Are Cleft Palate Persons of Sub-Normal Intelligence?

Abstract

THE SPEECH anomalies of those with cleft palates have led many to believe that these handicapped people are, as a group, of intelligence. The lay person is naturally led to believe this to be true. The distortion and nasality of their speech, together, often, with their reluctance to speak unless prodded, gives them the outward manifesta tion of the mentally deficient. However, social workers, psychologists, and educators usually maintain that the sub-normal intelligence is more apparent than real. It was to throw some light on this question that Mrs. May made the study (1) which is reported in summary here. The Lancaster (Pa. ) Cleft Palate Clinic has records of s eve ral hun dred cleft palate patients. These individuals are for the most part resi dents of the state of Pennsylvania, but a number do come from other sections of the country. Nearly all of these patients are given the Ver bal Section of the Wechsler Bellevue Intelligence Test or the 1937 Revi sion of the Stanford Binet Examination. By taking an uns elected sample from these case studies, it was hoped that it would be possible to ascer tain whether the intelligence of cleft palates is distributed with the same degree of variability as in a representative group. For this reason, 200 cases were taken by chance from the files in order to secure the unse lected sample. All Binet IQ's were translated into their Wechsler IQ equivalents through use of the table given by Wechsler in his manual (2). Computa tion of the median IQ for residents and non-residents of Pennsylvania gave 95. 4 and 110. 8, respectively. It seemed obvious, therefore, that the non-residents were a selected group. Hence, the 49 non-residents' cases were eliminated from the study. The occupations of the individuals or their parents were available for 132 of the remaining 151 cases. Table I gives the data from which Chi Square was computed in order to determine goodness of fit with the 1940 census of occupations for Pennsylvania. Chi Square is 20.7 9. P f or