Content validity of preference-based measures for economic evaluation in chronic obstructive pulmonary disease.

BACKGROUND: Generic preference-based measures (GPBMs) are health-related quality of life (HRQoL) measures commonly used to evaluate the cost-utility of interventions in healthcare. However, the degree to which the content of GPBMs reflect the HRQoL of individuals with chronic obstructive pulmonary disease (COPD) has not yet been assessed. The purpose of this study was to examine the content and convergent validity of GPBMs in people with COPD. METHODS: COPD patients were recruited from healthcare centers in Ontario, Canada. The Patient-Generated Index (PGI) (an individualized HRQoL measure) and the RAND-36 (to obtain SF-6D scores; a GPBM) were administered. Life areas nominated with the PGI were coded using the International Classification of Functioning Disability and Health and mapped onto GPBMs. RESULTS: We included 60 participants with a mean age of 70 and FEV1% predicted of 43. The mean PGI score was 34.55/100 and the top three overarching areas that emerged were: 'mobility' (25.93%), 'recreation and leisure' (25.19%) and 'domestic life' (19.26%). Mapping of the nominated areas revealed that the Quality of Well-Being scale covered the highest number of areas (84.62%), Health Utilities Indices covered the least (15.38% and 30.77%) and other GPBMs covered between 46 and 62%. A correlation of 0.32 was calculated between the SF-6D and the PGI. CONCLUSIONS: The majority of GPBMs covered approximately half of the areas reported as being important to individuals with COPD. When areas relevant to COPD are not captured, HRQoL scores generated by these measures may inaccurately reflect patients' values and affect cost-effectiveness decisions.

Psychometric Properties of Preference-Based Measures for Economic Evaluation in Amyotrophic Lateral Sclerosis: A Systematic Review.

OBJECTIVE: The aim of this review was to synthesize the psychometric properties of generic preference-based measures (PBMs) of health-related quality of life (HRQL) in Amyotrophic Lateral Sclerosis (ALS). METHODS: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four databases were searched from inception to April 2019: OVID Medline, Embase, PsycINFO, and CINAHL. Studies were included if (1) the sample represented individuals with ALS, (2) a generic PBM was utilized and reported on, and (3) information on the psychometric property of a generic PBM was provided. RESULTS: Ninety-one articles were screened, and 39 full-text articles were reviewed. Seven full-text articles were included in this review. The mean age of participants ranged from 58.1 to 63.8 years, and mean time since diagnosis ranged from 20.5 to 44.6 months. Two generic PBMs were found, the EQ-5D-3L (n = 6) and the Quality of Well-Being Self-Administered (QWB-SA) scale (n = 1). Convergent validity of the EQ-5D-3L was large against a global scale of self-perceived health (r = 0.60) and small to large against ALS specific HRQL measures (r = 0.19 to 0.75). For the QWB-SA scale, correlations were small against a generic measure (r = 0.21) and large against ALS specific measures (r = 0.55). The EQ-5D-3L discriminated across different disease severity; however, floor effects were reported. CONCLUSION: This review highlights the need for more rigorously designed studies to assess the psychometric properties of generic PBMs in ALS and the development of an ALS specific PBM that adequately reflects the health concerns of individuals with ALS.

Measurement properties of preference-based measures for economic evaluation in COPD: a systematic review.

PURPOSE: Preference-based measures can provide measurements of health-related quality of life and be utilized for cost-effectiveness analyses of interventions in individuals with chronic obstructive pulmonary disease (COPD). The purpose of this study is to evaluate whether generic preference-based measures are reliable, valid, and responsive in COPD. METHODS: A systematic review was performed using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) guidelines. Three databases were searched: MEDLINE, EMBASE, and CINAHL. Studies were included if the sample represented individuals with COPD and the aim was to evaluate one or more psychometric properties or the interpretability of generic preference-based measures. RESULTS: Six hundred and sixty-seven abstracts were screened, 65 full-text articles were reviewed and 24 articles met the inclusion criteria. Measures which emerged from the search were the EQ-5D, the SF-6D, the Quality of Well-being scale, the 15D, and the Health Utilities Index 3. Evidence for the test-retest reliability of these measures was limited. Construct validity of the measures was well supported with correlations with generic health profiles being 0.37-0.68, and correlations with COPD-specific health profiles being 0.53-0.75. Evidence for known-groups validity of these measures was poor and data on responsiveness were mixed. CONCLUSION: Generic preference-based measures' sensitivity to change and ability to discriminate between different disease severities in COPD was poorly supported. Future research may consider examining the development of COPD-specific preference-based measures that may allow for a more accurate detection of change and discrimination among disease severities to facilitate cost-effectiveness evaluations.