Duplicate hepatitis C antibody testing in New York City, 2006-2010.

Repeating a hepatitis C virus antibody test for a person who previously tested positive provides no new information, wastes resources, and may reflect poor coordination of medical care. Using public health surveillance data collected by the New York City Department of Health and Mental Hygiene, we evaluated the magnitude of duplicate antibody testing and assessed patient-level and facility-level risk factors for duplicate testing. From 2006 to 2010, 70,257 duplicate tests were performed for 58,886 individuals in New York City, costing an estimated $1.4 million. Analyses using a polytomous logistic regression model indicated that individuals in correctional and substance abuse treatment facilities were more likely to undergo duplicate testing. Future efforts should focus on coordinating medical information and care for hepatitis C antibody-positive individuals to ensure that the recommended diagnostic follow-up and treatment services are provided.