INTRODUCTION: EUS and ERCP each represent hybrids of endoscopy and radiology that require special expertise and equipment. Despite these similarities, reimbursement for EUS is less than for ERCP. HYPOTHESIS: Physician resource utilization for EUS and ERCP as determined by procedure length is similar. AIM: Compare EUS and ERCP procedure lengths from a large multicenter database. METHODS: We performed a retrospective review of the CORI (Clinical Outcomes Research Initiative) database of all EUS (recorded 2/4/98 - 6/30/99) and ERCPs (recorded 6/30/97 - 6/30/99). Data were analyzed as to demographics and procedure length (minutes) of upper EUS vs ERCP, with subset analysis of EUS with fine needle aspiration (FNA) vs. therapeutic ERCP (ERCP with at least one therapeutic procedure: sphincterotomy, stent placement/replacement, stone removal, dilation). Statistical analysis was performed using the JMP module of SAS software. P-values were calculated using Student's T-test. RESULTS: 1452 upper EUS exams (65% male & 35% female) and 2110 ERCPs (57% male & 43% female) were recorded during the periods specified. EUS was performed by 42 endoscopists (60% University based, 40% VA based) at 19 sites (50% University, 50% VA). ERCP was performed by 103 endoscopists (60% University based, 28% VA based, 12% private practice) at 28 sites (69% University, 23% VA, 8% private practice). The mean age of patients undergoing upper EUS vs. ERCP was 61.0±13.6 yrs vs. 55.3 ± 17.5 yrs (mean ± SD, p<0.0001). Data on procedure length was available in 1073(74%) of upper EUS cases vs. 1380(65%) of ERCPs. The mean procedure length of upper EUS vs. ERCP was only 2 1/2 minutes different: 39.8 ± 22.7 min vs. 42.3 ± 26.2 min (mean ± SD,p=0.01). When comparing EUS with FNA (n=318) to therapeutic ERCP (n=615), data on procedure length was available in 215(68%) and 379(62%) cases, respectively. The mean procedure length of EUS with FNA vs. therapeutic ERCP was 61.2 ± 23.3 min vs. 47.7 ± 28.2 min (mean ± SD,p<0.0001). CONCLUSIONS:(1) Resource utilization as reflected in the average procedure length is similar for EUS and ERCP. (2)The average procedure length of EUS with FNA is substantially longer than therapeutic ERCP. (3) Given the complexity of both procedures, procedure lengths, need for additional specialized training, and demands on technical/nursing support, these data favor at least equal financial reimbursement for EUS procedures.