HEDS is part of the School of Health and Related Research (ScHARR) at the University of Sheffield. We undertake research, teaching, training and consultancy on all aspects of health related decision science, with a particular emphasis on health economics, HTA and evidence synthesis.

Friday, 17 March 2017

EQ-5D-5L vs 3L: What are the implications for Cost-Effectiveness Estimates?

The NICE Decision Support Unit has just published a report with that very title.  And the answer to the question is….BIG!

“Nine cost-effectiveness studies conducted alongside clinical trials were used as case studies. Each had existing analyses based on patient completion of the EQ-5D-3L instrument. In each case, we used the copula models to generate a revised analysis based on estimated 5L scores. We compared directly-observed 3L and estimated 5L (EQG and NDB) results.

The  5L  instrument  and  associated  tariff  has  the  effect  of  shifting  mean  utility  scores  further up  the  utility  scale  towards  full  health,  and  compresses  them  into  a  smaller  space.  Thus, improvements  in  quality  of  life  tend  to  be  valued  less  using  5L  than  equivalent  changes measured  with  3L.  In  almost  all  cases,  this  means  that  a  switch  from  3L  to  5L  causes  a decrease  in  the  incremental  QALY  gain  from  effective  health  technologies  and  therefore technologies appear less cost-effective. This is true whether the estimation of 5L is based on EQG or NDB data. However, an important exception is where life extension is a substantial element of health gain, the ICER can reduce rather than increase.

Estimated  incremental  QALY  gains  reduced  by  up  to  75%  when  moving  from  3L  to  5L (EQG dataset) or 87% (NDB dataset).”

You can access it here.