Adjustment, IQ, Family Size, and Illiteracy
The rising crescendo of concern over stepped-up population increments caused the writer to dust off some data he had collected during World War I1 while he was serving as chief psychological handmaiden to more than 15,000 illiterate soldiers. These men, whose Army Wechsler IQs were in the upper sixties, were administered orally a painstakingly validated, 36-item adjustment test ( 1 ) which was locally constructed. Curiosity as to the relation of family size (median between five and six) to IQ and adjustment among this highly "selected" and unrepresentative group led the writer to calculate the mean IQ and maladjustment scores for the soldier who was an only child ( N = 73) on up the scale, in sequence, to the illiterates from 13-children families (N = 26). Inspection of the data indicated that the extremes, as opposed to in-between groups, might yield significant differences. The mean IQ for extreme groups (families of 1, 2, 12, and 13 children) was 70.85, sigma of 10.48, for 226 soldiers; for the 1,107 Ss from intermediate-sized families, the mean IQ was 68.44, sigma of 10.53. This mean difference in IQs is significant at the .O1 level of confidence. The relative (how appropriate the adjective! ) brightness of the scions of small families needs no justification; and it may be that the anomalous finding concerning the representatives of 12and 13-children families is due to the inability of the parents (already poor) to afford even a modicum of schooling for the entire brood. The mean maladjustment scores for soldiers who came from families of extreme size ( 1,2, 12, 13 children) versus those from families of in-between size diverged significantly ( p = .05 ), the group from the extremes being better adjusted. It should also be noted that 633 soldiers from smaller families ( 1 through 5 children) were better adjusted ( p = .01) than the 700 soldiers from the larger families ( 6 through 13 ) . It would seem, therefore, that higher IQs and better adjustment among illiterates are related to extremes in family size, though it may well be that the reasons differ at each extreme. It would also appear that smaller families ( 1 to 5 children) produce better adjusted adults among this unlettered group.