Figure 2. Respondents from group A and group B reported the estimated number of laparoscopic cholecystectomies completed at the time of their first bile duct injury. A higher percentage of surgeons in group A reported injuries early in their experience compared with group B; however, the frequency of reported first injuries equalized in the category “more than 200 cases.” Approximately one third of surgeons reporting an injury in either group reported that the injury occurred after having completed 200 cases. Although it appears that the incidence of injury is increasing in group B, correction for the size of the category reveals a decreasing injury rate. Beyond 200 cases, the incidence cannot be calculated because the total experience (denominator) is unknown.