DrKirch Is a Psychiatrist and Finds That 70 Percent of His

Multiple Choice

Dr.Kirch is a psychiatrist and finds that 70 percent of his patients qualify as having symptoms of sleep disorders, according to the results of a questionnaire.Dr.Kirch reports that 70 percent of the population must have the same condition as well.However, this study lacks _____ due to his biased sample.

A) convenience sampling
B) expected relative-frequency probabilities
C) generalizability
D) reliability