OBJECTIVES: Substantial evidence suggests that following an enhanced recovery after surgery (ERAS) program is effective in improving post-surgical outcomes. To examine the potential associations between compliance with ERAS protocol elements and post-op fluid use, opioid use, hospital length of stay (LOS), hospital costs, and readmissions, would require combining data elements from the ERAS program with regularly collected retrospective data elements in a large multi-hospital database. The objective of this study was to combine information from a prospective dataset with a matched retrospective data source. METHODS: Duke University Medical Center (DUMC) collected data on colorectal surgery patients in order to determine eligibility for inclusion in the study. With IRB approval, we matched selected patients in the Premier research database on criteria of age, gender, discharge date, procedure date, length of stay, presence of a colorectal procedure during stay, and presence of a colorectal procedure. All matches were verified by physicians at DUMC. RESULTS:  Of the 240 patients in the DUMC database, 206 (85.8%) matched on all variables.  One other patient matched, except on having a colorectal procedure on an identical date. Thirteen (5.4%) were a match, except on length of stay.  Expanding the age criteria to ±1 year, we were able to match 7 (2.9%) additional patients.  Similarly, allowing the procedure date to match within ±1 day increased the total by one more patient.  Eight (3.3%) patients required a manual match by discharge date and presence of a colorectal procedure during the hospital stay.  The final four (1.7%) patients could not be matched because their discharge date was outside the range of the Premier database. CONCLUSIONS: Using the different matching approaches criterion, we were able to link nearly all patients from the DUMC prospective database to the Premier retrospective dataset.  This flexible approach can be utilized with other databases.