“…All reports, by investigators who joined Ritvo and participated in the multicentre study, employed the same design, as shown in Table 1. The exceptions are the two studies carried out independently from the multicentre study (Gampbell, Perry, Polonsky, Deutsch, Palij & Lukashok, 1986;Gampbell, Small, Palij, Perry, Polonsky, Lukashok & Anderson, 1987, and submitted for publication). Parental interviews, behavioral assessments, serotonin determinations and IQ tests were done at fixed intervals, once a month, 7 times, throughout the study.…”