Background: Medical errors have been increasingly identified as a major source of morbidity and mortality in both outpatient and acute care settings. Central to the evaluation of many medical problems, the 12-lead electrocardiogram (ECG) is susceptible to both technical and interpretative errors. Proper interpretation, however, is dependent on the quality and accuracy of the acquired ECG., Methods: We evaluated the impact of both a newly designed electrocardiograph and a newly developed automated computer algorithm on the incidence and detection of electrode cable reversals (lead reversals). The study tested the association of the incidence of electrode cable reversals and the design of the connection terminal. The study was performed during a 7-month period preceding (53,875 ECGs) and after (53,344 ECGs) the implementation of the new system. Electrode cable reversals occurring in various sites of the medical center were tabulated and compared. We then sought to determine if computer detection algorithms could increase point-of-care detection of electrode cable reversals and, thereby, offset the influence of cardiograph design changes. Two commercially available automated detection algorithms were compared for their abilities to identify electrode cable reversals in our study population., Results: During the 7-month postimplementation period, there was a significant increase in the incidence in electrode cable reversals (0.5% vs 0.1%, P < .001). The incidence of reversals for ECGs obtained in the emergency department was twice that of those obtained within the hospital (0.79% vs 0.38%, P < .01). Automated detection of electrode cable reversals from the 7-month study period increased from 38% to 71% (P < or = .0001), using a recently released automated algorithm supplied by the manufacturer., Conclusions: Electrode cable reversals are a prevalent source of medical errors that receives very little attention by the clinical community. The association of an increase in electrode cable reversals with an altered electrode cable connection terminal, coupled with an increased ability to detect electrode cable reversals using the manufacturer's recently developed algorithms, emphasizes the importance of ongoing research efforts to identify technical errors in electrocardiography.