The subjects were psychiatric outpatients at the UCLA Aftercare Research Program in Los Angeles. One of the most challenging
tasks the investigators faced was determining how strictly the patients were adhering to their medication schedule. The investigators
used a combination of patient self-reports, clinician judgments, pill counts, and concentrations of medication in the patients'
blood plasma. They followed the patients for 18 months, observing that 32 percent of patients took their antipsychotics as
prescribed, while others were found to have mild (33 percent), moderate (16 percent), or severe (19 percent) nonadherence.