Table 1 Characteristics of participants in the study.

Fisher’s exact test was used to test whether the distribution of individuals randomized to the treatment conditions differed by sex and by ethnicity; no significant effects were found. For age, IQ, pretreatment SRS-2 T score, pretreatment CGI-S score, pretreatment blood AVP concentration (in picograms per milliliter), and pretreatment blood AVPR1A:OXTR gene expression, differences between treatment conditions were tested with a simple one-way general linear model; no significant effects were discerned. The values are reported as means ± SE. F, female; M, male; IQ, Intelligence Quotient; SRS-2, Social Responsiveness Scale, 2nd Edition; CGI-S, Clinical Global Impression-Severity; AVP, arginine vasopressin AVPR1A:OXTR, relative gene expression as the ΔΔCt of AVPR1A and OXTR gene expression.

TreatmentnSexEthnicityAge (years)Full-scale
IQ score
SRS-2 T scoreCGI-S scoreBlood AVP
AVP17314899.14 ± 0.5777.65 ± 5.0378.12 ± 1.664.82 ± 0.151.32 ± 0.252.25 ± 0.31
Placebo132111129.86 ± 0.6591.85 ± 5.7683.00 ± 1.904.77 ± 0.171.28 ± 0.292.21 ± 0.35