Author
- Nikki McCaffrey1
- Flinders University1
2013
Excerpt
Generic multi-attribute utility weights underpinning the widely applied quality adjusted life year measure incorporate multiple domains of health but do not include important palliative care patient-valued domains, e.g. preferences for place of care. Cost-consequence analysis allows consideration of such multiple consequences, but methods thus far fail to account for joint uncertainty and so may lead to incorrect inferences about net benefit when informing societal decision-making. Consequently, a new method is presented, multiple outcome comparison on the cost-disutility plane, which enables joint consideration of multiple outcomes and costs under uncertainty.
The relative merits of the new method versus conventional economic analysis are investigated using trial- and model-based economic evaluations in palliative care. Partial analysis of single effects on the cost-effectiveness plane is illustrated to lead to inferential bias associated with effect selection and inability to allow for effect interaction. The proposed method avoids such problems. Summary measures for deterministic and stochastic analyses are developed including: expected net loss planes (estimate the expected incremental net benefit between strategies across threshold values for multiple outcomes); the expected net loss contour (identifies the strategy maximising expected net benefit and the expected value of perfect information across values across multiple outcomes); and cost-effectiveness acceptability planes (represent the probability of a strategy maximising the expected net benefit across threshold values for multiple outcomes). Collectively, these measures enable robust trade-offs between expected costs and multiple outcomes for multiple strategies, and deliberation of the consequences of suboptimal allocation decisions.
Consideration of multiple outcomes is particularly important in palliative care. To aid appropriate multiple outcome comparison in cost-effectiveness analyses an instrument (the end of life patient-reported outcome measure [EOLPRO]) was developed to allow inclusion of a key palliative care domain, the ability to finalise affairs in preparation for death. This domain is rarely included in existing measures. Content validity was evaluated using data from nine cognitive interviews with purposively sampled Australian palliative care patients. A secondary analysis of data from a randomised controlled trial comparing subcutaneous ketamine and placebo for the ma..nagement of cancer pain was conducted to assess: construct validity; test-retest reliability; and responsiveness. Thematic analysis suggested that the EOLPRO measures patients' ability to complete physical tasks and finalise practical matters in preparation for death but it is unclear whether relationship issues were comprehensively captured. The secondary analysis suggested the EOLPRO has promising psychometric properties. Further testing is required to verify whether emotional tasks and relationship issues are contemplated by respondents and to support the reliability and responsiveness of the EOLPRO.
In conclusion, this thesis has contributed a novel, alternative approach to economic evaluation which better informs: inference with multiple outcomes and multiple strategies; optimisation across strategies; and funding decisions, including the need for future research. The method has been illustrated via cost-effectiveness analyses of palliative care interventions where consideration of multiple outcomes is particularly salient. A new instrument quantifying the ability to finalise affairs in preparation for death has been developed as a valuable, supplementary tool to existing quality of life questionnaires to aid appropriate multiple outcome comparison in palliative care.
The relative merits of the new method versus conventional economic analysis are investigated using trial- and model-based economic evaluations in palliative care. Partial analysis of single effects on the cost-effectiveness plane is illustrated to lead to inferential bias associated with effect selection and inability to allow for effect interaction. The proposed method avoids such problems. Summary measures for deterministic and stochastic analyses are developed including: expected net loss planes (estimate the expected incremental net benefit between strategies across threshold values for multiple outcomes); the expected net loss contour (identifies the strategy maximising expected net benefit and the expected value of perfect information across values across multiple outcomes); and cost-effectiveness acceptability planes (represent the probability of a strategy maximising the expected net benefit across threshold values for multiple outcomes). Collectively, these measures enable robust trade-offs between expected costs and multiple outcomes for multiple strategies, and deliberation of the consequences of suboptimal allocation decisions.
Consideration of multiple outcomes is particularly important in palliative care. To aid appropriate multiple outcome comparison in cost-effectiveness analyses an instrument (the end of life patient-reported outcome measure [EOLPRO]) was developed to allow inclusion of a key palliative care domain, the ability to finalise affairs in preparation for death. This domain is rarely included in existing measures. Content validity was evaluated using data from nine cognitive interviews with purposively sampled Australian palliative care patients. A secondary analysis of data from a randomised controlled trial comparing subcutaneous ketamine and placebo for the ma..nagement of cancer pain was conducted to assess: construct validity; test-retest reliability; and responsiveness. Thematic analysis suggested that the EOLPRO measures patients' ability to complete physical tasks and finalise practical matters in preparation for death but it is unclear whether relationship issues were comprehensively captured. The secondary analysis suggested the EOLPRO has promising psychometric properties. Further testing is required to verify whether emotional tasks and relationship issues are contemplated by respondents and to support the reliability and responsiveness of the EOLPRO.
In conclusion, this thesis has contributed a novel, alternative approach to economic evaluation which better informs: inference with multiple outcomes and multiple strategies; optimisation across strategies; and funding decisions, including the need for future research. The method has been illustrated via cost-effectiveness analyses of palliative care interventions where consideration of multiple outcomes is particularly salient. A new instrument quantifying the ability to finalise affairs in preparation for death has been developed as a valuable, supplementary tool to existing quality of life questionnaires to aid appropriate multiple outcome comparison in palliative care.