Cognitive Disorder Among the Schizophrenias

II. Differences Between the Sub-categories

¹ Medical Research Council Unit for Research in the Epidemiology of Psychiatric Illness, Royal Edinburgh Hospital, Morningside Park, Edinburgh, 10
² Department of Psychiatry, University of Edinburgh, Morningside Park, Edinburgh, 10

Forty-eight schizophrenics were given the Payne Object Classification test, the modified Benjamin Proverbs test, the Bannister-Fransella test of "thought-process disorder" and the Paranoid v. Non-paranoid Schizophrenia Scale of the Symptom-Sign Inventory. A 2³ factorial design was used with equal numbers of acutes and active chronics, of paranoids and non-paranoids (as clinically diagnosed) and of males and females.

The results obtained from the Object classification and Proverbs tests do not support Payne's contention that abnormal scores on these tests are associated with the acute rather than the chronic stage of schizophrenia. Unlike the present sample, Payne's chronics may have included a number of "burned-out" cases.

The prediction that acutes and active chronics would not differ on Bannister and Fransella's measures of Intensity and Consistency was confirmed.

Since acute and active chronic patients did not differ on the Pa. v. Sc. Scale, they have not differed on any of the five measures employed.

There was a significant tendency for paranoid schizophrenics, whether diagnosed clinically or by the SSI, to perform more abnormally on the Object Classification test.

On the Proverbs test, clinically diagnosed paranoid schizophrenics performed more abnormally; but this relationship was not significant when diagnosis was by means of the SSI.

Clinically diagnosed non-paranoid schizophrenics were somewhat more Inconsistent in their use of constructs than were paranoid schizophrenics; but the difference was not statistically significant. With non-paranoid schizophrenics as diagnosed by the SSI the relationship was statistically significant.

Both male and female acute paranoids, as clinically diagnosed, obtained less abnormal Intensity scores than non-paranoids; but chronic non-paranoids of both sexes obtained less abnormal scores than did paranoids.

The tendency for SSI diagnosed non-paranoids to score more abnormally on Intensity was not statistically significant. There was, however, a significant tendency for them to score more abnormally than paranoids on Bannister and Fransella's combined measure of "thought-process disorder" (i.e. abnormality on both I and C₂).

Four of the 8 predictions with regard to the performance of paranoid and non-paranoid schizophrenics were supported at an acceptable level of significance. All of the remainder were in the right direction. It seems, therefore, reasonable to conclude that paranoid schizophrenics tend to perform more abnormally than do non-paranoid schizophrenics on the Object Classification and Proverbs tests; whereas non-paranoid schizophrenics tend to perform more abnormally than do paranoid schizophrenics in their use of constructs on the Bannister-Fransella test of "thought-process disorder".