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Discriminant and convergent validity of a subjective quality-of-life instrument aimed at high content validity for schizophrenic persons

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Abstract

Objective

To analyse whether a subjective quality-of-life (QoL) instrument (QLiS—Quality-of-Life in Schizophrenia), developed on the basis of a large number of open-ended interviews with schizophrenic patients, has sufficient discriminant and convergent validity to justify its application as a schizophrenia-specific QoL instrument.

Method

The discriminant and convergent validity of the QLiS (comprising 12 subscales) was analysed in a cross-sectional study. Schizophrenic persons (n = 135) from different care settings were surveyed using the QLiS, the WHOQOL-Bref, the SWN and 7-point satisfaction items. Partial correlational analyses and regression analyses controlling for general life satisfaction were conducted comparing the QLiS subscales with those of the other instruments.

Results

Positive correlation coefficients were found among all subscales of the QLiS and the other QoL instruments (WHOQOL-BREF from r = 0.29 to r = 0.72; SWN, r = 0.14 to r = 0.83; satisfaction scales, r = 0.18 to r = 0.69). One QLiS subscale (cognitive functioning) was shown to be empirically redundant (r>0.80) to the mental functioning subscale of the SWN. All other subscales proved to have unique variance. The non-QLiS QoL instruments only accounted for substantial amounts of variance (>20% after controlling for global life satisfaction) in the QLiS subscales leading a normal life, appreciation by others, appraisal of accommodation/housing and social contacts.

Discussion

Most of the QLiS subscales can be regarded as sufficiently distinct from other QoL instruments, and thus show evidence of discriminant and convergent validity.

Conclusion

A subjective QoL questionnaire with high content validity can provide additional empirical information about schizophrenics’ QoL not accounted for by other common QoL instruments.

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Notes

  1. Franz M, Fritz M, Gallhofer B, Meyer T (accepted for publication) QLiS—Development of a new schizophrenia-specific quality-of-life scale. Health and Quality of Life Outcomes.

  2. Meyer T, Gallhofer B, Franz M. What do schizophrenic persons mean by ‘quality of life’? A content anaylsis of 268 open-ended interviews. Submitted for publication.

References

  1. Pitkänen, A., Välimäki, M., Kuosmanen, L., Katajisto, J., Koivunen, M., Hätönen, H., et al. (2012). Patient education methods to support quality of life and functional ability among patients with schizophrenia: A randomised clinical trial. Quality of Life Research, 21, 247–256.

    Article  PubMed  Google Scholar 

  2. Priebe, S., Katsakou, C., Yeeles, K., Amos, T., Morriss, R., Wang, D., et al. (2011). Predictors of clinical and social outcomes following involuntary hospital admission: A prospective observational study. European Archives of Psychiatry and Clinical Neuroscience, 261, 377–386.

    Article  PubMed  Google Scholar 

  3. Taylor, D., Hanssens, L., Loze, J. Y., Pans, M., L’Italien, G., & Marcus, R. N. (2008). Preference of medicine and patient-reported quality of life in community-treated schizophrenic patients receiving aripiprazole vs standard of care: results from the STAR study. European Psychiatry, 23, 336–343.

    Article  PubMed  Google Scholar 

  4. Becker, T., Leese, M., Krumm, S., Ruggeri, M., Vázquez-Barquuero, J. L., & The EPSILON study group. (2005). Needs and quality of life among patients with schizophrenia in five European centres. Social Psychiatry and Psychiatric Epidemiology, 40, 628–634.

    Article  PubMed  Google Scholar 

  5. König, H. H., Roick, C., & Angermeyer, M. C. (2007). Validity of the EQ-5D in assessing and valuing health status in patients with schizophrenic, schizotypal or delusional disorders. European Psychiatry, 22, 177–187.

    Article  PubMed  Google Scholar 

  6. Ritsner, M. S. (2007). The distress/protection vulnerability model of quality of life impairment syndrome. Current evidence and future research directions. In M. S. Ritsner & A. G. Awad (Eds.), Quality of life impairment in schizophrenia, mood and anxiety disorders (pp. 3–19). Berlin: Springer.

    Chapter  Google Scholar 

  7. Meyer, T. (2004). Vorstellungen schizophrener Menschen über Lebensqualität [Perceptions of quality of life in schizophrenic persons; in German]. Hamburg: Kovac.

    Google Scholar 

  8. Angermeyer, M. C., & Kilian, R. (2006). Theoretical models of quality of life for mental disorders. In H. Katschnig, H. Freeman, & N. Sartorius (Eds.), Quality of life in mental disorders (pp. 21–32). Chichester: Wiley.

    Google Scholar 

  9. Dijkers, M. (1999). Measuring quality of life: Methodological issues. American Journal of Physical Medicine and Rehabilitation, 78, 286–300.

    Article  PubMed  CAS  Google Scholar 

  10. Katschnig, H. (2006). Introduction. In H. Katschnig, H. Freeman, & N. Sartorius (Eds.), Quality of life in mental disorders (pp. 3–18). Chichester: Wiley.

    Google Scholar 

  11. Bobes, J., García-Portilla, P., Sáiz, P. A., Bascarán, T., & Bousoño, M. (2005). Quality of life measures in schizophrenia. European Psychiatry, 20(3), 307–313.

    Article  Google Scholar 

  12. Priebe, S. (2007). Social outcomes in schizophrenia. British Journal of Psychiatry, 191(50), 15–20.

    Article  Google Scholar 

  13. The WHOQOL Group. (1995). The World Health Organization quality of life assessment (WHOQOL): Position paper from the World Health Organization. Social Science and Medicine, 41, 1403–1409.

    Google Scholar 

  14. McKenna, S. P. (1997). Measuring quality of life in schizophrenia. European Psychiatry, 12(3), 267–274.

    Article  Google Scholar 

  15. US Department of Health and Human Services, Food and Drug Administration, et al. (2009). Guidance for industry. patient-reported outcome measures: Use in medical product development to support labeling claims. http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ UCM193282.pdf. Last accessed: 10 October 2011.

  16. Berzon, R. A., Simeon, G. P., Simpson, R. L., Jr, Donnelly, M. A., & Tilson, H. H. (1993). Quality of life bibliography and indexes: 1993 update. Quality of Life Research, 1, 53–73.

    Google Scholar 

  17. Wilkinson, G., Hesdon, O. B., Wild, D., Cookson, R., Farina, C., Sharma, V., et al. (2000). Self-report quality of life measure for people with schizophrenia: The SQLS. British Journal of Psychiatry, 177, 42–46.

    Article  PubMed  CAS  Google Scholar 

  18. Riedel, M., Spellmann, I., Schennach-Wolff, R., Obermeier, M., & Musil, R. (2011). The RSM-scale: A pilot-study on a new specific scale for self- and observer-rated quality of life in patients with schiozphrenia. Quality of Life Research, 20, 263–272.

    Article  PubMed  CAS  Google Scholar 

  19. Nadalet, L., Kohl, F.-S., Pringuey, D., & Berthier, F. (2005). Validation of a subjective quality of life questionnaire (S.QUA.LA) in schizophrenia. Schizophrenia Research, 76, 73–81.

    Article  PubMed  Google Scholar 

  20. Auquier, P., Simeoni, M. C., Sapin, C., Reine, G., Aghababian, V., Cramer, J., et al. (2003). Development and validation of a patient-based health-related quality of life questionnaire in schizophrenia: The S-QoL. Schizophrenia Research, 63, 137–149.

    Article  PubMed  CAS  Google Scholar 

  21. Chou, C. Y., Ma, M. C., Yang, T. T., & Chen-Sea, M. J. (2011). Psychometric validation of the S-QoL Chinese (Taiwan) version for patients with schizophrenia. Quality of Life Research, 20, 763–767.

    Article  PubMed  Google Scholar 

  22. Campbell, D. T., & Fiske, D. W. (1959). Convergent and discriminant validation by the multitrait-multimethod matrix. Psychological Bulletin, 56, 81–105.

    Article  PubMed  CAS  Google Scholar 

  23. Pukrop, R., Moeller, H. J., & Steinmeyer, E. M. (2000). Quality of life in psychiatry: A systematic contribution to construct validation and the development of the integrative assessment tool “modular system for quality of life”. European Archives of Psychiatry and Clinical Neuroscience, 250, 120–132.

    Article  PubMed  CAS  Google Scholar 

  24. Headey, B., Veenhoven, R., & Wearing, A. (1991). Top-down versus bottom-up theories of subjective well-being. Social Indicators Research, 24, 81–100.

    Article  Google Scholar 

  25. Franz, M., Meyer, T., & Gallhofer, B. (1999). Are importance ratings useful in the assessment of subjective quality of life in schizophrenic patients? International Journal of Methods in Psychiatric Research, 8, 204–211.

    Article  Google Scholar 

  26. WHOQOL-Group. (1998). Development of the World Health Organization WHOQOL-BREF quality of life assessment. Psychological Medicine, 28, 551–558.

    Article  Google Scholar 

  27. Angermeyer, M. C., Kilian, R., & Matschinger, H. (2000). WHOQOL-100 und WHOQOL-BREF: Handbuch für die deutschsprachige Version der WHO Instrumente zur Erfassung von Lebensqualität. Göttingen: Hogrefe.

    Google Scholar 

  28. Naber, D. (1995). A self-rating to measure subjective effects of neuroleptic drugs, relationschips to objective psychopathology, quality of life, compliance and other variables. International Clinical Psychopharmacology, 10(3), 133–138.

    PubMed  Google Scholar 

  29. Naber, D., Moritz, S., Lambert, M., Rajonk, F., Holzbach, R., Mass, R., et al. (2001). Improvement of schizophrenic patients’ subjective well-being under atypical antipsychotic drugs. Schizophrenia Research, 50, 79–88.

    Article  PubMed  CAS  Google Scholar 

  30. Franz, M., Plüddemann, K., Gruppe, H., & Gallhofer, B. (1996). Modifikation und Anwendung der Münchner Lebensqualitäts-Dimensionen-Liste bei schizophrenen Patienten [Modification and application of the Munich Quality of Life Dimensions List in schizophrenic patients]. In H.-J. Möller, R. Engel, & P. Hoff (Eds.), Befunderhebung in der Psychiatrie: Negativsymptomatik, Lebensqualität und andere neue Entwicklungen (pp. 103–111). Wien: Springer.

    Chapter  Google Scholar 

  31. Oliver, J. P. J. (1991/1992). The social care directive: development of a quality of life profile for use in community services for the mentally ill. Social Work and Social Science Review, 3, 5–45.

    Google Scholar 

  32. Gaite, L., Vázquez-Barquero, J. L., Arribabalaga, A. A., Vázquez-Bourgon, E., Retuerto, M. P., Schene, A. H., et al. (2000). Quality of life in schizophrenia: Development, reliability and internal consistency of the Lancashire Quality of Life Profile—European Version; EPSILON study 8. British Journal of Psychiatry, 177(39), 49–54.

    Article  Google Scholar 

  33. Kay, S. R., Fiszbein, A., & Opler, L. A. (1987). The Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Schizophrenia Bulletin, 13, 261–276.

    Google Scholar 

  34. American Psychiatric Association (Ed.) (1996). Diagnostic and Statistical Manual of Mental Disorders DSM-IV (German edition and introduction by H. Sass, H.-U. Wittchen and M, Zaudig). Goettingen: Hogrefe.

  35. Franz, M., Meyer, T., Spitznagel, A., Schmidt, H., Wening, K., & Gallhofer, B. (2001). Responsiveness of subjective quality of life assessment in schizophrenic patients: a quasi-experimental pilot study. European Psychiatry, 16, 99–103.

    Google Scholar 

  36. Franz, M., Meyer, T., Reber, T., & Gallhofer, B. (2000). The importance of social comparisons for high levels of subjective quality of life in chronic schizophrenic patients. Quality of Life Research, 9, 481–489.

    Article  PubMed  CAS  Google Scholar 

  37. Wong, A. H. H., Tsang, H. W. H., Li, S. M. Y., Fung, K. M. T., Chung, R. C. K., Leung, A. Y., et al. (2011). Development and initial validation of perceived rehabilitation needs questionnaire for people with schizophrenia. Quality of Life Research, 20, 447–456.

    Article  PubMed  Google Scholar 

  38. Franz, M., Lis, S., Plüddemann, K., & Gallhofer, B. (1997). Conventional versus atypical neuroleptics: Subjective quality of life in schizophrenic patients. British Journal of Psychiatry, 170, 422–425.

    Article  PubMed  CAS  Google Scholar 

  39. Bullinger, M. (1997). Generic quality of life assessment in psychiatry: Potentials and limitations. European Psychiatry, 12, 203–209.

    Article  PubMed  CAS  Google Scholar 

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Acknowledgments

The QLiS was developed with financial support from Novartis Pharma GmbH, Germany.

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Correspondence to T. Meyer.

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Franz, M., Fritz, M. & Meyer, T. Discriminant and convergent validity of a subjective quality-of-life instrument aimed at high content validity for schizophrenic persons. Qual Life Res 22, 1113–1122 (2013). https://doi.org/10.1007/s11136-012-0221-8

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