The purpose of this study is to measure test-retest reliability and validate the star shaped test of manual dexterity. The purpose of this is to see if there is any significant learning effect, and if the test can discriminate between individuals who are at their normal skill level, and when they are stressed and/or fatigued. The test is designed to test hand to eye coordination and precision control. This is done by following a star shaped track with a pair of a surgical scissors. this is done 10 times, 5 times clockwise and 5 times counter clockwise. Each time the scissors come into contact with the border of the track, an error is counted. Overall completion time is recorded. As a randomized crossover study, we will have 20 test subjects complete the test 4 times. Each test will be conducted with a pause of two breaks between the tests. Before each test, the test subjects are randomized to: no intervention, physical fatigue prior to testing, distractions during the test or both physical fatigue prior to testing and distractions during the test. All participants will complete a test with all four interventions. Furthermore, a test-retest trial will be conducted on 4 test-subjects. Each subject will complete the test two times with no interventions, with two days apart.