Purpose -The purpose of this paper is to examine the prevalence of posttraumatic stress symptoms (PTSS) in adults and children who were exposed to applied behavior analysis (ABA) autism early childhood intervention. Using an online questionnaire to survey autistic adults and caregivers of autistic children, the author collected data from 460 respondents on demographics, intervention types, and current pathological behaviors with symptom severity scales. This study noted PTSS in nearly half of ABA-exposed participants, while non-exposed controls had a 72 percent chance of being asymptomatic. ABA satisfaction ratings for caregivers averaged neutral or mild satisfaction. In contrast, adult satisfaction with ABA was lower on average and also tended to take on either extremely low or extremely high ratings. Exposure to ABA predicted a higher rate and more severe PTSS in participants, but the duration of exposure did not affect satisfaction with the intervention in caregivers. Design/methodology/approach -Participants were recruited for an online survey through social media networks, adult gatherings, social skills groups, and autism support groups nationwide. Adult inclusion criteria consisted of autismdiagnosed or self-diagnosedand an age of 18 or older. A total of 460 respondents, consisting of autistic adults and caregivers of autistic children, completed an online survey. The caregiver entries (n ¼ 217) concerned 79 percent male children, 21 percent female children (male to female 3.80:1), and one MtF transgender child, ages 1-38, with an average age at diagnosis of 4.69 years. The adult entries (n ¼ 243) concerned 30 percent males, 55 percent females (male to female 0.55:1), and 14 percent other gender, ages 18-73, with an average age at diagnosis of 25.38 years. Findings -Nearly half (46 percent) of the ABA-exposed respondents met the diagnostic threshold for PTSD, and extreme levels of severity were recorded in 47 percent of the affected subgroup. Respondents of all ages who were exposed to ABA were 86 percent more likely to meet the PTSD criteria than respondents who were not exposed to ABA. Adults and children both had increased chances (41 and 130 percent, respectively) of meeting the PTSD criteria if they were exposed to ABA. Both adults and children without ABA exposure had a 72 percent chance of reporting no PTSS (see Figure 1). At the time of the study, 41 percent of the caregivers reported using ABA-based interventions. Originality/value -The majority of adult respondents were female, raising questions about the population of online autistic survey respondents. Further, the high numbers of reported gender other than male or female in the adult respondents, as well as at least on MtF child from the caregiver respondents indicates that future studies should consider these intersections. These accompanied significant discrepancies in reporting bias between caregivers and ABA-exposed individuals, which highlight the need for the inclusion of the adult autistic voice in future intervention design. Based on t...