Verification of the Heinis Mental Growth Curve on Results with the Stanford-Binet Tests

Chapter II: Current Construction and Evaluation of Intelligence Tests

“…Kuhlmann (28) found that the Heinis personal constant was as applicable to Stanford-Binet as to his own scale and yielded more constant values on retesting than the IQ. DeForest (14) compared Merrill-Palmer and Minnesota Pre-school Tests and found both correlated about r = .55 with later Binet.…”

The feeble-minded.

“…Not only is the child incapable of catching up with his age-mates, but the older he grows, the greater will be the discrepancy between his mental development and theirs. There are many studies showing a consistent decrease in IQ with age (12,13,19). Of course, these results are subject to the same ambiguity of interpretation as those already discussed on pages 154-156 showing the age decreases in isolated rural environments.…”