Cognitive impairment of schizophrenics. Refer to the LO3 American Journal of Psychiatry (Apr. 2010) study of the differences in cognitive function between normal individuals and patients diagnosed with schizophrenia, Exercise 9.16

(p. 476). Recall that the total time (in minutes) a subject spent on the Trail Making Test was used as a measure of cognitive function. Summary data for independent random samples of 41 schizophrenics and 49 normal individuals are reproduced below. Suppose the researchers theorize that schizophrenics will have a wider range in time on the Trail Making Test than will normal subjects. Is there evidence to support this theory? Test using a = .01.

Schizophrenia Normal Sample size 41 49 Mean time 104.23 62.24 Standard deviation 45.45 16.34