How much feedback is necessary for learning to suture?

Background: Many laparoscopic simulation training systems exist and have been shown to transfer learning of surgical skills to the operating room. The manner in which the training is structured to maximize learning has not been examined. There are many aspects to the acquisition of laparoscopic skills during training, one of which is the availability of knowledge of results (KR). Knowledge of results is information about the outcome of motor skill execution, usually provided to individuals at the end of the execution. The timing and nature of KR can affect how well people learn new motor skills. In addition, detailed instruction during learning can also affect skill acquisition. We studied the effects of KR and instruction on the learning curve of a suturing and knot-tying task. We hypothesized that KR was necessary for skill acquisition, and that detailed instruction would help trainees to learn to perform the task more correctly and reach a performance plateau earlier. In addition, the overall workload of a trainee during training would decrease as skills improved, especially when KR and coaching were provided. Methods: Nine medical students with no previous laparoscopic surgical experience were randomly and evenly divided into three groups with different KR conditions: (1) no KR, (2) KR, (3) KR + instruction. Each subject attended a training session for 1 h each day, 6 days a week for 4 consecutive weeks. Performance measures such as task time, smoothness of instrument, and path length were recorded for each trial. Workload was assessed using the NASA-TLX questionnaire. Results: While KR was necessary for learning to suture, continual instruction had limited additional benefits. However, KR + instruction did reduce subjects' perceived overall workload. Conclusions: Surgical training could be carried out effectively with only knowledge of results. These results have implications for the staffing of surgical skills laboratories.