2. Full-scale IQ below 75 on the Wechsler Abbreviated Scale of Intelligence (WAIS) or cognitive impairment that would affect a participant's ability to give informed consent or provide interview or self-report data reliably, as determined by the consent monitor and the site psychiatrist. A questionnaire assessing consent comprehension will be used with all study subjects, to ensure that they understand the key procedures of the study, and its risks and benefits. An independent monitor will administer that questionnaire.