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DEFINING QUALITY OF LIFE FOR ONCOLOGIC DRUG APPROVAL. Carol M. Moinpour, PhD Southwest Oncology Group Statistical Center Fred Hutchinson Cancer Research Center Seattle, Washington/USA ODAC QUALITY OF LFE SUBCOMMITTEE February 10, 2000. What is Quality of Life?. Subjective
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DEFINING QUALITY OF LIFE FOR ONCOLOGIC DRUG APPROVAL Carol M. Moinpour, PhD Southwest Oncology Group Statistical Center Fred Hutchinson Cancer Research Center Seattle, Washington/USA ODAC QUALITY OF LFE SUBCOMMITTEE February 10, 2000
What is Quality of Life? • Subjective • Patient perception is critical • Health-related • Yes, we are primarily measuring health status • Multidimensional • Which dimensions are relevant? • Usually not driven by psychosocial theories
Proposal: Data Source Expert re: “patient benefit” = patient Best equipped to evaluate claims about impact of treatment
Quality of Life Vs Health-Related QOL (HRQL) • Not feasible to measure the myriad of non-medical influences • Restrict QOL domains likely to be affected by medical intervention (HRQL) • Attribution problem • Randomization addresses unmeasured factors • Combine quality with quantity of life?
Proposal: QOL vs HRQL • Restrict quality of life assessments to HRQL • Patients asked to report current status • Address known covariates • HRQL can include duration of life • A complicated question deserving our attention
Examples of Quality of Life Domains Physical Functioning Spirituality Occupational/Role Functioning Future Orientation Social Functioning Sexuality/Intimacy Emotional Functioning Health Concerns Symptom Status Family Well-Being Financial Concerns Satisfaction w/Care Global/Overall Perception of Quality of Life
HRQL Domains • Inclusion of symptoms important because • Corroborate physician-rated toxicities • Document palliation in advanced stage disease • Need to examine the “reach” of better/worse symptoms to general functioning
Assessment of Multiple HRQL Dimensions • Specifies how treatments affect patients • Complements physician-related toxicity information • Informs patients and physicians about risks/benefits tradeoffs • Identifies ways to improve cancer treatments • Identifies survivors rehabilitation needs
Proposal: HRQL Domains • Three basic domains • Psychological • Physical • Social • [Global HRQL vs summary score?] • Measure symptoms but also document their effect on basic domains
Proposal: HRQL Domains • Symptom status is not a manifestation of patient HRQL • Sx outcomes alone should not be called HRQL • Sx outcomes alone may be appropriate in Phase II, single institution, or supplemental submissions • Sx outcomes can be designated primary • Clinical issues should drive content of sx measures
Proposal: Role of Theory • Psychological or social science theories usually not driving HRQL assessment design • Psychometric theory has done so • First obligation: identify HRQL issues critical to evaluating treatments • Can suggest broad impacts on the patient • Tx rationale usually doesn’t address HRQL
HRQL Research Issues • Independence of HRQL dimensions • Incorporation of importance ratings? • Impact of substantial individual variation conclusions re: patient benefit • Integration of symptom and basic domain data • To document scope of patient benefit/harm • Validity of total scores with symptom component • Role of methodological and theory-driven research in defining HRQL for drug claims?
Problem with Single Item Measures • Only 1 chance to capture concept or dimension • OK for detecting moderate to large differences • Attractive for clinical trials (burden issue) • Likely to miss differences at individual patient level • Compromise - brief, multi-item scales
World Health Organization Definition “Health is not only the absence of infirmity and disease but also a state of physical, mental and social well-being.”