Fig. 3

Distribution of propensity scores when including age and nonverbal IQ with the full sample (ASD n = 25, TD n = 43). Matched treatment units = children with ASD; matched control units = selected matches of TD children; unmatched control units = remaining unmatched TD children. Propensity scores calculated using the nearest neighbor and optimal matching methods resulted in the same values. This plot indicates the distribution of propensity scores when including covariates of age and IQ for all 25 children with ASD and 43 TD children. We see a similar distribution of propensity scores for matched treatment units and matched control units, ranging from scores of 0.2 to above 0.6. Among the matched treatment units, there appears to be one outlier where a child with ASD was assigned a propensity score of approximately 0.8