Expert prior elicitation and Bayesian analysis of the Mycotic Ulcer Treatment Trial I.

Abstract

PURPOSE:

To perform a Bayesian analysis of the Mycotic Ulcer Treatment Trial I (MUTT I) using expert opinion as a prior belief.

METHODS:

MUTT I was a randomized clinical trial comparing topical natamycin or voriconazole for treating filamentous fungal keratitis. A questionnaire elicited expert opinion on the best treatment of fungal keratitis before MUTT I results were available. A Bayesian analysis was performed using the questionnaire data as a prior belief and the MUTT I primary outcome (3-month visual acuity) by frequentist analysis as a likelihood.

RESULTS:

Corneal experts had a 41.1% prior belief that natamycin improved 3-month visual acuity compared with voriconazole. The Bayesian analysis found a 98.4% belief for natamycin treatment compared with voriconazole treatment for filamentous cases as a group (mean improvement 1.1 Snellen lines, 95% credible interval 0.1-2.1). The Bayesian analysis estimated a smaller treatment effect than the MUTT I frequentist analysis result of 1.8-line improvement with natamycin versus voriconazole (95% confidence interval 0.5-3.0, P = 0.006). For Fusarium cases, the posterior demonstrated a 99.7% belief for natamycin treatment, whereas non-Fusarium cases had a 57.3% belief.

CONCLUSIONS:

The Bayesian analysis suggests that natamycin is superior to voriconazole when filamentous cases are analyzed as a group. Subgroup analysis of Fusarium cases found improvement with natamycin compared with voriconazole, whereas there was almost no difference between treatments for non-Fusarium cases. These results were consistent with, though smaller in effect size than, the MUTT I primary outcome by frequentist analysis. The accordance between analyses further validates the trial results. (ClinicalTrials.gov number, NCT00996736.).

• Authors: Catherine Q Sun, N Venkatesh Prajna, Tiruvengada Krishnan, Jeena Mascarenhas, Revathi Rajaraman, Muthiah Srinivasan, Anita Raghavan, Kieran S O'Brien, Kathryn J Ray, Stephen D McLeod, Travis C Porco, Nisha R Acharya, Thomas M Lietman
• Journal: Investigative ophthalmology & visual science (Invest Ophthalmol Vis Sci) Vol. 54 Issue 6 Pg. 4167-73 (Jun 14 2013) ISSN: 1552-5783 [Electronic] United States
• PMID: 23702779 (Publication Type: Clinical Trial, Phase I, Journal Article, Randomized Controlled Trial, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Antifungal Agents
• Pyrimidines
• Triazoles
• Natamycin
• Voriconazole

Topics

• Antifungal Agents (therapeutic use)
• Bayes Theorem
• Corneal Ulcer (drug therapy)
• Expert Testimony
• Eye Infections, Fungal (drug therapy)
• Fusariosis (drug therapy)
• Humans
• Natamycin (therapeutic use)
• Pyrimidines (therapeutic use)
• Surveys and Questionnaires
• Triazoles (therapeutic use)
• Voriconazole