Psychometric validation of a multi-dimensional capability instrument for outcome measurement in mental health research (OxCAP-MH)

Health and Quality of Life Outcomes

Research

Tom Burns¹  Judit Simon²  Paul Anand³  Alastair Gray⁴  Jorun Rugkåsa⁵  Crispin Jenkinson⁶  Francis Vergunst⁷ 

[1] Department of Psychiatry, University of Oxford, Warneford Hospital, OX3 7JX, Oxford, UK;Department of Psychiatry, University of Oxford, Warneford Hospital, OX3 7JX, Oxford, UK;Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, OX3 7LF, Oxford, UK;Department of Health Economics, Center for Public Health, Medical University of Vienna, Kinderspitalgasse 15, 1090, Vienna, Austria;Faculty of Arts and Social Sciences, The Open University, MK7 6AA, Milton Keynes, UK;Centre for Philosophy of Natural and Social Sciences, London School of Economics, WC2A 2AE, London, UK;Department of Social Policy and Intervention, University of Oxford, 32 -37 Wellington Square, OX1 2ER, Oxford, UK;Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, OX3 7LF, Oxford, UK;Health Services Research Unit, Akershus University Hospital, 1478, Lørenskog, Norway;Centre for Care Research, University College of Southeast Norway, 3900, Porsgrunn, Norway;Health Services Research Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, OX3 7LF, Oxford, UK;Research Unit on Children’s Psychosocial Maladjustment, University of Montréal, Ste Justine Hospital, 3175 Chemin de la Côte Ste-Catherine, H3T 1C5, Montréal, Canada;Department of Psychiatry, University of Oxford, Warneford Hospital, OX3 7JX, Oxford, UK;

关键词: Outcome measurement;    Capabilities;    Psychometric validation;    Mental health;    Psychiatry;    Psychosis;    Community treatment orders;   

DOI  :  10.1186/s12955-017-0825-3

 received in 2017-08-03, accepted in 2017-12-12,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundPatient reported outcome measures (PROMs) are widely used in mental healthcare research for quality of life assessment but most fail to capture the breadth of health and non-health domains that can be impacted. We report the psychometric validation of a novel, multi-dimensional instrument based on Amartya Sen’s capability approach intended for use as an outcome measure in mental health research.MethodsThe Oxford Capabilities Questionnaire for Mental Health (OxCAP-MH) is a 16-item self-complete capability measure that covers multiple domains of functioning and welfare. Data for validation of the instrument were collected through a national randomised controlled trial of community treatment orders for patients with psychosis. Complete OxCAP-MH data were available for 172 participants. Internal consistency was established with Cronbach’s alpha; an interclass correlation coefficient was used to assess test-retest reliability in a sub-sample (N = 50) tested one week apart. Construct validity was established by comparing OxCAP-MH total scores with established instruments of illness severity and functioning: EuroQol (EQ-5D), Brief Psychiatric Rating Scale (BPRS), Global Assessment of Functioning (GAF) and Objective Social Outcomes Index (SIX). Sensitivity was established by calculating standard error of measurement using distributional methods.ResultsThe OxCAP-MH showed good internal consistency (Cronbach’s alpha 0.79) and test-retest reliability (ICC = 0.86). Convergent validity was evidenced by strong correlations with the EQ-5D (VAS 0.52, p < .001) (Utility 0.45, p < .001), and divergent validity through more modest associations with the BPRS (−0.41, p < .001), GAF (0.24, p < .001) and SIX (0.12, p = ns). A change of 9.2 points on a 0–100 scale was found to be meaningful on statistical grounds.ConclusionsThe OxCAP-MH has demonstrable reliability and construct validity and represents a promising multi-dimensional alternative to existing patient-reported outcome measures for quality of life used in mental health research.

【 授权许可】

CC BY   
© The Author(s). 2017

【 图 表 】

Fig. 2