Use of re-attempts measure for evaluating device test results of children with neurological impairments

Severely impaired children with Physical and Neurological Impairments (PNI) often have erratic test responses because of impairments. Very often even the binary (YES/NO) intention of a PNI child cannot be determined because responses are made at the wrong time and conflicting signals are sent. We propose that it is possible to determine intention using significant streaks of successful responses found in the noisy responses. We can use two measures among others to determine intention; the maximum streak size attained in a test run with a device, and the sum of the significant streaks in the test run. The maximum streak size measures consecutive successes and the sum of streaks gives an indication measure of re-attempts. This work is part of a larger study to increase accessibility of PNI children to a cognitive test through the use of new non-hand held devices that interact with a computer. Using the proposed two measures, we are able to compare more closely the performance of the less capable and the more capable PNI children. The results show that the children who are more capable re-attempt in that test when they fail to achieve a target. Conversely the less able children divide into two groups: those that do re-attempt the target and those that do not re-attempt the target dependent however on the device being used. These results provide two measures that are potentially useful for determining the intention of the child undertaking the cognitive test.