Employment and the associated impact on quality of life in people diagnosed with schizophrenia

Introduction

On a patient level, employment plays a central role in providing financial income and nonfinancial gains, including social identity, social contacts and support, a means of structuring and occupying time, activity and involvement, and a sense of personal achievement.¹ People with long-term mental illness, including schizophrenia, are sensitive to the negative effects of unemployment, and experience barriers to work, due to stigma, prejudice, and discrimination.¹ Apart from these individual disadvantages, unemployment in people with schizophrenia is economically costly from a societal point of view. The estimated total societal cost of schizophrenia was 6.7 billion pounds in England for the year 2004–2005.² Half of these costs were due to unemployment, absence from work, and premature mortality, amounting to 3.4 billion pounds.

Studies reporting on employment in people with schizophrenia show diverging figures. However, generally employment rates are low. Marwaha and Johnson were the first authors to publish a review on schizophrenia and employment.³ They concluded that there is a wide variation in reported employment rates. Additionally, their study showed that employment is correlated with positive outcomes in social functioning, symptom levels, quality of life (QoL), and self-esteem, but a clear causal relationship was not demonstrated.³

Increasingly, treatment models have focused on the subject of employment in people with schizophrenia. These treatment models strive, among other goals, to increase the individual’s own subjective view of well-being and satisfaction with his or her life. This development is in line with the shift in mental health services from an emphasis on treatment focused on reducing symptoms, based on a narrow notion of health and disease, to a more holistic approach that takes both well-being and functioning into consideration.⁴ However, for people with schizophrenia, there is still a lack of information on the subject of employment and associated health-related QoL (HRQoL).

A previous study has shown that being employed is associated with a markedly better HRQoL for people with schizophrenia.⁵ However, the relationship between being employed and HRQoL may be bidirectional. It is known that the type of employment plays a crucial role in the effect on HRQoL.⁵ For instance, having a voluntary job, in general, means a low income. This may result in relatively poor living conditions and inability to afford social activities. Consequently, this may lead to a diminished HRQoL.^6,7 In addition, although intuitively being employed may lead to increased HRQoL, the converse reasoning is also defendable, that is, having a higher HRQoL indicates being happier, presumably resulting in better capacities to perform daily activities such as a (paid) job. So, there is still a need to further explore the association between employment and HRQoL in schizophrenia.

Firstly, this review assessed the prevalence of employment in people with schizophrenia. Next, we aimed to identify factors associated with being employed in this population. Lastly, we examined the interrelation between being employed and HRQoL that was assessed in the studies under review.

Methods

A literature search was conducted to identify the employment rate in people with schizophrenia. We applied a broad definition of employment as having any job, whether full-time or part-time, and whether competitive or supported employment. In addition, we screened the selected papers for factors associated with being employed and for the interrelationship between being employed and HRQoL.

Search strategy

A systematic literature search was performed in PubMed and PsychInfo, including studies from 2000 until July 1, 2013, including information on employment in representative (groups of) adults diagnosed with schizophrenia. We applied a broad search strategy for identifying studies. Consequently, no criteria concerning study design were applied. The search terms included the Medical Subject Headings (MeSH) terms and Field terms “schizophrenia”, “employment”, “unemployment”, “paid work”, and “work capacity” (Supplementary material). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was followed for the reporting of systematic reviews and meta-analyses.⁸

Selection strategy

The selection of the abstracts was independently performed by two researchers. Discrepancies concerning inclusion or exclusion of an abstract were resolved by discussing the eligibility criteria during plenary meetings. The selection criteria were:

1. Studies published in 2000 or later
2. Studies performed in Western countries, or in Japan or Hong Kong
3. Studies explicitly including people diagnosed with schizophrenia
4. Studies for which information on (un)employment or work was given in the Abstract
5. Case studies, editorial letters, comments, or conference proceedings were excluded
6. Studies reporting on vocational rehabilitation therapy and/or vocational support programs were excluded.
   To determine the eligibility of the full-text articles, the same selection criteria were used. Additional exclusion criteria were:
7. Duplication of source data (ie, studies using samples of other included studies were excluded)
8. Unavailability of the full-text publication
9. Studies including selective samples, eg, the homeless, the convicted, or convenience samples, were excluded
10. Studies including study samples with <100 participants.

First, we presented the prevalence rates of employment in people with schizophrenia, derived from the review. In order to systematically describe the factors associated with employment, a simplified framework was used based on the model of Wilson and Cleary,⁹ which integrates health aspects with functional status and HRQoL. The basic domains of functional status that are commonly measured are physical”, “social”, “role”, and “psychological functioning”.¹⁰ We defined being employed (or unemployed) as part of the functional status. The symptoms are reflected in the disease characteristics of the disorder – these may reflect physical impairment as well as patients’ emotional or cognitive state. Schizophrenia can be described as a syndrome^11,12 characterized by:

• Positive symptoms
• Negative symptoms
• Cognitive symptoms
• Affective symptoms.

Symptoms of schizophrenia are generally described in terms of a positive and a negative dimension. The Positive and Negative Syndrome Scale (PANSS) is, among other instruments, applied for measuring the severity of positive and negative symptoms.¹³ Positive symptoms indicate the occurrence of delusions and hallucinations, while negative symptoms indicate lack of motivation, reduction in spontaneous speech, and social withdrawal. Additionally, there may be a cognitive dimension (difficulties in memory, attention, and executive functioning) and a dimension of affective dysregulation (depression and manic symptoms).

Additionally, the disorder can be described in terms of the age at onset of the disease, the treatment setting, and the duration and course of the disease in terms of remission.

Finally, the functional status may be affected by the co-occurrence of substance and alcohol abuse. Substance abuse has been found to be substantially more prevalent among people with schizophrenia.^14,15 However, prevalence rates of co-occurring dependence or abuse in people with schizophrenia may vary between countries.¹⁶ Substance abuse may worsen the impact of schizophrenia, leading to heightened social adjustment problems.¹⁷

The adapted model takes into account that characteristics of the individual as well as “characteristics of the environment” might impact the experience of symptoms, functional status, and HRQoL, and their relationships. Examples of individual characteristics are age, sex, personality, and individual expectations. With regard to being employed, specifically, motivation and “work readiness” are examples of characteristics of the individual that are probably of importance in finding and maintaining a paid job. Examples of environmental characteristics are social and vocational support, and social security programs. Finally, stigma is also a factor known to diminish the HRQoL of people with schizophrenia, even after recovery of the person.¹⁸

Overall QoL is preferably measured with a generic preference based instrument. In this way, the impact of a condition on HRQoL can be assessed in terms that are relevant to any individual.

Data extraction

Employment rates from the publications were independently extracted by two researchers. Additional data that were collected were the design of the study, the country, the sample size, exclusion criteria, the study setting, demographic information of the study population, clinical measures (eg, PANSS), length of illness, and comorbidity. Additionally, findings concerning associations with employment and concerning employment and HRQoL were recorded.

Results

A total of 789 records were derived from the databases. After removal of duplicates, 701 abstracts were screened. In the search, six review studies were identified. Studies cited in these reviews that were not identified in our search and that met our selection criteria were added (Figure 1).

Figure 1 Flow chart of the literature search. Notes: Reasons for exclusion: 2= not performed in a Western country or Japan or Hong Kong; 3= people with schizophrenia not explicitly included; 4= no (un)employment rate described; 5= case study; 6= study on vocational rehabilitation therapy or vocational support programs; 7= duplicate sources; 8= full text publication unavailable; 9= studies including selective samples or convenience samples were excluded; 10= study sample had <100 subjects.

In total, 43 studies were eligible for analyzing the prevalence of employment (Table 1).

Table 1 Studies reporting on employment in people diagnosed with schizophrenia Abbreviations: CI, confidence interval; FU, follow up; IQ, intelligence quotient; NR, not reported; PANSS, positive and negative syndrome scale; RCT, randomized controlled trial; hr, hour; incl, including; pos, positive; neg, negative.

Employment rate

Employment rates ranged from 4% to 50.4%.^36,52 Generally, employment rates reported in the studies were based on different definitions of employment, eg, the employment in some studies was limited to competitive employment, while in other studies, respondents with supported or sheltered employment were counted too, and in a number of studies, students and/or housewives and those who had volunteer work were also counted as being employed. Additionally, in a number of studies, the definitions of employment that were applied were not reported. Five studies reported only unemployment figures. The studies differed considerably in design, patient settings, and methods of recruitment. Information on the time frame that was used for measuring employment was generally lacking. In the majority of studies, no distinction was made between respondents with schizophrenia, and schizophreniform or schizoaffective disorders. In addition, respondents may have been diagnosed on the basis of different criteria. This fragmented information limited a direct comparison of employment rates reported in these studies. Consequently, these results did not allow performance of a meta-analysis for estimating an average employment rate among people with schizophrenia.

Factors associated with employment

Disease characteristics

Positive symptoms

Marwaha et al⁴¹ examined employment status change during a 2-year European naturalistic study of people with schizophrenia. The researchers found that more positive psychotic symptoms were predictive of job loss.

Negative symptoms

Our review included three studies that reported on associations of negative symptoms and employment. Üçok et al⁵⁵ reported significantly higher PANSS negative symptoms scores in unemployed respondents in comparison with employed respondents. In addition, regression analyses showed that the PANSS negative symptoms score was an independent predictor of unemployment. Bobes et al²³ found that presence of poor rapport and social withdrawal (items of negative PANSS) increased the risk of unemployment. Marwaha et al⁴¹ found that besides characteristics of the onset and duration of the disorder, more severe negative symptoms (PANSS subscale) were significantly negatively associated with the chance of getting work during a 2-year follow-up study.

Cognitive symptoms

Associations of cognitive symptoms and employment were reported in three studies in our review. Giugiario et al³⁰ reported significantly higher scores of verbal memory and more awareness of illness in respondents with competitive employment in comparison with unemployed subjects. In a longitudinal study, Holthausen et al³⁵ found more problems of vocational functioning and significant lower chances of competitive employment in persons with cognitive deficits. Hofer et al³⁴ found that poorer cognitive scores were associated with a reduced probability of competitive employment.

Treatment setting

Another, more indirect indicator of disease severity may be the setting in which people receive care, ie, in- or outpatient care. Most studies included both in- and outpatient treated people. A number of studies did not provide information on the treatment setting. Ten studies included only persons treated in an outpatient setting. Employment rates varied considerably, from 9.5% to 42.6%. No study was found exclusively focusing on inpatients. Only in the study of Ye et al⁶¹ were figures of employment rates for in- and outpatients separately presented. Both the baseline and follow-up employment rates in persons treated as outpatients were almost four times higher in comparison with the rates among inpatients.

Age at onset, course, and duration

Marwaha et al examined predictors of being employed during a 2-year follow-up, using cross-national data derived from Germany, France, and the UK.⁴¹ Later age of illness onset, longer duration of illness, and a continuous illness course were negatively associated with the chance of getting work. Üçok et al reported significantly higher remission rates among employed subjects in comparison with unemployed subjects, and longer duration of remission contributed positively to employment status.⁵⁵ Fourteen studies in our review reported on the duration of the illness.^{20,21,23,24,30,34,36,37,42,44,46,52,56,61} A comparison of the employment rates and the duration of the disorder between these studies did not show a consistent pattern of declining rates with longer duration of the disorder. For example, McCreadie⁴⁴ reported an employment rate of 8% in study participants, with an average duration of 8 years, while Middelboe et al⁴⁶ reported an employment rate of 12% in participants, with an average duration of 15 years.

Alcohol and substance abuse

In the study of Marwaha et al harmful use of alcohol at baseline was a significant predictor of job loss during a 2-year follow up.⁴¹ In our review, 22 studies included information about the proportion of respondents with alcohol or substance abuse. The study of Xie et al⁶⁰ included only patients with co-occurring substance abuse. The employment rate was 6% at baseline and increased to 24% at 3-year follow up. In three studies, respondents with alcohol/substance abuse were excluded.^34,47,52 Employment rates reported in these studies were 43.1% (1-year follow up), 27.8% (baseline), and 23.3% (1-year follow up), respectively. The figures presented in these studies are difficult to interpret given the different definitions of employment in these studies. In addition, in the study of Spellmann et al⁵² no definition of employment was stated.

Characteristics of the individual

Marwaha and Johnson³ reported on a number of demographic factors related to being employed in people with schizophrenia in their review, eg, sex, and marital and accommodation status. However, the authors reported that these associations were not consistently replicated between different studies. Among the studies in our review, Üçok et al⁵⁵ found that younger age, more education, and sex (male) were independent positive predictors of employment. Hofer et al³⁴ found that premorbid school functioning was positively correlated with competitive employment, and older age was found to be a significant negative predictor of employment.

Characteristics of the environment

Studies that examined environmental factors and the subject of employment were limited.

Marwaha et al⁴² conducted a study to compare employment patterns and associated environmental factors between and within three European countries: UK, France, and Germany. Variation in employment rate was found both between countries and between regional sites. The greatest variation was found on the national level, between centers rather than between countries. The authors suggested that social and vocational service factors within and between countries may contribute to this variation. One of these factors may be the availability of vocational services and placements, as was seen in Germany. In two other studies that were performed in Germany, relatively high employment rates were reported.^39,52 The low employment rate among people with schizophrenia in the UK reported by Marwaha et al⁴² and Thornicroft et al⁵³ was not confirmed by the study by Rosen and Garety.⁵⁰ In the latter study, an employment rate of 41.2% (excluding 12% students) was reported.

In the study of Thornicroft et al⁵³ including patients from five different European countries, relatively higher employment rates were found in southern countries (Spain and Italy) in comparison with Denmark and the Netherlands. The authors suggested that differences may be associated with differences in the availability of welfare benefits. Comparative low employment rates (12% in outpatients) in Scandinavian countries were also reported by Middelboe et al.⁴⁶ In line with these findings, Giugiario et al³⁰ reported a competitive employment rate of 30% in people with schizophrenia treated in an outpatient setting in Italy. Comparable figures were reported for outpatients in Spain (25.9% respectively 27.2%).^23,56 Two studies were performed in Turkey.^37,57 In the study of Karadayi et al³⁷ employment was 37.3%. However, the employment rate, including students, reported by Uzun et al⁵⁷ was substantially lower (13.8%). This may partly be explained by the relatively older sample of the study population (median age 59 years).

HRQoL

In total, 12 studies were found that investigated the HRQoL of people with schizophrenia. Eight studies^{20,24,25,53,62–65} used a disease-specific HRQoL instrument: the Subjective Quality of Life (S-QoL) (one study), Heinrichs–Carpenter Quality of Life (QoL) scale (three studies), Lancaster Quality of Life Profile (two studies), and Lehman’s Quality of Life Interview (QOLI) (two studies). Just one of the studies a generic HRQoL instrument was applied the Wisconsin Quality of Life Index (W-QLI) scale,²⁵ and two studies applied a generic preference-based instrument (EQ-5D™ and Quality of Wellbeing).^20,64 In nine of the 12 studies, the relationship between employment and HRQoL was studied (Table 2). All but one of the studies found a positive relationship between being employed and HRQoL. In the study by Xie et al⁶⁰ which applied Lehman’s QOLI instrument, a nearly significant relationship (P=0.05) was established.

Table 2 Employment and health-related quality of life Abbreviations: CaW-QLI, the Wisconsin Quality of Life Index-Canadian version; HRQoL, health-related quality of life; NR, not reported; QLS, quality of life scale; QoL, quality of life; QOLI, quality of life interview; QWB, quality of wellbeing; S-QoL, subjective quality of life.

Discussion

Our review study showed that employment rates in people with schizophrenia vary between 4.5% and over 50%. There were significant differences between the definitions of employment that were applied in the studies. Nevertheless, unemployment figures are even more difficult to interpret, since these rates may refer to only those looking for work, while other rates may include respondents with long-term disability benefits or pensions. The comparison of employment rates between studies is further limited by differences in study designs, recruitment methods, diagnostic instruments, clinical variables reported, and different time frames for measuring employment. However, generally, employment in people with schizophrenia is relatively low, as was reported in the study of Marwaha et al.⁴² In that study, employment rates were presented for people with schizophrenia in the UK (12.9%), France (11.5%), and Germany (30.2%) in comparison with employment rates in the general population of these countries (of 71.0%, 62.2%, and 65.4%, respectively). Due to the methodological differences between the studies, we were unable to make a valid estimation of an average employment rate.

In addition to employment rates, we screened the papers on factors associated with employment, including the association of employment and HRQoL. The most frequently reported disease characteristics that were negatively associated with employment were negative symptoms and cognitive symptoms. This is in line with the earlier findings reported by of Marwaha and Johnson.³ Additionally, later age of disease onset, and the duration and continuous course of the disease may play a role in employment status of the person. Finally, employment rates were higher in people treated in an outpatient setting in comparison with rates among inpatients. It is not clear to what extent this finding is related to the severity of the disease. Both individual and environmental characteristics were found to be associated with employment rates. Individual characteristics associated with unemployment were (older) age, lower education, and sex (females). Additionally, employment rates were associated with a number of environmental factors. The large variation of employment rates between countries or regions seem to indicate that environmental characteristics, such as the availability of welfare benefits and the availability of vocational services and sheltered employment, may play an important role. Employment rates seem to be lower in countries with an increased level of social security, as was reported in the study of Thornicroft et al.⁵³ Relatively higher employment rates were generally found in studies performed in southern European countries. It can be assumed that these higher rates may be associated with dependence on the financial support of family members. These findings are in line with the study of Kilian and Becker, of the macroeconomic indicators of labor force participation of people with schizophrenia.⁶⁶ In addition, they found a close relation between general employment rates and employment rates of people with schizophrenia. In another study, a negative association was found between competitive employment and receipt of disability payment. Van der Wel et al reports that studies on the association of nonemployment among people with limiting longstanding illness and differences in welfare policies show equivocal results.⁶⁷ More research is recommended for assessing associations of welfare policy and employment in patients with severe mental illness.

Several studies suggested that the availability of vocational service factors may contribute to employment in people with schizophrenia. Increased access to rehabilitation services was associated with participation in both competitive and noncompetitive employment.⁶⁵

Generally, being employed and HRQoL were positively associated. A possible explanation for the association between being employed and HRQoL that was found in our review was indicated by Brekke et al⁶⁸ who described self-esteem to be a mediating factor between being employed and HRQoL. A larger social network due to being employed, resulting in a better HRQoL, is being proposed as another potential explanation.²⁵ Most studies applied a disease-specific HRQoL instrument. This seems in line with the current discussion about the validity of preference-based QoL instruments in people with schizophrenia. It is argued that generic preference-based instruments may not be appropriate for use in people with schizophrenia.⁶⁹

The conceptual model of Wilson and Cleary was a helpful tool to describe the different factors associated with employment and HRQoL.⁹ The model has been widely applied to different patient populations.⁹ In the current review we found studies that reported on associations between disease characteristics, individual characteristics and environmental characteristics and employment. Another important question relates to the association between employment and HRQol. That is, while employment may increase QoL, it is likely that those with higher QoL are more likely to be employed. Currently, there is little literature adequately assessing the causal relationship between these two domains, leading to a methodological gap in the literature. A limitation of our study is that we focused our literature search primarily on employment rates rather than on factors associated with employment. Consequently, we did not perform separate searches for factors associated with employment. However, due to the broad approach that was applied for reviewing the literature, the number of missing studies is assumed to be limited. Finally, we excluded studies on Individual Placement and Support and other vocational support programs, as our primary goal was to assess the general employment rate in people with schizophrenia. Supported employment programs are evidence-based practices to enhance people with mental health disability to return to work. Employment rates of persons with schizophrenia included in supported employment trials may differ due to specific in- and exclusion criteria.

In conclusion, our review showed a great variation in employment rates in people with schizophrenia. However, the overall employment rate was low. Employment rates varied widely across and within countries. Generally, there was a positive association between being employed and HRQoL. Importantly, however, the causal direction of this association remained unclear. When aiming to improve employment participation and associated HRQoL among people diagnosed with schizophrenia, symptoms, functional status, demographic characteristics of the population, and environmental factors should be taken into account. A better understanding of the interrelations of these components could lead to more integrated and personalized health management, and outcome optimization, for people with schizophrenia.

Acknowledgment

The study was financed through an unrestricted grant of F. Hoffmann-La Roche.

Disclosure

The authors report no conflicts of interest in this work.

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References

1.		Boardman J, Grove B, Perkins R, Shepherd G. Work and employment for people with psychiatric disabilities. Br J Psychiatry. 2003;182:467–468.
2.		Mangalore R, Knapp M. Cost of schizophrenia in England. J Ment Health Policy Econ. 2007;10(1):23–41.
3.		Marwaha S, Johnson S. Schizophrenia and employment – a review. Soc Psychiatry Psychiatr Epidemiol. 2004;39(5):337–349.
4.		Gladis MM, Gosch EA, Dishuk NM, Crits-Christoph P. Quality of life: expanding the scope of clinical significance. J Consult Clin Psychol. 1999;67(3):320–331.
5.		Priebe S, Warner R, Hubschmid T, Eckle I. Employment, attitudes toward work, and quality of life among people with schizophrenia in three countries. Schizophr Bull. 1998;24(3):469–477.
6.		Sullivan G, Wells KB, Leake B. Clinical factors associated with better quality of life in a seriously mentally ill population. Hosp Community Psychiatry. 1992;43(8):794–798.
7.		Lehman AF, Postrado LT, Rachuba LT. Convergent validation of quality of life assessments for persons with severe mental illnesses. Qual Life Res. 1993;2(5):327–333.
8.		Liberati A, Altman DG, Tetzlaff J, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. BMJ. 2009;339:b2700.
9.		Wilson IB, Cleary PD. Linking clinical variables with health-related quality of life. A conceptual model of patient outcomes. JAMA. 1995;273(1):59–65.
10.		Coons SJ, Rao S, Keininger DL, Hays RD. A comparative review of generic quality-of-life instruments. Pharmacoeconomics. 2000;17(1):13–35.
11.		van Os J, Kapur S. Schizophrenia. Lancet. 2009;374(9690):635–645.
12.		van Os J, Kenis G, Rutten BPF. The environment and schizophrenia. Nature. 2010;468(7321):203–212.
13.		Kay SR, Fiszbein A, Opler LA. The positive and negative syndrome scale (PANSS) for schizophrenia. Schizophr Bull. 1987;13(2):261–276.
14.		Dixon L. Dual diagnosis of substance abuse in schizophrenia: prevalence and impact on outcomes. Schizophr Res. 1999;35 Suppl:S93–S100.
15.		Westermeyer J. Comorbid schizophrenia and substance abuse: a review of epidemiology and course. Am J Addict. 2006;15(5):345–355.
16.		Carrà G, Johnson S, Bebbington P, et al. The lifetime and past-year prevalence of dual diagnosis in people with schizophrenia across Europe: findings from the European Schizophrenia Cohort (EuroSC). Eur Arch Psychiatry Clin Neurosci. 2012;262(7):607–616.
17.		Salyers MP, Mueser KT. Social functioning, psychopathology, and medication side effects in relation to substance use and abuse in schizophrenia. Schizophr Res. 2001;48(1):109–123.
18.		Chan S, Yu Iu W. Quality of life of clients with schizophrenia. J Adv Nurs. 2004;45(1):72–83.
19.		Abdel-Baki A, Lesage A, Nicole L, Cossette M, Salvat E, Lalonde P. Schizophrenia, an illness with bad outcome: myth or reality? Can J Psychiatry. 2011;56(2):92–101.
20.		Alonso J, Croudace T, Brown J, et al. Health-related quality of life (HRQL) and continuous antipsychotic treatment: 3-year results from the Schizophrenia Health Outcomes (SOHO) study. Value Health. 2009;12(4):536–543.
21.		Ascher-Svanum H, Zhu B, Faries D, Peng X, Kinon BJ, Tohen M. Tardive dyskinesia and the 3-year course of schizophrenia: results from a large, prospective, naturalistic study. J Clin Psychiatry. 2008;69(10):1580–1588.
22.		Barbui C, Kikkert M, Mazzi MA, et al. Comparison of patient and clinician perspectives in the assessment of antipsychotic medication adherence. Psychopathology. 2009;42(5):311–317.
23.		Bobes J, Arango C, Garcia-Garcia M, Rejas J; CLAMORS Study Collaborative Group. Prevalence of negative symptoms in outpatients with schizophrenia spectrum disorders treated with antipsychotics in routine clinical practice: findings from the CLAMORS study. J Clin Psychiatry. 2010;71(3):280–286.
24.		Boyer L, Aghababian V, Richieri R, et al. Insight into illness, neurocognition and quality of life in schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry. 2012;36(2):271–276.
25.		Caron J, Mercier C, Diaz P, Martin A. Socio-demographic and clinical predictors of quality of life in patients with schizophrenia or schizo-affective disorder. Psychiatry Res. 2005;137(3):203–213.
26.		Cechnicki A, Angermeyer MC, Bielańska A. Anticipated and experienced stigma among people with schizophrenia: its nature and correlates. Soc Psychiatry Psychiatr Epidemiol. 2011;46(7):643–650.
27.		Chwastiak LA, Rosenheck RA, McEvoy JP, Keefe RS, Swartz MS, Lieberman JA. Interrelationships of psychiatric symptom severity, medical comorbidity, and functioning in schizophrenia. Psychiatr Serv. 2006;57(8):1102–1109.
28.		Compton MT, Rudisch BE, Weiss PS, West JC, Kaslow NJ. Predictors of psychiatrist-reported treatment-compliance problems among patients in routine U.S. psychiatric care. Psychiatry Res. 2005;137(1–2):29–36.
29.		Cuyún Carter GB, Milton DR, Ascher-Svanum H, Faries DE. Sustained favorable long-term outcome in the treatment of schizophrenia: a 3-year prospective observational study. BMC Psychiatry. 2011;11:143.
30.		Giugiario M, Crivelli B, Mingrone C, et al. Cognitive function and competitive employment in schizophrenia: relative contribution of insight and psychopathology. Soc Psychiatry Psychiatr Epidemiol. 2012;47(4):553–561.
31.		Gureje O, Herrman H, Harvey C, Morgan V, Jablensky A. The Australian National Survey of Psychotic Disorders: profile of psychosocial disability and its risk factors. Psychol Med. 2002;32(4):639–647.
32.		Hansson L, Svensson B, Björkman T, et al. What works for whom in a computer-mediated communication intervention in community psychiatry? Moderators of outcome in a cluster randomized trial. Acta Psychiatr Scand. 2008;118(5):404–409.
33.		Henry LP, Amminger GP, Harris MG, et al. The EPPIC follow-up study of first-episode psychosis: longer-term clinical and functional outcome 7 years after index admission. J Clin Psychiatry. 2010;71(6):716–728.
34.		Hofer A, Bodner T, Kaufmann A, et al. Symptomatic remission and neurocognitive functioning in patients with schizophrenia. Psychol Med. 2011;41(10):2131–2139.
35.		Holthausen EA, Wiersma D, Cahn W, et al. Predictive value of cognition for different domains of outcome in recent-onset schizophrenia. Psychiatry Res. 2007;149(1–3):71–80.
36.		Honkonen T, Stengård E, Virtanen M, Salokangas RK. Employment predictors for discharged schizophrenia patients. Soc Psychiatry Psychiatr Epidemiol. 2007;42(5):372–380.
37.		Karadayi G, Emiroğlu B, Uçok A. Relationship of symptomatic remission with quality of life and functionality in patients with schizophrenia. Compr Psychiatry. 2011;52(6):701–707.
38.		Kulkarni J, de Castella AR, Filia KM, et al. Australian Schizophrenia Care and Assessment Programme: real-world schizophrenia: outcomes. Aust N Z J Psychiatry. 2007;41(12):969–979.
39.		Lambert M, Schimmelmann BG, Naber D, et al. Prediction of remission as a combination of symptomatic and functional remission and adequate subjective well-being in 2,960 patients with schizophrenia. J Clin Psychiatry. 2006;67(11):1690–1697.
40.		Mackell JA, Harrison DJ, McDonnell DD. Relationship between preventative physical health care and mental health in individuals with schizophrenia: a survey of caregivers. Ment Health Serv Res. 2005;7(4):225–228.
41.		Marwaha S, Johnson S, Bebbington PE, et al. Predictors of employment status change over 2 years in people with schizophrenia living in Europe. Epidemiol Psichiatr Soc. 2009;18(4):344–351.
42.		Marwaha S, Johnson S, Bebbington P, et al. Rates and correlates of employment in people with schizophrenia in the UK, France and Germany. Br J Psychiatry. 2007;191:30–37.
43.		Mausbach BT, Depp CA, Bowie CR, et al. Sensitivity and specificity of the UCSD Performance-based Skills Assessment (UPSA-B) for identifying functional milestones in schizophrenia. Schizophr Res. 2011;132(2–3):165–170.
44.		McCreadie RG; Scottish Comorbidity Study Group. Use of drugs, alcohol and tobacco by people with schizophrenia: case-control study. Br J Psychiatry. 2002;181:321–325.
45.		Mechanic D, Blider S, McAlpine DD. Employing persons with serious mental illness. Health Aff (Millwood). 2002;21(5):242–253.
46.		Middelboe T, Mackeprang T, Hansson L, et al. The Nordic Study on schizophrenic patients living in the community. Subjective needs and perceived help. Eur Psychiatry. 2001;16(4):207–214.
47.		Mueser KT, Salyers MP, Mueser PR. A prospective analysis of work in schizophrenia. Schizophr Bull. 2001;27(2):281–296.
48.		Ramsay CE, Stewart T, Compton MT. Unemployment among patients with newly diagnosed first-episode psychosis: prevalence and clinical correlates in a U.S. sample. Soc Psychiatry Psychiatr Epidemiol. 2012;47(5):797–803.
49.		Resnick SG, Rosenheck RA, Canive JM, et al. Employment outcomes in a randomized trial of second-generation antipsychotics and perphenazine in the treatment of individuals with schizophrenia. J Behav Health Serv Res. 2008;35(2):215–225.
50.		Rosen K, Garety P. Predicting recovery from schizophrenia: a retrospective comparison of characteristics at onset of people with single and multiple episodes. Schizophr Bull. 2005;31(3):735–750.
51.		Slade E, Salkever D. Symptom effects on employment in a structural model of mental illness and treatment: analysis of patients with schizophrenia. J Ment Health Policy Econ. 2001;4(1):25–34.
52.		Spellmann I, Riedel M, Schennach R, et al. One-year functional outcomes of naturalistically treated patients with schizophrenia. Psychiatry Res. 2012;198(3):378–385.
53.		Thornicroft G, Tansella M, Becker T, et al; EPSILON Study Group. The personal impact of schizophrenia in Europe. Schizophr Res. 2004;69(2–3):125–132.
54.		Thorup A, Petersen L, Jeppesen P, et al. Gender differences in young adults with first-episode schizophrenia spectrum disorders at baseline in the Danish OPUS study. J Nerv Ment Dis. 2007;195(5):396–405.
55.		Üçok A, Gorwood P, Karadayi G; EGOFORS. Employment and its relationship with functionality and quality of life in patients with schizophrenia: EGOFORS Study. Eur Psychiatry. 2012;27(6):422–425.
56.		Usall J, Araya S, Ochoa S, Busquets E, Gost A, Márquez M; Assessment Research Group in Schizophrenia (NEDES). Gender differences in a sample of schizophrenic outpatients. Compr Psychiatry. 2001;42(4):301–305.
57.		Uzun O, Cansever A, Basoğlu C, Ozşahin A. Smoking and substance abuse in outpatients with schizophrenia: a 2-year follow-up study in Turkey. Drug Alcohol Depend. 2003;70(2):187–192.
58.		Waghorn G, Chant D, Jaeger J. Employment functioning and disability among community residents with bipolar affective disorder: results from an Australian community survey. Bipolar Disord. 2007;9(1–2):166–182.
59.		West JC, Wilk JE, Olfson M, et al. Patterns and quality of treatment for patients with schizophrenia in routine psychiatric practice. Psychiatr Serv. 2005;56(3):283–291.
60.		Xie H, McHugo GJ, Helmstetter BS, Drake RE. Three-year recovery outcomes for long-term patients with co-occurring schizophrenic and substance use disorders. Schizophr Res. 2005;75(2–3):337–348.
61.		Ye W, Fujikoshi S, Nakahara N, Takahashi M, Ascher-Svanum H, Ohmori T. Improved outcomes following a switch to olanzapine treatment from risperidone treatment in a 1-year naturalistic study of schizophrenia patients in Japan. Psychiatry Clin Neurosci. 2012;66(4):313–321.
62.		Eklund M, Hansson L, Bejerholm U. Relationships between satisfaction with occupational factors and health-related variables in schizophrenia outpatients. Soc Psychiatry Psychiatr Epidemiol. 2001;36(2):79–83.
63.		Marwaha S, Johnson S, Bebbington P, et al; EuroSC Study Group. Correlates of subjective quality of life in people with schizophrenia: findings from the EuroSC study. J Nerv Ment Dis. 2008;196(2):87–94.
64.		Palmer BW, Heaton RK, Gladsjo JA, et al. Heterogeneity in functional status among older outpatients with schizophrenia: employment history, living situation, and driving. Schizophr Res. 2002;55(3):205–215.
65.		Rosenheck R, Leslie D, Keefe R, et al; CATIE Study Investigators Group. Barriers to employment for people with schizophrenia. Am J Psychiatry. 2006;163(3):411–417.
66.		Kilian R, Becker T. Macro-economic indicators and labour force participation of people with schizophrenia. J Ment Health. 2007;16(2):211–222.
67.		van der Wel KA, Dahl E, Thielen K. Social inequalities in ‘sickness’: European welfare states and non-employment among the chronically ill. Soc Sci Med. 2011;73(11):1608–1617.
68.		Brekke JS, Levin S, Wolkon GH, Sobel E, Slade E. Psychosocial functioning and subjective experience in schizophrenia. Schizophr Bull. 1993;19(3):599–608.
69.		Papaioannou D, Brazier J, Parry G. How valid and responsive are generic health status measures, such as EQ-5D and SF-36, in schizophrenia? A systematic review. Value Health. 2011;14(6):907–920.

Supplementary material

(“schizophrenia”[MeSH Terms]

OR “schizophrenia”[All Fields])

and

(“employment”[MeSH Terms]

OR “employment”[All Fields])

OR (“unemployment”[MeSH Terms]

OR “unemployment”[All Fields])

OR (paid[All Fields]

and

(“work”[MeSH Terms]

OR “work”[All Fields]))

OR ((“work”[MeSH Terms]

OR “work”[All Fields])

and

capacity[All Fields])

OR (“efficiency”[MeSH Terms]

OR “efficiency”[All Fields]

OR “productivity”[All Fields])

OR (“absenteeism”[MeSH Terms]

OR “absenteeism”[All Fields])

OR “presenteeism”[All Fields]

OR (“occupations”[MeSH Terms]

OR “occupations”[All Fields]

OR “occupation”[All Fields])

and

((hasabstract[text]

and

“loattrfull text”[sb])

and

(“2000/01/01”[PDAT] : “2013/12/31”[PDAT])

and

“humans”[MeSH Terms]

and

English[lang]

and

“adult”[MeSH Terms])