Thank you, Talentdifferent, for sharing the details on this study.

It seems there was a significant element of self-selection, as eligible inmates elected to take the IQ assessments... or not.

It is interesting that it was determined this self-selected group was representative of the overall incarcerated population... based on "responses within an expected range". To me, this gives the appearance of a study designed to reinforce a foregone conclusion.

As this dates back to 1984, and 33 years have passed, possibly it is time for a new study; one that might include several cities.

Then again, the vast and invasive data collection that we live under may have this information already stored for nearly 100% of the population... including incarcerated persons. It would just be a matter of extracting and reporting.