Objective: To assess the association of specialty training and experience in the care of HIV disease with HIV-specific knowledge, referral patterns, and HIV-related education activities.

Design: Cross-sectional survey.

Setting: The United States.

Participants: Physicians caring for patients in the HIV Costs and Service Utilization Study, a study of a probability sample of HIV-infected individuals in the United States.

Measurements and main results: Measures included physicians' reports of specialty training and HIV caseload, scores on an HIV-specific knowledge test, referral patterns, and attendance rates at HIV-related educational activities. Approximately 72% (379) of the eligible physicians completed a survey. Of these, 152 (40%) had infectious disease (ID) training, and 213 (56%) were generalists; 4% of ID-trained physicians and 37% of generalist physicians did not consider themselves HIV experts. The median current caseloads were 150 and 200 patients for ID experts and generalist experts, respectively. In contrast, the median caseload for non-expert generalists was 5. Mean scores on the knowledge scale were similar for ID and generalist experts (9.0 items correct out of 11 vs 8.5; P=not significant), but lower for generalist non-experts (6.5 items correct; P <.01). Experts had attended more local and national HIV meetings than non-experts (9.3 vs 2.7; P <.01, and 2.3 vs.40; P <.01, respectively) in the past year. Fewer ID experts ever referred than generalist experts (13.0% vs 27.3%; P=.01). In multivariable models that included specialty training and caseload, physicians with caseloads of 20 to 49 and >50 were more likely to have a high knowledge score (defined as 80% or more correct, odds ratio [OR], 2.8; P=.04 and OR, 5.7; P <.001, respectively), and the effect of specialty was attenuated (OR, 2.7; P=.02 decreased from OR, 7.8; P <.001 in a model without caseload). In the models predicting referral practices, both experience (OR,.25; P <.01 and OR,.17; P <.01 for caseloads of 20 to 49 and >50, respectively) and specialty (OR,.19; P <.01 and OR,.09; P <.01 for generalist and ID experts, respectively) were significant.

Conclusions: In a national sample of physicians, HIV-specific knowledge was more strongly associated with HIV caseload than with specialty training. In addition, although referral practices were related to both experience and specialty, generalist experts and ID physicians reported similar behaviors. This suggests that generalist physicians, through clinical experience and self-education, can develop specialized knowledge in HIV care.