The use of eye-tracking to find objective outcome measures of early intervention strategies for children with autism: a systematic review.

Objective: Early intervention strategies are recommended for children with autism to improve cognitive and social communication skills. However, there is a persistent challenge to identify objective outcome measures of intervention efficacy. Eye-tracking (ET) is a safe and well-tolerated technology able to detect differences in visual attention through gaze behavior. This systematic review aims to identify, appraise and summarize the existing literature using ET to track response to early intervention in autism clinical trials.

Method: A comprehensive literature search was conducted in December 2024 in several bibliographic databases, including Medline ALL Ovid, Embase.com, APA PsycInfo Ovid, the Cochrane Library Wiley and PubMed Central. Additionally, we searched trial registries and we performed citation tracking strategies. We retained randomized controlled trials (RCTs) incorporating an ET outcome measure to evaluate the effect of direct, parent-mediated and pharmacological early interventions. Quality was assessed using Risk of Bias 2 and GRADE.

Results: Out of 1'726 reports screened, eleven articles from nine unique studies met inclusion criteria, with overall low-to-moderate risk of bias. Six out of the nine intervention approaches showed improvements in several indices of visual attention measured with different ET paradigms. We also identified 24 RCTs registered with an ET outcome measure yet without published results.

Conclusion: ET proved to be a clinically relevant measure sensitive to change in several interventional contexts. However, not all ET paradigms measured change over time reliably, compromising interpretability. Further research is needed to ensure that ET potentially becomes an accessible and accurate tool for widespread adoption in clinical practice.