Abstract
Objective
The objective of this survey was to assess patient outcomes and caregiver status by disease severity among patients with schizophrenia in the United States.
Methods
A point-in-time survey was conducted between July and October 2019 via the Adelphi Schizophrenia Disease Specific Programme. Psychiatrists reported on their next 10 eligible patients with schizophrenia including demographics, disease severity, treatment history and hospitalizations. Patients receiving treatment for schizophrenia were classified as mild, moderate or severe based on disease severity. Regression models adjusted for age, sex and race/ethnicity.
Results
Psychiatrists (n = 124) reported on 435 mild, 401 moderate and 247 severe patients. Greater severity of schizophrenia was associated with a greater number of hospitalizations related to schizophrenia relapse in the previous 12 months (moderate vs. mild: adjusted incidence rate ratio (aIRR) [95% CI] = 2.17 [1.60–2.94]; severe vs. mild: aIRR = 5.45 [3.59–8.27]), lower full-time employment (moderate vs. mild: adjusted odds ratio (aOR) = 0.15 [0.08–0.28]; severe vs. mild: aOR = 0.02 [0.002–0.12]) and greater unemployment due to disability (moderate vs. mild: aOR = 4.24 [3.02–5.97]; severe vs. mild: aOR = 10.85 [6.85–17.17]). Patients with severe vs. mild schizophrenia had lower average quality of life (QoL) measured by the EuroQoL 5-dimension Health Index (difference = −0.16 [−0.23−0.09]). Among patients requiring care, patients with severe vs. mild schizophrenia received more caregiver hours per week (aIRR = 1.89 [1.25–2.84]).
Conclusions
Greater severity of schizophrenia was associated with a significantly greater number of hospitalizations and greater unemployment due to disability. Compared with mild schizophrenia, severe schizophrenia was associated with worse patient QoL and greater caregiver hours.
Introduction
Schizophrenia is a severe mental illness that may result in hallucinations, delusions and extremely disordered thinking, leading to impaired functioning and lifelong treatmentCitation1. Due to its debilitating nature, schizophrenia is one of the top 20 leading causes of disability worldwideCitation2. The mean lifetime prevalence of schizophrenia is 1.1% in the USCitation3. Despite the low overall prevalence, the economic burden of schizophrenia is high (annual cost >$280 billion) driven by productivity loss due to caregiving, unemployment and direct healthcare costsCitation4,Citation5.
Many disease-related factors contribute to the high costs associated with schizophrenia. Relapse among patients with schizophrenia is common with up to 40–79% of patients relapsing within one year of hospital dischargeCitation6,Citation7. Patients with schizophrenia also experience greater morbidity and mortality associated with comorbidities (e.g. obesity, diabetes, hyperlipidemia, substance abuse disorder), smoking and difficulty accessing healthcareCitation8. Patients with schizophrenia have a reduced life expectancy, on average, of approximately 15 yearsCitation9. Additionally, a large proportion (41%) of patients with schizophrenia live with caregivers, who may also experience emotional, physical and financial distressCitation10.
The burden of schizophrenia, both direct and indirect, varies by stage of illness (early vs. chronic)Citation11 and disease symptomsCitation12. Systematic literature reviews have reported that patients with severe vs. mild schizophrenia may have greater healthcare resource utilization (HCRU), lower employment and worse quality of life (QoL)Citation13–15. However, US-specific data are needed due to country-specific support systems that may impact patients with schizophrenia and their caregivers such as access to behavioral health resources and social security benefits. Employment rates, in particular, have been shown to be associated with country-specific social welfare policiesCitation16. The objective of this survey was to assess the association between schizophrenia disease severity and patient outcomes (HCRU, housing circumstances, employment status, work impairment and QoL) and caregiver status (care required and hours per week of caregiving required) and to report real-world estimates of patient outcomes and caregiver status in the US.
Methods
Data source
Data were collected in the US using the Adelphi Schizophrenia Disease Specific Programme (DSP) conducted between July and October 2019. The DSP is a point-in-time survey of physicians and their consulting patients presenting in a real-world clinical setting. The DSP used a convenience sample of psychiatrists without quotas by setting (i.e. private practice, general hospitals, VA hospitals, state hospitals). Psychiatrists were recruited by field-based interviewers from a US specialist recruitment agency, which has developed a database from publicly available lists and through targeted recruitment. A complete description of the survey methods has been published previouslyCitation17.
A geographically diverse sample of psychiatrists was recruited; physicians were eligible to participate in the survey if they were personally responsible for treatment decisions and management of patients with schizophrenia. Psychiatrists completed a physician-reported patient record form for their next 10 consecutive eligible consulting patients (8 outpatients and 2 inpatients, where possible). A quota of 8 outpatients and 2 inpatients was set for each physician to ensure an adequate range of disease severity. Patients were eligible for inclusion if they were adults (age ≥18 years old) and had a physician-confirmed diagnosis of schizophrenia. Physician-reported patient record forms included details on patients’ schizophrenia disease severity, demographics, clinical characteristics, employment status, housing circumstances, HCRU in the last 12 months, hospitalizations since diagnosis, whether a caregiver was required and number of hours of caregiving required per week. Physician-reported patient record forms were completed based on patient records and history available to the physician as well as the judgement and diagnostic skills of the physician, which is consistent with how decisions are made in routine clinical practice. Caregivers could also be present at consultations for severely ill patients. The number of hours of caregiving per week was an estimate or provided by caregiver if present.
Patients for whom a patient record form was completed were then asked to complete a patient self-completion questionnaire on a voluntary basis. Patients that completed a patient self-completion questionnaire provided informed consent. Patient self-completion questionnaires asked about productivity and QoL, were completed by the patient independently from their physician and were returned in a sealed envelope to ensure that patients’ responses were confidential from their physician. Patients who were not currently receiving treatment for schizophrenia were excluded from the analysis.
Disease severity
The Clinical Global Impression Severity (CGI-S) Scale was used to assess schizophrenia severity and was based on observed and reported severity of illness at the time of assessmentCitation18. Physician-reported CGI-S is scored on a scale of 1–7 with higher scores indicating greater disease severityCitation19. The CGI-S score was used to stratify patients by disease severity to mild (1 = normal, not at all ill; 2 = borderline mentally ill; 3 = mildly ill), moderate (4 = moderately ill) and severe (5 = markedly ill; 6 = severely ill; 7 = among the most extremely ill patients) schizophrenia groups. Mild, moderate and severe categories based on physician-reported CGI-S scores have been used in previous analyses of the Adelphi Schizophrenia DSPCitation20.
Patient outcomes and caregiver status
The primary outcome was HCRU related to schizophrenia relapse. Hospitalizations were reported in the previous 12 months and since diagnosis. Additional HCRU outcomes in the previous 12 months included healthcare practitioner (HCP) visits, hospital admissions through the emergency room (ER) and hospital length of stay. Location of HCP visits were not specified by the survey and, therefore, were based on physician judgement.
Secondary outcomes included housing circumstances, employment status, work and activity impairment, quality of life and caregiver status. Housing circumstances were physician reported and included living alone, living with a partner/spouse, living with relatives/friends/others, living in supported housing or living in a homeless shelter. The psychiatrist reported on a patient’s employment status and reason for not working. The reported outcomes included being in full-time employment, part-time employment, a student/homemaker/retired, unemployed due to disability, unemployed for other reason and on sick leave. Additional physician-reported outcomes included the proportion of patients requiring a caregiver and hours of care per week.
The patient-reported Work Productivity and Activity Impairment (WPAI) questionnaire (scale of 0–100 with a higher score indicating greater impairment) was used to assess overall work and activity impairment in the past weekCitation21. Patient QoL was measured using the EuroQoL 5-dimension (EQ-5D) Health Index (scale 0–1 with a higher score indicating better health state) and Visual Analogue Scale (VAS; scale of 0–100 with a higher score indicating better health state)Citation22,Citation23. Patient QoL was also measured with the Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form (Q-LES-Q-SF; scale of 0–100 with a higher score indicating better QoL)Citation24.
Other variables
Patient demographics included age, sex, race/ethnicity, highest level of education, health insurance type and treatment setting. Patient clinical characteristics included body mass index (BMI); cardiometabolic comorbidities such as diabetes, dyslipidemia, hypertension and obesity; and psychiatric comorbidities such as anxiety, alcohol use disorder, depression, insomnia and substance use disorder.
Statistical analysis
Descriptive statistics were reported for continuous (mean and standard deviation) and categorical variables (counts and proportions). Comparisons between schizophrenia severity groups were conducted using analysis of variance for continuous variables and chi-squared tests for categorical variables. Missing data were not imputed. Observations with missing values were only excluded from analyses of the variable with missing data. Regression analyses adjusted for age, sex and race/ethnicity by including age, sex and race/ethnicity as independent variables. Other clinical characteristics were not controlled for because they are manifestations of the same underlying concept being measured by overall disease severity. The adjusted analyses provided a real-world estimate of the patient outcomes and caregiver status. Multicollinearity in the regression models was checked for by examining the variance inflation factors and the condition number. No issues with multicollinearity were observed.
Choice of regression methods were based on the type of dependent variable. Linear regressions were used for each of the continuous outcomes including EQ-5D, Q-LES-Q-SF and WPAI scores as well as caregiver hours. Logistic regressions were used for binary outcomes including any hospitalizations, employment status, housing circumstances and caregiver required. Negative binomial regressions were used for HCRU outcomes expressed as counts including number of HCP visits, hospitalizations, hospital admissions through the ER and number of days hospitalized. Standard errors were clustered by psychiatrist. Adjusted odds ratios (aORs) and adjusted incidence rate ratios (aIRRs) were reported for logistic and negative binomial regressions, respectively. Average margin estimates and 95% confidence intervals (CIs) were reported for adjusted means and proportions. All analyses were conducted using Stata v17 (StataCorp LLC, College Station, TX). Statistical significance was set at p <.05.
Ethical considerations
Data collection was conducted in line with European Pharmaceutical Marketing Research Association guidelinesCitation25. The survey obtained ethics approval from the Western Institutional Review Board (AG8618). Each survey was performed in full accordance with the US Health Insurance Portability and Accountability Act 1996Citation26, and Health Information Technology for Economic and Clinical Health Act legislationCitation27. Physician participation was financially incentivized with reimbursement upon survey completion according to fair market research rates. Patients were not compensated for participation.
Results
Patient characteristics
Psychiatrists (N = 124/1470 contacted, response rate = 8.4%) were geographically distributed across the US (Midwest = 41.9%, West = 23.4%, Northeast = 20.2% and South = 14.5%). Psychiatrists collected data for 435 (40.2%), 401 (37.0%) and 247 (22.8%) eligible patients with mild, moderate and severe schizophrenia, respectively (). Among those patients, 217 (49.9%), 200 (49.9%) and 89 (36.0%) patients with mild, moderate and severe schizophrenia, respectively, completed a patient self-completion questionnaire. Patient demographics and clinical characteristics for patients with a patient record form are presented in .
Figure 1. Flow diagram.
Table 1. Patient demographics and clinical characteristics.
Patients were, on average, 40 years old. Over half of patients were White (60.7%), male (58.4%) and treated in an outpatient setting (82.2%). Most patients had at least a high school education (81.6%). Anxiety (28.3%) was the most prevalent comorbidity followed by hypertension (23.6%), dyslipidemia (18.3%), obesity (17.5%) and depression (14.3%). A greater proportion of patients who completed the patient self-completion questionnaire were White (64.8 vs. 57.0%, p = .030) and had at least a high school education (87.1 vs. 76.8%, p < .001), and a lower proportion had severe schizophrenia (17.6 vs. 27.4%, p < .001) (Online Appendix Table A1). Unadjusted patient outcomes and caregiver status are reported in the supplementary materials (Online Appendix Table A2, Table A3 and Table A4).
Adjusted physician-reported patient outcomes
shows the adjusted means and proportions for physician-reported patient outcomes. Adjusted ratios for physician-reported patient outcomes are presented in (HCRU) and 3 (employment status and housing circumstances). The outcome-specific sample sizes from also apply to and .
Figure 2. Adjusted HCRU related to schizophrenia relapse (physician reported). Abbreviations. CI, Confidence interval; ER, Emergency room; HCP, Healthcare practitioner; HCRU, Healthcare resource utilization; IRR, Incidence rate ratio; OR, Odds ratio; ref, Reference. Bold text indicates statistical significance vs. mild severity based on 95% CI. Outcomes were adjusted for patient age, sex and race/ethnicity.
Figure 3. Adjusted employment status and housing circumstances (physician reported). Abbreviations. CI, Confidence interval; OR, Odds ratio; ref, Reference. aUpper limit of adjusted OR not shown on x-axis but reported in list of adjusted OR. Bold text indicates statistical significance vs. mild severity based on 95% CI. Outcomes were adjusted for patient age, sex and race/ethnicity.
Table 2. Adjusted physician-reported patient outcomes.
The average number of hospitalizations related to schizophrenia relapse in the previous 12 months was significantly lower in patients with mild schizophrenia (average margin estimate [95% CI] = 0.2 [0.2–0.3]) compared to patients with moderate (0.5 [0.4–0.6], aIRR [95% CI] = 2.17 [1.60–2.94]) and severe (1.3 [0.9–1.7], aIRR = 5.45 [3.59–8.27]) disease. Average inpatient days were also lower in patients with mild schizophrenia (1.9 [0.5–3.2]) compared to patients with moderate (3.9 [2.6–5.1], aIRR = 2.61 [1.41–4.82]) and severe (9.9 [5.5–14.2], aIRR = 6.33 [3.57–11.23]) disease. Patients with mild schizophrenia also had a lower average number of hospital admissions through the ER (0.2 [0.1–0.2]) compared to patients with moderate (0.4 [0.3–0.6], aIRR = 2.07 [1.03–4.13]) and severe (1.0 [0.8–1.2], aIRR = 5.29 [2.56–10.94]) disease. Average hospitalizations since schizophrenia diagnosis were also lower in patients with mild schizophrenia (1.1 [0.7–1.5]) compared to patients with moderate (2.4 [1.5–3.3], aIRR = 2.11 [1.45–3.05]) or severe (5.4 [3.2–7.7], aIRR = 4.80 [2.91–7.91]) disease.
Patients with mild schizophrenia were significantly more likely to live with a partner or spouse (28.0% [22.5–33.4%]) compared to patients with moderate (17.3% [13.2–21.4%], aOR = 0.54 [0.37–0.78]) or severe (8.8% [4.5–13.0%], aOR = 0.25 [0.13–0.46]) disease. Additionally, patients with mild schizophrenia were less likely to live in supported housing (mild = 4.4% [2.1–6.7%] vs. moderate = 11.7% [7.5–15.8%], aOR = 2.85 [1.64–4.96]; vs. severe = 16.4% [11.2–21.6%], aOR = 4.24 [2.34–7.70]) or in a homeless shelter (mild = 1.2% [0.2–2.2%] vs. moderate = 3.0% [1.3–4.8%], aOR = 2.63 [1.09–6.36]; vs. severe = 7.9% [4.2–11.7%], aOR = 7.25 [3.03–17.31]) compared to patients with greater disease severity.
The proportion of patients in full-time employment was significantly greater in patients with mild schizophrenia (19.1% [14.0–24.3%]) than patients with moderate (3.4% [1.6–5.1%], aOR = 0.15 [0.08–0.28]) or severe (0.4% [−0.4–1.2%], aOR = 0.02 [0.002–0.12]) disease. Patients with mild schizophrenia (20.1% [15.4–24.9%]) were less likely to be unemployed due to disability compared to patients with moderate (51.7% [44.7–58.6%], aOR = 4.24 [3.02–5.97]) and severe (73.2% [65.8–80.6%], aOR = 10.85 [6.85–17.17]) disease.
Adjusted patient-reported patient outcomes
shows the adjusted means and proportions for patient-reported outcomes. Adjusted differences for patient-reported outcomes are presented in . Greater severity of schizophrenia was associated with significantly greater patient-reported work (average WPAI overall work score: mild = 27.7 [23.9–31.5] vs. moderate = 39.2 [30.9–47.5], difference = 11.5 [3.5–19.5]; vs. severe = 52.1 [30.6–73.6], difference = 24.4 [3.1–45.7]) and activity (average WPAI overall activity score: mild = 32.7 [29.1–36.4] vs. moderate = 49.9 [45.2–54.6], difference = 17.2 [12.0–22.4]; vs. severe = 63.5 [55.1–71.8], difference = 30.8 [21.9–39.6]) impairment.
Figure 4. Adjusted patient work and activity impairment and QoL outcomes (patient reported). Abbreviations. CI, Confidence interval; diff, Difference; EQ-5D, EuroQoL 5-dimension; HI, Health index; Q-LES-Q-SF, Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form; QoL, Quality of life; VAS, Visual analogue scale; WPAI, Work Productivity and Activity Impairment questionnaire. *Significant vs. mild severity at p < .05. Outcomes were adjusted for patient age, sex and race/ethnicity.
Table 3. Adjusted patient-reported outcomes.
Compared to patients with mild schizophrenia, patients with severe schizophrenia reported significantly lower average QoL (EQ-5D Health Index: mild = 0.81 [0.77–0.85] vs. severe = 0.65 [0.58–0.73], difference = −0.16 [−0.23–−0.09]; EQ-5D VAS: mild = 76.2 [73.3–79.2] vs. severe = 61.2 [53.5–68.9], difference= −15.0 [−23.4–−6.6]) and life satisfaction (Q-LES-Q-SF: mild = 56.5 [52.6–60.4] vs. severe = 40.3 [34.7–45.9], difference = −16.2 [−22.8–−9.6]).
Adjusted caregiver status
Compared to patients with mild disease (12.7% [8.6–16.8%]), a greater proportion of patients with moderate (35.7% [28.8–42.5%], aOR = 3.82 [2.51–5.80]) and severe (50.0% [40.6–59.4%], aOR = 6.89 [4.29–11.07]) schizophrenia were reported by their psychiatrist as requiring a caregiver (). Among patients who required a caregiver, patients with mild schizophrenia required, on average, 25.0 [17.7–32.2] hours of care per week compared to 32.1 [23.7–40.5] hours of care (aIRR = 1.29 [0.98–1.69]) and 47.1 [32.0–62.2] hours of care (aIRR = 1.89 [1.25–2.84]) in patients with moderate and severe disease, respectively.
Table 4. Adjusted patients’ caregiver status.
Discussion
This study adds to the literature by providing point-in-time estimates of HCRU, housing circumstances, employment status, work impairment and QoL as well as caregiver status by schizophrenia disease severity for patients in the US. Greater severity of schizophrenia was associated with worse patient outcomes and greater caregiver burden among patients receiving treatment for schizophrenia. Patients with both moderate and severe schizophrenia had greater HCRU related to schizophrenia relapse as well as higher rates of living in supported housing or a homeless shelter and being unemployed due to disability. Patients with severe schizophrenia also had significantly lower QoL and required greater number of caregiver hours compared to patients with mild disease.
Differences in HCRU by disease severity were consistent with those reported in a study of secondary psychiatric services in Europe (France, Germany and the United Kingdom)Citation28. Based on an eight-level summary of Positive and Negative Syndrome Scale scores, the European study reported a greater proportion of patients with any hospital visits over 6 months (mild = 11% vs. extremely severe = 35%) and greater average hospital days over 6 months (mild = 4.29 vs. extremely severe = 18.17 days) in patients with the highest versus lowest level of schizophrenia symptomsCitation28. We found that the adjusted proportion of patients hospitalized and average number of hospital days followed a similar pattern (i.e. greater HCRU in patients with severe vs. mild schizophrenia). The level of adjusted average hospitalizations in our study were similar to a different US study of patients with schizophrenia with 12 month follow-upCitation29. The difference in days hospitalized between the mentioned US and European studies could be due to analysis design, disease severity definitions or differences in the countries’ healthcare systems.
Unemployment among patients with schizophrenia makes up a large proportion (38%) of indirect economic burden of schizophrenia in the USCitation4. Employment rates among patients with schizophrenia may be as low as 10–20%Citation30. Those rates are consistent with the moderate and severe schizophrenia groups in our survey. Adjusted employment (combining both full- and part-time averages) rates were 23.1% and 6.2% in patients with moderate and severe schizophrenia, respectively (). However, almost 50% of patients with mild schizophrenia were employed in our survey. Our results suggest that the burden of schizophrenia due to unemployment is greater in patients with moderate and severe compared to mild disease.
Utilities are a measure of health related QoL that range from 0 (death) to 1 (full health). In the existing literature, health state utility values among patients with schizophrenia have been shown to vary by relapse-related health states (stable: 0.650–0.919; relapse requiring hospitalization: 0.270–0.604; relapse not requiring hospitalization:0.460–0.762; relapse only: 0.498–0.700)Citation14 and across the symptom severity spectrum (mild: 0.79 [95% CI = 0.70–0.88]; moderate: 0.69 [95% CI = 0.54–0.85]; severe: 0.34 [95% CI = 0.13–0.56])Citation15. The EQ-5D Health Index average scores from our survey were on the upper end of the ranges reported by other studies, which was consistent with using EQ-5D for utility measurement in the schizophrenia populationCitation15.
A literature review on the humanistic burden of schizophrenia reported that 19% of caregivers for patients with schizophrenia in the US provide more than 40 h of care per weekCitation10. Our findings are consistent with the high level of caregiver support required, particularly when caring for patients with moderate or severe disease. Greater care requirements increase the economic burden of schizophrenia for both patients and caregivers.
A disproportionate amount of the high burden of schizophrenia is driven by patients with severe disease. Patients with severe schizophrenia have greater HCRU, less stable housing circumstances, lower employment, lower QoL and need more caregiver hours. Evaluation of response to schizophrenia treatment should include the assessment of these patient outcomes in addition to symptoms. Further, interventions should be designed to focus on patients with severe schizophrenia to lower HCRU and improve patient outcomes.
This survey is subject to several limitations common to the Adelphi DSP. Firstly, psychiatrists and patients were not randomly selected for participation in the patient record form component of the survey. While minimal inclusion criteria governed the selection of participating physicians, participation was influenced by their willingness to complete the survey. Psychiatrists reported on their next 10 consecutive patients to limit patient pre-selection and to obtain a representative sample of the psychiatrists’ patients. However, no procedure was in place to verify this. Additionally, patients that visited the psychiatrist more frequently were more likely to be selected. Therefore, the results of the physician-reported outcomes may not reflect the general population of patients with schizophrenia including those with more recent onset schizophrenia or located in a different geographic area. Secondly, participation in the patient self-completion questionnaire was voluntary and influenced by patients’ willingness and/or ability to complete the survey. The patient self-completion questionnaire response rate was 50%, 50% and 36% in patients with mild, moderate and severe disease, respectively. It is unclear how the missing patient self-completion questionnaires and lower response rate in patients with severe schizophrenia affected the results. Significant differences in the sample with and without patient self-completion questionnaires may further reduce the generalizability of the patient-reported outcomes. However, the significant results when comparing severe to mild schizophrenia patients were potentially conservative estimates if fewer of the most severe patients completed the survey. The samples were also deemed statistically robust. Thirdly, physician- and patient-reported survey data may have been subject to poor recall. To limit this, physicians reported from patient medical records, and patients were only asked to recall the last 7 days. Fourthly, the sample size varies due to missing data in the analysis of each outcome. While the survey results are broadly comparable, there is no complete case analysis or consistent sample. The response rate is over 80% for most outcomes reported on the physician-reported patient record form with exception being number of hospitalizations since diagnosis, which could be missing due to incomplete medical history since diagnosis. The response rate for patient self-completion questionnaire outcomes was less than 40% for WPAI overall work impairment, which is due in part to patients not being in work. Fifthly, schizophrenia diagnosis was not confirmed as part of the survey. It is possible that some patients were misdiagnosed with schizophrenia. Additionally, psychiatrists reported on their own patients, so we were unable to check for inter-rater reliability. Finally, the relationship between schizophrenia disease severity, other clinical variables such as cardiometabolic and psychiatric comorbidities and outcomes such as employment status and QoL is complex. The point-in-time design of this survey could not establish a causal relationship or the timing between disease severity changes and outcomes. However, the association between schizophrenia disease severity and the reported outcomes could be established.
Conclusions
The burden of schizophrenia is significantly greater for patients and caregivers of patients with greater disease severity, which was associated with a significantly higher number of hospitalizations and greater level of work and activity impairment. Patients with severe compared with mild schizophrenia had lower QoL and required more hours of care per week. Patients with severe schizophrenia may benefit from an assessment of patient outcomes in addition to symptoms to evaluate response to schizophrenia treatment. Future clinical research should focus on reducing the burden of schizophrenia in patients with more severe disease.
Transparency
Declaration of funding
The survey data reported on in this manuscript is from the Adelphi Schizophrenia Disease Specific Programme to which Sunovion subscribed.
Declaration of financial/other relationships
A.K., Q.F., C.D. and G.R.W. have disclosed that they are employees of Sunovion. J.S., H.B. and C.W. have disclosed that they are employees of Adelphi Real World. CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.
Author contributions
All authors were directly involved in the analysis of the survey data, interpretation of results, drafting of the manuscript and providing final review.
Previous presentation
An earlier version of this work was presented as a poster at the 2021 Congress of the Schizophrenia International Research Society; 2021 Apr 17-21; virtual conference.
CMRO_Appendix_FINAL.docx
Download MS Word (64 KB)Acknowledgements
The authors thank Barbara Blaylock from Blaylock Health Economics LLC for providing medical writing support.
Data availability statement
Data collection was undertaken by Adelphi Real World as part of an independent survey, entitled the Adelphi Schizophrenia Disease Specific Programme, subscribed to by multiple pharmaceutical companies of which one was Sunovion. Sunovion did not influence the original survey through either contribution to the design of questionnaires or data collection. All data that support the findings of this survey are the intellectual property of Adelphi Real World.
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