Although Recent Studies Have Found That Head Injuries Occurring Between

Multiple Choice

Although recent studies have found that head injuries occurring between the ages of 11 and 14 increase the risk for schizophrenia by 65%, what was a noted limitation to this finding?

A) There is a possible confounding effect of the emotional stress caused by the head injury.
B) The sample size was too small to make a strong conclusion.
C) Factors such as risk for comorbid psychological disorders were not properly controlled for.
D) Genetic vulnerability was not taken into account.