What Next for QALYs?

The quality-adjusted life-year (QALY) has come under fire lately. In the United States, health reform legislation prohibited use of cost-per-QALY thresholds.¹ The United Kingdom has proposed that the National Institute for Health and Clinical Excellence (NICE), which has influenced reimbursement through cost-per-QALY ratios, will not in the future use such information to make yes or no recommendations; instead NICE's cost-effectiveness assessments would provide an input into price negotiations for technologies.² In Germany, the Institute for Quality and Efficiency in Health Care implemented a new system for evaluating the value of medical technologies but rejected the cost-per-QALY model on ethical and methodological grounds.³ Many countries (including France, Spain, and Italy) have opted for other approaches. Other articles have criticized use of QALYs.^{4 - 5}

The drawbacks of QALYs are well known. QALYs represent health over time as a series of preference-weighted health states, for which the preference or quality weights reflect the desirability of living in the state, typically from perfect health (weighted 1.0) to death (weighted 0.0).⁶ However, the preference weights on which QALYs are based may not capture well how individuals value certain aspects of health (eg, the amount of time experienced in a health state or the order in which states are experienced). The procedure for measuring preferences for health states may exaggerate the importance of the health state in question relative to other aspects of life.⁷ Rankings based on cost-per-QALY ratios may not reflect certain preferences. For example, individuals tend to favor interventions that help those most in need or the vulnerable populations, such as children, regardless of whether these options are efficient from a QALY optimizing standpoint.⁸

It is difficult to be too enthusiastic about the QALY. Those who support the QALY emphasize its attempt to capture preferences, its convenience, and the lack of good alternatives, but also acknowledge its limitations.

Nevertheless, it is unclear why such a simple metric attracts such strong objection.^{4 - 5} The QALY provides a convenient yardstick for measuring and comparing health effects of varied interventions across diverse diseases and conditions. It helps foster consistency and transparency in health care decision making. Rather than being a rule, it is intended to serve as a rough benchmark for health gains and as one of several inputs into decisions. There is not a similar debate around the concept of life expectancy even though it, too, provides a simple benchmark for health gains.

Much of the opposition is unreasonable. For example, critics are particularly troubled that cost-per-QALY thresholds discriminate on the basis of age and disability by favoring younger and healthier populations who have more potential QALYs to gain.⁹ However, older and impaired populations typically fare better than younger and healthier populations in cost-effectiveness analyses because it is generally less efficient to provide care to healthier individuals.¹⁰ Moreover, all alternative policies for resource allocation carry their own ethical dilemmas. For example, an approach that banned the valuation of life extension would mean that spending resources to extend by a month the life of a 100-year-old person who is in a vegetative state cannot be valued differently from spending resources to extend the life of a child by many healthy years.¹

Above all, critics conflate QALYs with rationing. They do not distinguish QALYs as an outcome measure from cost-per-QALY thresholds as a decision tool and seem to blame the QALY for revealing uncomfortable choices in health care. They fault the measure for presenting an unacceptable intrusion into the patient-physician relationship. They imply that QALYs represent an absence of clinical judgment and a loss of control, which could shift from physicians and patients to economists or bureaucrats who themselves do not provide care and who have a cost-containment agenda.

Such arguments suggest deeper ideologies and agendas, not about QALYs as a metric, per se, but about the autonomy of physicians, about whether health is a private or public good, and about the appropriate role of government in health care. The QALY may effectively be a vessel into which stakeholders pour their frustrations about health care, and rejecting the QALY might be a way to register a stance against the health care system.

In the face of such opposition, it is difficult for anyone to embrace QALYs. Experience demonstrates that rigid use of cost-per-QALY thresholds is unacceptable. There is little constituency for it. The lesson of US health reform, in which such thresholds were preemptively and gratuitously prohibited (the law already precluded using the government's clinical research as a mandate), demonstrates the depth of the antagonism. Even officials in private health plans, who have every incentive to maximize health under budget constraints, cannot espouse cost-per-QALYs ratios. Moreover, plans have limited perspectives and time horizons. They are not public health organizations with mandates to increase societal health.

Instead, the United States is focused on bolstering comparative effectiveness research while attempting to reform antiquated payment and delivery systems. Worldwide, payers are moving toward value-based pricing, the idea of using evidence of cost-effectiveness in price negotiations, rather than for yes or no coverage decisions.

Yet, recent actions do not signify a death knell of QALYs so much as resetting expectations for them as payers grope for politically acceptable solutions. Although explicit use of cost per QALY ratios has proven objectionable, the information will endure as a general guide for resource allocation decisions.

For all of its shortcomings, the QALY provides a helpful benchmark in considerations of comparative value. Cost-per-QALY ratios have been endorsed by the US Panel on Cost-Effectiveness in Health and Medicine, composed of physicians, health economists, ethicists, and other health policy experts.¹ They have been supported by various government agencies. Medical specialty societies have cited them in support of clinical guidelines. Researchers have published thousands of cost-per-QALY studies in leading medical and health policy journals. The information will continue to inform a host of questions, such as how frequently to screen for cancer, or how to allocate resources among competing public health programs.

Society could attempt to abandon the idea of a common measure and rely solely on disease-specific metrics and expert judgment based on clinical need. However, that approach would not permit comparisons among diseases and conditions or between treatment and prevention.¹ Most importantly, shunning the QALY would not alter the unsustainability of the health spending trajectory or the need to confront the cross-disease and cross-sector tradeoffs inherent in health choices, but would merely mask them. Although payment reforms and value-based pricing arrangements are welcome initiatives, they do not signal an end for QALYs. Unavoidably, ways are needed to measure the value of health care delivered, especially to inform market-based approaches. And the QALY, perhaps a bit bruised by recent events, will be waiting in the wings.