Accounting for between-study variation in incremental net benefit in value of information methodology

Journal Article


Abstract


  • Previous applications of value of information methods for determining optimal sample size in randomized clinical trials have assumed no between-study variation in mean incremental net benefit. By adopting a hierarchical model, we provide a solution for determining optimal sample size with this assumption relaxed. The solution is illustrated with two examples from the literature. Expected net gain increases with increasing between-study variation, reflecting the increased uncertainty in incremental net benefit and reduced extent to which data are borrowed from previous evidence. Hence, a trial can become optimal where current evidence is sufficient assuming no between-study variation. However, despite the expected net gain increasing, the optimal sample size in the illustrated examples is relatively insensitive to the amount of between-study variation. Further percentage losses in expected net gain were small even when choosing sample sizes that reflected widely different between-study variation.

Publication Date


  • 2012

Citation


  • Willan, A. R. & Eckermann, S. (2012). Accounting for between-study variation in incremental net benefit in value of information methodology. Health Economics, 21 (10), 1183-1195.

Scopus Eid


  • 2-s2.0-84865865364

Ro Metadata Url


  • http://ro.uow.edu.au/gsbpapers/253

Number Of Pages


  • 12

Start Page


  • 1183

End Page


  • 1195

Volume


  • 21

Issue


  • 10

Abstract


  • Previous applications of value of information methods for determining optimal sample size in randomized clinical trials have assumed no between-study variation in mean incremental net benefit. By adopting a hierarchical model, we provide a solution for determining optimal sample size with this assumption relaxed. The solution is illustrated with two examples from the literature. Expected net gain increases with increasing between-study variation, reflecting the increased uncertainty in incremental net benefit and reduced extent to which data are borrowed from previous evidence. Hence, a trial can become optimal where current evidence is sufficient assuming no between-study variation. However, despite the expected net gain increasing, the optimal sample size in the illustrated examples is relatively insensitive to the amount of between-study variation. Further percentage losses in expected net gain were small even when choosing sample sizes that reflected widely different between-study variation.

Publication Date


  • 2012

Citation


  • Willan, A. R. & Eckermann, S. (2012). Accounting for between-study variation in incremental net benefit in value of information methodology. Health Economics, 21 (10), 1183-1195.

Scopus Eid


  • 2-s2.0-84865865364

Ro Metadata Url


  • http://ro.uow.edu.au/gsbpapers/253

Number Of Pages


  • 12

Start Page


  • 1183

End Page


  • 1195

Volume


  • 21

Issue


  • 10