Overestimating resistance in field testing of malaria parasites: simple methods for estimating high EC₅₀values using a Bayesian approach

• Main Authors: Brockman Alan, Chotivanich Kesinee, Stepniewska Kasia, Day Nicholas PJ, White Nicholas J
• Format: Article
• Language: English
• Published: BMC 2007-01-01
• Series: Malaria Journal
• Online Access: http://www.malariajournal.com/content/6/1/4
• ISSN: 1475-2875

<p>Abstract</p> <p>Conventional methods of assessing in-vitro antimalarial drug-concentration effect relationships in field testing of fresh isolates assess each parasite isolate individually. This leads to systematic overestimation of EC₅₀values for the most resistant isolates, and thus overestimation of the degree of resistance. In antimalarial drug-susceptibility studies conducted on the north-western border of Thailand the overestimation of EC₅₀for the most resistant isolate ranged from 15% for artesunate to 43% for mefloquine. If isolates cannot be stored for re-testing, more accurate estimations of the degree of resistance can be obtained using a Bayesian approach to data analysis which is described here.</p>