Unis 2002.

Study characteristics
Methods	4‐week parallel study of secretin versus placebo
Participants	Inclusion criteria: children aged 3‐12 years DSM‐4 diagnosis of autism or PDD‐NOS non‐verbal IQ of > 55 Exclusion criteria: any other medical condition "for which autism was considered symptomatic (for example Fragile X, or tuberous sclerosis)" previously been in receipt of secretin been on psychotropic drug treatments within the past 6 months children with any known pork allergies Setting: not described Sample size: 85 Number of dropouts: 4 participants discontinued, the infusion was not given (2), decided against the infusion (1), did not return for follow‐up assessment (1). Another child developed illness and a fever after infusion and did not complete the study. Mean age: 6.5 years Gender: details not provided IQ: mean IQ of 55 Baseline ABC‐I or other BoC: scores were > 57 at baseline Concomitant medications: psychotropic medications were not permitted during the study or in the 6 months prior to the study except for "occasional symptomatic use for sleep, etc" Previous medications: details not provided
Interventions	Intervention (secretin): single infusion of 0.4 ug/kg synthetic secretin given intravenously over a 2‐minute period, or single infusion of 2 CU/kg biologic secretin given intravenously over a 2‐minute period Comparator (placebo): single infusion of placebo intravenously over a 2‐minute period
Outcomes	Primary outcomes: ABC‐I (change from baseline) (Aman 1985) Secondary outcomes: none reported Timing of outcome assessments: baseline and week 4 (endpoint)
Notes	Study start date: June 1999 Study end date: May 2000 Funding: "Unis, Munson, Abbott, and Dawson were supported by a grant from the NICHD and the NIDCD (PO1HD34565). Dr. Rogers was supported by a grant from the NICHD (PO1HD35468). Drs. Rogers, Gabriels, and Goldson were also supported by ADD grant 90dd041401 and MCH grant MCJ08941301. Dr. Goldson was also supported by a grant from the NCRR (MO1‐RR00069)". Conflicts of interest: none declared Trial registry: NCT00065962
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Children were then randomly assigned to treatment group"
Allocation concealment (selection bias)	Unclear risk	Quote: "Children were then randomly assigned to treatment group"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "parents, teachers and investigators were all blind to treatment (allocation)"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "parents, teachers and investigators were all blind to treatment (allocation)"
Incomplete outcome data (attrition bias) All outcomes	High risk	5 participants were reported to have not completed the study however only 77/85 results were reported for ABC‐I. Up to 40% missing data (see table 1) for teacher‐reported ABC‐I
Selective reporting (reporting bias)	Low risk	Outcome measures included in trials registry reported
Other bias	High risk	All participants were responders to secretin from previous open‐label trial