PSYCHOMOTOR-SKILLS FOR ENDOSCOPIC MANIPULATIONS - DIFFERING ABILITIESBETWEEN RIGHT AND LEFT-HANDED INDIVIDUALS

Objective The objective of this study was to compare the psychomotor a ptitudes relevant to endoscopic manipulations between right-handed and left-handed subjects. Summary Background Data There has been little r esearch on the psychomotor performance in relation to minimal access s urgery and there are no psychomotor tests to evaluate aspects of psych omotor abilities relevant to endoscopic manipulations. Methods A micro processor-controlled psychomotor tester was developed for objective ev aluation of endoscopic performance. The task involved negotiating ten target holes with a probe under videoscopic imaging. Subjects consiste d of two groups of 10 medical students: right- and left-handed. After a prestudy familiarization session, each subject performed two test ru ns with one hand, followed by two runs with the other hand. These test runs were repeated 1 week later. The outcome measures were the total execution time, force on backplate, angular deviations, error rate, an d first-time accuracy. Results A significant difference in the error r ate and first time accuracy was observed between subjects (p < 0.001 a nd p < 0.001, respectively) and between the dominant and nondominant h ands (p < 0.001 and p < 0.025, respectively), with no significant chan ge with practice. Right-handed subjects performed better with either h and in terms of error rate (p < 0.001) and first time accuracy (p < 0. 001). Practice improved the execution time (p < 0.001) and the degree of angular deviations (p < 0.02). Conclusions Right-handed subjects pe rform less errors and exhibit better first time accuracy. The paramete rs that improve with practice reflect the positive effect of training, whereas others, such as errors rate and first time accuracy which do not, reflect innate abilities.