Measures of Health-Related Quality-of-Life

1. Measures of Health-Related Quality-of-Life Background presentation for IOM Committee on Women’s Health Research May 7, 2009 Dennis G. Fryback, PhD Professor Emeritus, Population Health Sciences University of Wisconsin-Madison dfryback@wisc.edu

2. Mortality-based measures death rates, life expectancies, etc. All the familiar stuff Measures of Health – a quick typology

3. Mortality-based measures death rates, life expectancies, etc. Morbidity-based measures indicators Indicators: Single, countable things TB rate C-section rates % population who exercise Examples: Healthy People 2010 “Leading Indicators” WHO “Core Health Indicators” Measures of Health – a quick typology

4. Mortality-based measures death rates, life expectancies, etc. Morbidity-based measures indicators health status measures disease-, organ-specific Health Status Measures Disease-, organ-specific.... Created to be sensitive to changes in symptoms or functional impairment due to a particular disease process Examples: Arthritis Impact Measurement System (AIMS) Vision Function Questionnaire (VFQ-25) McGill Pain Questionnaire NY Heart Association Classification Some physician-reported, others patient-reported Measures of Health – a quick typology

5. Mortality-based measures death rates, life expectancies, etc. Morbidity-based measures indicators health status measures disease-, organ-specific “generic” Generic Health Status Measures Most famous: SF-36 health profile One questionnaire with many questions  Several questions about each of 8 different domains of health multiple scales to cover broad scope of health, not tied to one disease or organ system Scoring: Arbitrary scales based on summing responses to multiple questions Separate scores for each subscale or health concept PF, RP, BP, GH, VT, SF, RE, MH PCS MCS Measures of Health – a quick typology

6. Mortality-based measures death rates, life expectancies, etc. Morbidity-based measures indicators health status measures disease-, organ-specific Measures of Health – a quick typology

7. Mortality-based measures death rates, life expectancies, etc. Morbidity-based measures indicators health status measures disease-, organ-specific “generic” health-related quality-of-life (HRQoL) indexes HRQoL indexes Like generic health status – try to comprehensively cover conceptual basis of health with multiple questions about health Scoring not simple sums--these are not psychometric scales! econometric methods used to elicit utility weights (“preferences”) for health states 0 = dead, 1= perfect health average preference weights from community sample of people Measures of Health – a quick typology

8. Data Pyramid for Population Health (after Wolfson) more aggregated measures = summarization, evaluation HRQoL Indexes preference-weighted aggregate scores summarizing overall health Generic Health Status Profiles Vector of health status domain scales Disease-specific Scales Do not necessarily cover all health domains Multitude of health indicators more disaggregate measures = explanation, description

9. EuroQol EQ-5D Mobility Self-care Usual activities Pain/discomfort Anxiety/depression Domains addressed by a number of HRQoL indexes QWB-SA • Mobility • Physical activity • Social activity • Symptoms SF-6D (from SF-36 questionnaire) • Physical function • Role limitation • Social function • Pain • Mental health • Vitality HALex • Self-rated health • Physical activity limitations HUI2 • Sensation • Mobility • Emotion • Cognition • Self-care • Pain HUI3 • Vision • Hearing • Speech • Ambulation • Dexterity • Emotion • Cognition • Self-care • Pain

10. EuroQol EQ-5D Mobility Self-care Usual activities Pain/discomfort Anxiety/depression (-0.11 ... 0 ... 1.0) Scale ranges for the HRQoL indexes QWB-SA • Mobility • Physical activity • Social activity • Symptoms 0...(0.09 ... 1.0) SF-6D (from SF-36 questionnaire) • Physical function • Role limitation • Social function • Pain • Mental health • Vitality 0...(0.31 ... 1.0) HUI3 • Vision • Hearing • Speech • Ambulation • Dexterity • Emotion • Cognition • Self-care • Pain (-0.36 ... 0 ... 1.0) HALex • Self-rated health • Physical activity limitations 0...(0.10 ... 1.0) HUI2 • Sensation • Mobility • Emotion • Cognition • Self-care • Pain (-0.02 ... 0 ... 1.0)

11. EuroQol EQ-5D US national sample Preference weights source for the HRQoL indexes QWB-SA San Diego, CA SF-6D (from SF-36 questionnaire) England national sample HUI3 Ontario, Canada HALex (ad hoc US for Healthy People 2000, 2010) HUI2 Ontario, Canada

13. NHMS Design • RDD survey of adults, non-institutionalized, • ages 35-89 • continental US (not Alaska, Hawaii) • Fielded June 2005-Aug 2006 • designed to oversample African Americans and people aged 65+

14. Indexes EQ-5D, SF-36v2TM, HUI2/3, QWB-SA, HALex EQ-5D, SF-36, HUI & QWB randomized US scoring EQ-5D SF-6D derived from SF-36 & SF-12 Other health & well-being CDC QoL questions 2 Psychology of Well-being scales 11 health conditions (NHIS format + follow up questions) 9 Perceived discrimination questions (everyday + lifetime) Personal data Gender, age, race, height, weight, smoking status, marital status, education Socioeconomic data household income, household assets, health insurance status Linked contextual data from US Census (2000) Race, education, economic distributions in census tract Census’ %urban %rural population in tract NHMS: Data collected Now available as public data set: see www.healthmeasurement.org

15. NHMS Sample

16. Means for women seem always a little lower than for men

17. D Cherepanov, in progress, Gender differences in HRQOL

18. (more from Cherepanov, dissertation in progress) • Similar results seen in other US national data sets for ages 35-89: • US Valuation of the EQ-5D (n ~ 2,300) • EQ-5D, HUI2, HUI3 • Medical Expenditure Panel Survey (MEPS) (n~13,200) • EQ-5D, SF-6D • Joint Canada US Survey of Health (JCUSH) (n~3,200) • HUI3 • Differences tend to disappear when incorporate added covariates • education, marital status, household income • Domain-by-domain analyses hint at differential gender effects • Larger gender differences in pain & physical function domains; smaller on social-mental functioning, all sig. before adjustment • After covariate adjustment, differences in pain & physical health remain weakly significant; no diff. on social-mental functioning. • results only tentative so far as many complexities

19. SES & HRQoL in older adults • At every age, significant gradient of differences in HRQoL associated with income, education, assets • Each has independent association net of the others. • Education and income differentials in HRQoL are relatively consistent across adult age groups controlling for other SES measures, race, and gender. • HRQoL differentials associated with household assets are widest through midlife into old age. Robert SA, Cherepanov D, Palta M, Cross Dunham NC, Feeny D, Fryback DG.Socioeconomic status and age variations in health-related quality of life: Results from the National Health Measurement Study. Journal of Gerontology: Social Sciences, 2009 May; 64(3):378-89, [Epub 2009 Mar 23]

20. Gender differences in HRQoL • As far as these indexes go, gender differences mostly because of differential distribution of strong health determinants between older women and men in US population: income, education, marital status?? • Additional: do women and men answer self-report HRQoL questionnaires differently? (“Differential Item Functioning”, DIF) • JA Fleishman, WF Lawrence. Demographic variation in SF-12 scores: true differences or differential item functioning? Med Care 2003;41:III-75—III-86) • Race x gender x instrument interactions??? • Gender differences in weighting of health domains for aggregation?? • Much work to do yet!

21. Summary • Standardized HRQoL indexes offer a window into gender differences in health by aggregating across many facets of health as well as allowing disaggregation. • Available in a number of important population surveys in US and elsewhere (depending on the measure)