Quality of life measures used to assess the value of medical treatments fail to capture what matters to patients and carers. A UK project to develop new metrics could lead to an overhaul of how cost-effectiveness is judged
Researchers at Sheffield University in the UK are investigating how quality of life measurements could be extended from the current focus on health-related assessments to cover wider benefits, such as independence and improved relationships with friends and carers.
The work could lead to an overhaul of how Health Technology Assessment (HTA) bodies value new medicines and technologies.
Tessa Peasgood, research fellow at Sheffield University, told Healthy Measures the challenges posed by an ageing society mean carers are an increasingly important group. “Carers’ ability to have social relationships and to stay in employment are not captured at present,” she said. “Health-related quality of life instruments don’t measure the impact of interventions in social care where the goal might not be to change the health state but to improve quality of life.”
At present the standard tool used by HTA agencies for measuring quality of life is EQ-5D, a five-part questionnaire that dates back to 1990.
Although not the first attempt to measure quality of life, its relative simplicity and focus on the five key health areas of mobility, self-care, usual activities, pain/discomfort and anxiety/depression, meant EQ-5D was quickly embraced by health authorities and industry
“It helps that the EQ-5D was quite brief,” said Elly Stolk, scientific team leader at the EuroQol Research Foundation, where EQ-5D was developed. “Patients in clinical trials are burdened with a lot of questionnaires, sometimes with hundreds of items. From the outset, there was agreement that a generic health outcome measure would need to be short.”
The field of health measurement was still in its infancy when the EQ-5D was devised but its uptake was swift, with the UK and the Netherlands among the earliest adopters.
EQ-5D feeds into assessments of the cost-effectiveness of drugs, devices and diagnostics based on measuring how many quality-adjusted life years (QALYs) are gained by using the product.
“[EQ-5D’s] use by policymakers is high,” Stolk said. “This shows the need among decision-makers for a robust way to rationalise healthcare decisions. They need to know how much health they are getting, not just in terms of length of life, but in terms of quality of life.”
However, almost thirty years on, there is a growing sense that the brevity of the EQ-5D leads important information to be lost. “As the number of heath states is infinite, summarising everything to five dimensions will inevitably lead to some aspects being overlooked,” Stolk told Healthy Measures.
Missing the value of innovation
Some in industry complain the full value of their innovations may be missed by the questionnaire while others are calling for the role of carers to be factored into decisions on cost-effectiveness.
For example, by looking only at health outcomes, the benefits to patients of switching from regular injections to oral administration of medication are not currently captured. Similarly, the burden on carers of well-managed dementia versus poorly-managed dementia is not adequately captured in cost-effectiveness debates.
EuroQol and the UK Medical Research Council are jointly funding the Extending the QALY project, which is being carried out by Sheffield and Kent universities, the Office of Health Economics and the UK HTA agency, the National Institute of Health and Care Excellence (NICE).
The 30-month study will explore whether a new outcomes measure can offer a more holistic view of quality of life without becoming too cumbersome.
The different outcomes measures are used in healthcare, social care and public health, make it difficult to compare across these sectors, which is important when thinking about the wider health and social care budget.
Existing tools used in social care and services for older persons take account of daily tasks such as dressing and washing oneself and the role of in-home support. However, tacking these onto the EQ-5D would result in an unwieldy survey, making its uptake less likely. Any new instrument is expected to have about ten items and ideally be easily translated for international use.
“The challenge is to have something that is short, manageable and easy to understand which captures health status but also things like social relationships and autonomy,” said Peasgood. “It needs to be sufficiently short if it is to be incorporated into clinical trials.”
The researchers are reviewing the literature on what quality of life issues are important to service users and carers. Then, using online and face-to-face surveys, the team will seek to shorten a longlist of patient-centric measures into a proposed new instrument which could be tested with service users, including vulnerable elderly populations.
Health economics and psychometric testing have advanced considerably since the EQ-5D was devised, giving the researchers a wealth of techniques to draw from to choose the best questions.
The next challenge will be to score each domain depending on how they impact on quality of life. Patients may attach different weight to living in pain versus living independently, for example.
Any new instrument that emerges from the project will have broader applicability than a health-based measure of quality of life, according to Rosie Lovett, Senior Scientific Adviser at NICE. “It should be applicable not just in health but also for public health and social care initiatives,” she said.
For NICE, calculating quality of life is central to its cost-effectiveness assessment of new treatments. “Depending on the research results, NICE will consider whether and how to include any new quality of life measure in its work,” said Nick Crabb, Programme Director for Scientific Affairs at NICE.
While a broader measure of quality of life is desirable, the success of any new instrument will depend heavily on how it is received by HTA bodies, academics and industry.
“NICE relies on an accurate assessment of quality of life when making decisions about interventions across health and social care. Research is needed to develop new tools to assess quality of life that are equally relevant across these sectors and capture the key things, not just health, that are important to people,” Crabb said.