Background and objective
Participants experiencing homelessness and mental illness who received housing and support through the At Home/Chez Soi trial showed modest gains in quality of life (QOL) compared to treatment as usual participants. Participants’ QOL ratings over time may have been affected by either response shift triggered by new life circumstances or by random variation in the meaning of QOL ratings. This study seeks to identify both phenomena to estimate the intervention’s effect on true change in QOL.
Using the residuals from a regression model of the global item of Lehman’s 20-item quality of life interview (QOLI-20), latent trajectory analysis was used to identify response shift, while a measure of overall variability in residuals identified random variation of QOL. The latter was used to adjust group comparisons of QOLI-20 total scores and the global item.
Equivalent distributions of both groups’ participants across latent trajectory classes (χ2 = 2.97, p = .397) suggest that the intervention did not trigger response shift. However, random variation interacted significantly with the treatment effect on global item ratings. For every increase of one standard deviation of residuals, treatment odds ratios decreased by a factor of 0.70 (SE 1.18, p = .036, 95% CI 0.50–0.98).
Measuring random variation in QOL ratings from the standard deviation of residuals offers the ability to approximate, although indirectly, how participants’ QOL is truly affected by a housing intervention. Specifically, we found that QOL improvement is more evident when QOL ratings have a consistent meaning over time.
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Sprangers, M. A., & Schwartz, C. E. (1999). Integrating response shift into health-related quality of life research: A theoretical model. Social Science and Medicine (1982), 48(11), 1507–1515.
Mayo, N. E., Scott, S. C., Dendukuri, N., Ahmed, S., & Wood-Dauphinee, S. (2008). Identifying response shift statistically at the individual level. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 17(4), 627–639. doi:10.1007/s11136-008-9329-2.
Schwartz, C. E., Bode, R., Repucci, N., Becker, J., Sprangers, M. A. G., & Fayers, P. M. (2006). The clinical significance of adaptation to changing health: A meta-analysis of response shift. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 15(9), 1533–1550. doi:10.1007/s11136-006-0025-9.
Schwartz, C. E., Merriman, M. P., Reed, G. W., & Hammes, B. J. (2004). Measuring patient treatment preferences in end-of-life care research: Applications for advance care planning interventions and response shift research. Journal of Palliative Medicine, 7(2), 233–245. doi:10.1089/109662104773709350.
Rapkin, B. D., & Schwartz, C. E. (2004). Toward a theoretical model of quality-of-life appraisal: Implications of findings from studies of response shift. Health and Quality of Life Outcomes, 2, 14. doi:10.1186/1477-7525-2-14.
Schwartz, C. E., & Rapkin, B. D. (2004). Reconsidering the psychometrics of quality of life assessment in light of response shift and appraisal. Health and Quality of Life Outcomes, 2, 16. doi:10.1186/1477-7525-2-16.
Goering, P. N., Streiner, D. L., Adair, C., Aubry, T., Barker, J., Distasio, J., … Zabkiewicz, D. M. (2011). The At Home/Chez Soi trial protocol: A pragmatic, multi-site, randomised controlled trial of a Housing First intervention for homeless individuals with mental illness in five Canadian cities. BMJ Open, 1(2), e000323–e000323. doi:10.1136/bmjopen-2011-000323.
Goering, P., Veldhuizen, S., Watson, A., Adair, C. E., Kopp, B. C., Latimer, E., … Aubry, T. (2014). National At Home/Chez Soi Final Report. Calgary, AB: Mental Health Commission of Canada. Retrieved from http://www.mentalhealthcommission.ca.
Atkinson, M., Zibin, S., Chuang, H., & others (1997). Characterizing quality of life among patients with chronic mental illness: A critical examination of the self-report methodology. American Journal of Psychiatry, 154(1), 99–105.
Ahmed, S., Mayo, N., Scott, S., Kuspinar, A., & Schwartz, C. (2011). Using latent trajectory analysis of residuals to detect response shift in general health among patients with multiple sclerosis. [corrected]. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 20(10), 1555–1560. doi:10.1007/s11136-011-0005-6.
Mayo, N. E., Scott, S. C., & Ahmed, S. (2009). Case management poststroke did not induce response shift: The value of residuals. Journal of Clinical Epidemiology, 62(11), 1148–1156. doi:10.1016/j.jclinepi.2009.03.020.
Mayo, N. E., Scott, S. C., Bernstein, C. N., & Lix, L. M. (2015). How are you? Do people with inflammatory bowel disease experience response shift on this question? Health and Quality of Life Outcomes, 13(1), 52. doi:10.1186/s12955-015-0232-6.
Stergiopoulos, V., Hwang, S. W., Gozdzik, A., Nisenbaum, R., Latimer, E., Rabouin, D., Goering, P. N. (2015). Effect of scattered-site housing using rent supplements and intensive case management on housing stability among homeless adults with mental illness: A Randomized Trial. JAMA: The Journal of The American Medical Association, 313(9), 905. doi:10.1001/jama.2015.1163.
Aubry, T., Goering, P., Veldhuizen, S., Adair, C. E., Bourque, J., Distasio, J., Streiner, D. L. (2015). A randomized controlled trial in five Canadian cities of the effectiveness of housing first with assertive community treatment for persons with serious mental illness and a history of homelessness. Psychiatric Services, 67(3), 275–281.
Sheehan, D., & Lecrubier, Y. (2010). The Mini International Neuropsychiatric Interview Version 6.0 (MINI 6.0). Jacksonville, FL: Medical Outcomes System Inc.
Uttaro, T., & Lehman, A. (1999). Graded response modeling of the Quality of Life interview. Evaluation and Program Planning, 22(1), 41–52. doi:10.1016/S0149-7189(98)00039-1.
Lehman, A. F. (1988). A quality of life interview for the chronically mentally ill. Evaluation and Program Planning, 11(1), 51–62. doi:10.1016/0149-7189(88)90033-X.
Lam, J. A., & Rosenheck, R. A. (2000). Correlates of improvement in quality of life among homeless persons with serious mental illness. Psychiatric Services (Washington, D.C.), 51(1), 116–118.
Lehman, A. F. (1996). Measures of quality of life among persons with severe and persistent mental disorders. Social Psychiatry and Psychiatric Epidemiology, 31(2), 78–88. doi:10.1007/BF00801903.
Lehman, A. F., Postrado, L. T., & Rachuba, L. T. (1993). Convergent validation of quality of life assessments for persons with severe mental illnesses. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 2(5), 327–333.
Lehman, A. F. (1983). The effects of psychiatric symptoms on quality of life assessments among the chronic mentally ill. Evaluation and Program Planning, 6(2), 143–151. doi:10.1016/0149-7189(83)90028-9.
Lehman, A. F., Dixon, L. B., Kernan, E., DeForge, B. R., & Postrado, L. T. (1997). A randomized trial of assertive community treatment for homeless persons with severe mental illness. Archives of General Psychiatry, 54(11), 1038–1043.
Lehman, A. F., Kernan, E., DeForge, B. R., & Dixon, L. B. (1995). Effects of homelessness on the quality of life of persons with severe mental illness. Psychiatric Services (Washington, D.C.), 46(9), 922–926.
Statistics Canada. (2005). Canadian Community Health Survey (Survey). Ottawa, ON: Statistical Society of Canada.
Reavis, J. A., Looman, J., Franco, K. A., & Rojas, B. (2013). Adverse childhood experiences and adult criminality: How long must we live before we possess our own lives? The Permanente Journal, 17(2), 44–48. doi:10.7812/TPP/12-072.
Corrigan, P. W., Salzer, M., Ralph, R. O., Sangster, Y., & Keck, L. (2004). Examining the Factor Structure of the Recovery Assessment Scale. Schizophrenia Bulletin, 30(4), 1035–1041.
Barker, S., Barron, N., McFarland, B. H., & Bigelow, D. A. (1994). A community ability scale for chronically mentally ill consumers: Part I. Reliability and validity. Community Mental Health Journal, 30(4), 363–383.
Boothroyd, R. A., & Chen, H. J. (2008). The psychometric properties of the Colorado Symptom Index. Administration and Policy in Mental Health, 35(5), 370–378. doi:10.1007/s10488-008-0179-6.
Rabin, R., & de Charro, F. (2001). EQ-SD: A measure of health status from the EuroQol Group. Annals of Medicine, 33(5), 337–343. doi:10.3109/07853890109002087.
Ware, J., Kosinski, M., & Keller, S. D. (1996). A 12-item short-form health survey: Construction of scales and preliminary tests of reliability and validity. Medical Care, 34(3), 220–233.
Dennis, M. L., Chan, Y.-F., & Funk, R. R. (2006). Development and validation of the GAIN Short Screener (GSS) for internalizing, externalizing and substance use disorders and crime/violence problems among adolescents and adults. The American Journal on Addictions/American Academy of Psychiatrists in Alcoholism and Addictions, 15 (Suppl 1), 80–91. doi:10.1080/10550490601006055.
Boucekine, M., Boyer, L., Baumstarck, K., Millier, A., Ghattas, B., Auquier, P., & Toumi, M. (2015). Exploring the response shift effect on the quality of life of patients with schizophrenia: An application of the random forest method. Medical Decision Making: An International Journal of the Society for Medical Decision Making, 35(3), 388–397. doi:10.1177/0272989X14559273.
Nakagawa, S., & Schielzeth, H. (2013). A general and simple method for obtaining R2 from generalized linear mixed-effects models. Methods in Ecology and Evolution, 4(2), 133–142. doi:10.1111/j.2041-210x.2012.00261.x.
Zissi, A., Barry, M. M., & Cochrane, R. (1998). A mediational model of quality of life for individuals with severe mental health problems. Psychological Medicine, 28(5), 1221–1230.
Lehman, A. F. (1983). The well-being of chronic mental patients. Archives of General Psychiatry, 40(4), 369–373.
Proust-Lima, C., Philipps, V., & Liquet, B. (2015). Estimation of extended mixed models using latent classes and latent processes: the R package lcmm. arXiv:1503.00890 [stat]. Retrieved from http://arxiv.org/abs/1503.00890.
StataCorp (2013). Stata Statistical Software: Release 13. College Station, TX: StataCorp LP.
Spearman, C. (1910). Correlation calculated from faulty data. British Journal of Psychology (1904), 3(3), 271–295. doi:10.1111/j.2044-8295.1910.tb00206.x.
Barclay-Goddard, R., Epstein, J. D., & Mayo, N. E. (2009). Response shift: A brief overview and proposed research priorities. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 18(3), 335–346. doi:10.1007/s11136-009-9450-x.
Schwartz, C. E., Quaranto, B. R., Rapkin, B. D., Healy, B. C., Vollmer, T., & Sprangers, M. A. G. (2014). Fluctuations in appraisal over time in the context of stable versus non-stable health. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 23(1), 9–19. doi:10.1007/s11136-013-0471-0.
Calsyn, R. J., Morse, G. A., Tempelhoff, B., Smith, R., & Allen, G. (1995). Homeless mentally ill clients and the quality of life. Evaluation and Program Planning, 18(3), 219–225. doi:10.1016/S0149-7189(95)00016-X.
Hubley, A. M., Russell, L. B., Palepu, A., & Hwang, S. W. (2014). Subjective quality of life among individuals who are homeless: A review of current knowledge. Social Indicators Research, 115(1), 509–524. doi:10.1007/s11205-012-9998-7.
Evans, S., & Huxley, P. (2005). Adaptation, response-shift and quality of life ratings in mentally well and unwell groups. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 14(7), 1719–1732.
Ruta, D. A., Garratt, A. M., Leng, M., Russell, I. T., & MacDonald, L. M. (1994). A new approach to the measurement of quality of life: The patient-generated index. Medical Care, 32(11), 1109–1126.
Ahmed, S., Mayo, N. E., Wood-Dauphinee, S., Hanley, J. A., & Cohen, S. R. (2005). Using the patient generated index to evaluate response shift post-stroke. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 14(10), 2247–2257. doi:10.1007/s11136-005-8118-4.
Schwartz, C. E., Sprangers, M. A. G., Oort, F. J., Ahmed, S., Bode, R., Li, Y., & Vollmer, T. (2011). Response shift in patients with multiple sclerosis: An application of three statistical techniques. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation, 20(10), 1561–1572. doi:10.1007/s11136-011-0056-8.
We thank Jayne Barker (2008–2011), Cameron Keller (2011–2012), and Catharine Hume (2012–2015), Mental Health Commission of Canada at Home/Chez Soi National Project Leads; the National Research Team; the 5 site research teams; the site coordinators; and the numerous service and housing providers, as well as persons with lived experience, who have contributed to this project and the research. This research has been made possible through a financial contribution from Health Canada. The views expressed herein solely represent the authors.
This research has been made possible through a financial contribution from Health Canada to the Mental Health Commission of Canada.
Role of the funder/sponsor
The Mental Health Commission of Canada oversaw the conduct of the study and provided training and technical support to the service teams and research staff throughout the project. However, the funder had no role in the analysis and interpretation of the data and preparation, review, or approval of the manuscript.
Conflict of interest
Author CA was on contract to the Mental Health Commission of Canada as the quantitative research lead. Her role was otherwise the same as all other academic investigators. GP, DLS, NM, EL declare they have no conflicts of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
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Powell, G.A., Adair, C.E., Streiner, D.L. et al. Changes in quality of life from a homelessness intervention: true change, response shift, or random variation. Qual Life Res 26, 1853–1864 (2017). https://doi.org/10.1007/s11136-017-1522-8