Making use of the earlier designed computer tests assessing the hand dexterity, a study was performed in which the time of task completion was measured in a group of 88 mentally impaired children aged 7-15 and a group 86 of control children. All the children were also asked to take two types of psychological tests: Wechsler test subscales blocks and puzzles and Bender-Santucci test. Results of the computer tests discriminate these groups of children, indicating statistically significant differences between the corresponding mean values. The values of the Pearson coefficient (0,35 ≤ rp ≤ 0,57) for the control group point to a relatively high correlation between the computer test results and those of psychological tests. The sensitivity and specificity analysis is also presented to show that the computer tests fulfil the criteria for a screening test.