Great efforts focus on early detection of autism spectrum disorder, although some scientists and policy-makers have questioned early universal screening. The aim of this meta-analysis was to evaluate the diagnostic accuracy of the different screening tools. Several electronic databases were used to identify published studies. A Bayesian model was used to estimate the screening accuracy. The pooled sensitivity was 0.72 (95% CI 0.61-0.81), and the specificity was 0.98 (95% CI 0.97-0.99). Subgroup analyses to remove heterogeneity indicated sensitivity was 0.77 (95% CI 0.69-0.84), and specificity was 0.99 (95% CI 0.97-0.99; SD = 0.01). Level 1 screening tools for ASD showed consistent statistically significant results and therefore are adequate to detect autism at 14-36 months.