Background and Aims: Wide-area transepithelial sampling with 3-dimensional computer-assisted analysis (WATS-3D) has been shown to increase the diagnostic yield of intestinal metaplasia (IM) and dysplasia within a segment of suspected or known Barrett's esophagus (BE) when used as an adjunct to forceps biopsies. Few data are available regarding how segment length affects WATS-3D yield. The purpose of this study was to evaluate adjunctive WATS-3D use in patients with varying lengths of BE. Methods: A total of 8471 patients (52.5% male; mean age, 63 years) enrolled in 2 registry studies were included in this study. All patients were being screened or surveyed for BE with both forceps biopsies and WATS-3D. The adjunctive and absolute yield of WATS-3D was calculated according to the length of the patient's BE segment. Results: The overall adjunctive and absolute increased diagnostic yields with WATS-3D were 47.6% and 17.5%, respectively, for detection of IM, and 139% and 2.4% for detection of dysplasia. IM and dysplasia detection both increased with the use of WATS-3D regardless of segment length. Increase in IM diagnostic yield was significantly higher in short- versus long-segment cases but higher in long-segment cases for dysplasia detection. Conclusions: This study shows that when WATS-3D is added as an adjunct to forceps biopsies, it is effective at increasing the diagnostic yield of both BE and associated dysplasia in patients with both short and long segments of esophageal columnar-lined epithelium.