Performance of clinical laboratories in South African parasitology proficiency testing surveys between 2004 and 2010.

Performance in proficiency testing (PT) schemes is an objective measure of a laboratory's best performance. We examined the performance of participants in two parasitology PT schemes in South Africa from 2004 through 2010. The average rates of acceptable scores over the period were 58% and 66% for the stool and blood parasite schemes, respectively. In our setting, participation in PT alone is insufficient to improve performance; a policy that provides additional resources and training seems necessary.