Following the traces of critical memories: A meta-analysis on the diagnostic accuracy of the Reaction Time - Concealed Information Test

The Reaction Time - Concealed information Test (RT-CIT) is a memory detection technique that uses the measurement of reaction times to identify the "guilty" or "hidden" knowledge of certain critical details knowable only to a person involved in the crime under investigation. A marked difference in reaction times to relevant (crime-related) and irrelevant stimuli, known as the “RT-CIT effect”, will reveal the recognition of critical information by the examinee. RT-CIT has potential in terms of the few resources required (technological, economic, temporal) and admissibility within Italian criminal proceedings. We conducted a meta-analysis on the diagnostic accuracy of the RT-CIT quantified by the global accuracy index "Area Under the Curve” (AUC). As far as we are aware, this is a novel analysis. Following the PRISMA guidelines, we proceeded to construct the research question through the PICOS criteria. These criteria guided the bibliographical research, carried out on PubMed and Google Scholar. After identifying 235 articles, 30 relevant studies were selected and information required to quantify the AUC and for conducting the subgroup analyses were extracted. Statistical analysis showed that the RT-CIT can be considered a memory detection technique with moderately high diagnostic accuracy. However, the unexplained heterogeneity that remained even after the previously planned subgroup analyses did not allow to exclude the possibility that the RT-CIT may prove to be an uninformative test or, on the contrary, highly accurate. Despite the limitations of this meta-analysis, related to the source of information used and the moderators investigated, as well as the uncertainty in being able to extend the results obtained through laboratory experiments to real-life situations, these preliminary indications, together with the potentials outlined above, suggest that we should continue to investigate the potentials of the RT-CIT.