM . [ Fletcher JB , Reback CJ . Mental health disorders among homeless , substance-dependent men who have sex with men . Drug Alcohol Rev 2016;36:555 - 559 ] Metholodogy This study examined the prevalence and correlates of  mental illness in homeless people in Hong Kong and explored the barriers preventing their access to health care . Ninety-seven Cantonese-speaking Chinese who were homeless during the study period were selected at r and om from the records of the three organisations serving the homeless population . The response rate was 69 % . Seventeen subjects could not give valid consent due to their poor mental state , so their responses were excluded from the data analysis . A psychiatrist administered the  Structured Clinical Interview for DSM-IV Axis-I disorders ( SCID-I )  and the  Mini -Mental State Examination .  Consensus diagnoses for subjects who could not complete the SCID-I were established by three independent psychiatrists . Findings The point prevalence of mental illness was 56 % . Seventy-one percent of the subjects had a lifetime history of mental illness , 30 % had a mood disorder , 25 % had an alcohol use disorder , 25 % had a substance use disorder , 10 % had a psychotic disorder , 10 % had an anxiety disorder and 6 % had dementia . Forty-one percent of the subjects with mental illness had undergone a previous psychiatric assessment . Only 13 % of the subjects with mental illness were receiving psychiatric care at the time of interview . The prevalence of psychotic disorders , dementia and the rate of under treatment are hugely underestimated , as a significant proportion ( 18 % ) of the subjects initially selected were too ill to give consent to join the study . Conclusion The low treatment rate and the presence of this severely ill and unreached group of homeless people reflect the fact that the current mode of service delivery is failing to support the most severely ill homeless individuals BACKGROUND Very little is known about the mental health of homeless women . The present study is one of the first to focus on psychiatric diagnosis and comorbidity in a population of homeless women systematic ally interviewed with a structured instrument . METHOD Three hundred homeless women r and omly selected from St. Louis shelters were interviewed using the Diagnostic Interview Schedule ( DIS ) . RESULTS The population of homeless women in St. Louis is predominantly young adult , single , and black ; most have young children and average nearly a high school education . Schizophrenia and bipolar affective disorder account for only a small portion of the mental illness in these women . Nearly one in three has a history of substance abuse , with drug abuse being more prevalent than alcoholism . One third of the sample met lifetime criteria for posttraumatic stress disorder . One fourth of the women have received  inpatient psychiatric care  , and the majority with a nonsubstance Axis I diagnosis have received some  mental health treatment .  CONCLUSION Although major mental illness is overrepresented among these homeless women , the majority do not suffer from major mental illness . Despite the severity of the stressors these women face , the large numbers escaping psychiatric disorders speak to their resilience and to the likelihood that important factors other than mental illness contribute to their homelessness . Future studies to examine positive outcomes and investigate protective factors might provide a valuable source of information on coping with the stresses associated with homelessness and point to more effective interventions Introduction Quality assessment of included studies is an important component of systematic review s. Objective The authors investigated inter-rater and test – retest reliability for quality assessment s conducted by inexperienced student raters . Design Student raters received a training session on quality assessment using the Jadad Scale for r and omised controlled trials and the Newcastle – Ottawa Scale ( NOS ) for observational studies . Raters were r and omly assigned into five pairs and they each independently rated the quality of 13–20 articles . These articles were drawn from a pool of 78 papers examining cognitive impairment following electroconvulsive therapy to treat major depressive disorder . The articles were r and omly distributed to the raters . Two months later , each rater re-assessed the quality of half of their assigned articles . Setting McMaster Integrative Neuroscience Discovery and Study Program . Participants 10 students taking McMaster Integrative Neuroscience Discovery and Study Program courses . Main outcome measures The authors measured inter-rater reliability using κ and the intraclass correlation coefficient type 2,1 or ICC(2,1 ) . The authors measured test – retest reliability using ICC(2,1 ) . Results Inter-rater reliability varied by scale question . For the six-item Jadad Scale , question -specific κs ranged from 0.13 ( 95 % CI −0.11 to 0.37 ) to 0.56 ( 95 % CI 0.29 to 0.83 ) . The ranges were −0.14 ( 95 % CI −0.28 to 0.00 ) to 0.39 ( 95 % CI −0.02 to 0.81 ) for the NOS cohort and −0.20 ( 95 % CI −0.49 to 0.09 ) to 1.00 ( 95 % CI 1.00 to 1.00 ) for the NOS case – control . For overall scores on the six-item Jadad Scale , ICC(2,1)s for inter-rater and test – retest reliability ( accounting for systematic differences between raters ) were 0.32 ( 95 % CI 0.08 to 0.52 ) and 0.55 ( 95 % CI 0.41 to 0.67 ) , respectively . Corresponding ICC(2,1)s for the NOS cohort were −0.19 ( 95 % CI −0.67 to 0.35 ) and 0.62 ( 95 % CI 0.25 to 0.83 ) , and for the NOS case – control , the ICC(2,1)s were 0.46 ( 95 % CI −0.13 to 0.92 ) and 0.83 ( 95 % CI 0.48 to 0.95 ) . Conclusions Inter-rater reliability was generally poor to fair and test – retest reliability was fair to excellent . A pilot rating phase following rater training may be one way to improve agreement Background : Homelessness is a growing problem in the cities of the western world , and homeless people have a plethora of mental health and social difficulties . These are , nevertheless , difficult to evaluate epidemiologically . Method : In this paper we present a population survey using the Composite International Diagnostic Interview ( CIDI ) conducted in the city of Paris in winter 1996 on a representative sample of 838 homeless people .  Night shelters as well as food kitchens were r and omly sample d , and the mean response rate was around 65 % . Results : The sample was relatively young and predominantly male ( 85 % ) . Forty percent were born outside France , 96 % had worked at some time , and one-third reported no re sources at all . The lifetime prevalence of psychiatric disorders was 57.9 % , while the 1-year prevalence was 29.1 % . For definite psychotic disorders , prevalence was 16 % ( lifetime ) and 6 % ( 1-year ) . Generally , this Parisian homeless population had some access to care : in the preceding 6 months 57.7 % of them had been medically attended and 14.2 % of these had been hospitalised . The survey was cross-sectional , and did not evaluate regular access to care or the quality of care . Conclusions : The implication s for health and social systems are discussed in the light of comparisons with European and North American data Objective : To determine whether the prevalence of schizophrenia among the homeless population of Edinburgh resident in hostels has changed between 1966 and 1992 . Design : Comparison of two cross sectional surveys . Setting s -- Hostels for homeless people in Edinburgh . Subjects -- In 1966 a r and om sample of 98 residents of three common lodging houses . In 1992 a r and om sample of 198 residents of nine hostels . Main outcome measure -- Prevalence of schizophrenia . Results : The prevalence of schizophrenia in 1992 was 12/136 ( 9 % ) compared with 20/79 ( 25 % ) in 1966 ( odds ratio 0.29 ; 95 % confidence interval 0.13 to 0.62 ; P=0.001 ) . Adjustment for confounding by age , current hostel , and duration of unemployment by means of logistic regression produced an adjusted odds ratio of 0.22 ( 0.08 to 0.58 ) . Conclusions : The prevalence of schizophrenia was lower in 1992 even after other changes in the population resident in hostels occurring between 1966 and 1992 were taken into account . The findings are not consistent with an increase in the prevalence of schizophrenia  among homeless people despite a 66 % reduction in adult psychiatric beds in the region during 1966 - 92 Objective : International studies indicate high prevalence rates of post-traumatic stress disorder within homeless population s. In Australia , studies indicate high rates of trauma among homeless adults , yet post-traumatic stress disorder has not been investigated in homeless Australian adults . The primary aim of this project was to determine the prevalence of  post-traumatic stress disorder among homeless adults in Sydney . Further , another aim of the study was to determine whether the onset of post-traumatic stress disorder preceded the first episode of homelessness or was a consequence of homelessness . Method : The sample consisted of 70 homeless men and women aged 18–73 years , who were r and omly sample d through eight homeless services . A computer-assisted face-to-face structured clinical interview was conducted with each participant . Lifetime prevalence of post-traumatic stress disorder was determined via the Composite International Diagnostic Interview . Results : The majority of the sample had experienced at least one traumatic event in their lifetime ( 98 % ) . Indeed , the mean number of traumas per person was six . The 12 month prevalence of post-traumatic stress disorder was higher among homeless adults in Sydney in comparison to the Australian general population ( 41 % vs 1.5 % ) . But 79 % of the sample had a lifetime prevalence of post-traumatic stress . In 59 % of cases , the onset of post-traumatic stress disorder preceded the age of the first reported homeless episode . Conclusions : Homeless adults in Sydney frequently experience trauma and post-traumatic stress disorder . The study found that trauma and post-traumatic stress disorder more often precede homelessness , but re-victimization is common . These findings highlight the high mental health needs among homeless people and have implication s for services for homeless people A study of homeless people in Baltimore , Md , focused on their health and other characteristics , with special emphasis on their needs for services . In the first stage , 298 men and 230 women were r and omly selected from the missions , shelters , and jail in Baltimore to respond to a baseline interview that provided extensive sociodemographic and health-related data . In the second stage , a sub sample of 203 subjects was r and omly selected from the baseline survey respondents to have systematic psychiatric and physical examinations . Data are presented from both stages . Data from the first stage demonstrate , among other things , the high levels of disaffiliation of this population and their heavy involvement in substance abuse . Data from the clinical examinations demonstrate the high prevalence of mental illnesses and other psychiatric disorders and of a wide range of physical disorders and confirm the high prevalence of alcohol abuse disorders . The high rates of comorbidity of these conditions is demonstrated and data are provided on the subjects ' needs for mental health and substance abuse services Purpose Previous cross-sectional studies have indicated that homeless individuals may present with high rates of suicidal ideation , which are strongly associated with completed suicide . We conducted the first known longitudinal study of suicidal ideation in the homeless . Methods We used data collected over 24 months in the Vancouver At Home project ( N = 497 ) , comprised two r and omized-controlled trials of housing interventions for homeless individuals with mental disorders . Presence of suicidal ideation was determined using the Colorado symptom index . Results Suicidal ideation significantly decreased over time [ odds ratio ( OR ) = 0.31 at 24 months , 95 % confidence interval ( CI ) 0.21–0.46 ] . Baseline diagn 
    Output:
    
Conclusion This systematic review and meta- analysis revealed that schizophrenia and other psychotic disorders are highly prevalent among homeless people , indicating an urgent need for studies to help develop better mechanisms of prevention , detection as well as treatment of those disorders among homeless people