The 19 practice-based research networks (PBRNs) initially funded by the Agency for Healthcare Research and Quality (AHRQ) constitute a potential research resource with thousands of physicians and more than 7 million patients. In order for this resource to be useful, the physicians and patients in the PBRNs need to be characterized in detail. In response to this RFA, ICJ Medical Group-Primary Care (ILTMG- PC) will be characterized by its research network called IUMG ResNet. Of the 119 primary care physicians currently practicing in ResNet sites, those 77 (65%) practicing at least 2 half-days per week in lUMG-PC sites were surveyed and 66 (86%) agreed to participate in this project. To characterize ResNet's physicians and patients, the National Ambulatory Medical Care Survey (NAMCS) will be administered. Because of its extensive electronic medical'information system, the Regenstrief Medical Record System (RNIRS), ResNet will be able to provide the data in the NAMCS physician survey from established databases. In addition, the RMRS will supply some of the information required by the NAMCS patient visit survey that will be administered to 30 consecutive patients of each participating physician. The methods and timing of administering the patient survey will be decided at a meeting of all PBRNs funded under this AHRQ RFA. Once collected, ResNet will use the data from the patient survey to do validation studies of the RMRS visit data. The data fields to be evaluated will include the reason for the visit, visit diagnoses, disposition, and education, counseling, and other therapy provided by the physician during the visit. These data will allow ResNet to know which information from physician-patient interactions need to be provided b the physicians vs. being retrieved from the RMRS.