- Continuing growth of the research spectrum of practice-based research networks (PBRNs) creates a need (1) for new approaches to training clinicians in research protocols and (2) to standardize clinician data collection. Each existing training method has shortcomings when used in geographically dispersed PBRNs. We describe here the use and costs of Internet-based training in support of a research protocol across a PBRN consortium.Clinicians in 4 PBRNs in the PRIME Net consortium participated in training for a study of acanthosis nigricans (AN). We compared results of pre- and posttraining assessments of knowledge and ability to correctly diagnosis AN. We also calculated costs for placement of the training on the Internet.Among 103 participating clinicians, statistically significant increases in knowledge acquisition were demonstrated for all but 2 of the individual topics and in total scores on the assessments. AN diagnostic sensitivity increased from 52% to 99% to 96% to 100%, whereas specificity increased from 70% to 96% to 74% to 97%. Total costs for the web aspects of the training were $3732.The Internet can be an effective and feasible alternative method for training clinicians in support of PBRN research.