A Study on a Stopping Strategy for Systematic Reviews Based on a Distributed Effort Approach

Systematic reviews are scientific investigations that use strategies to include a comprehensive search of all potentially relevant articles and the use of explicit, reproducible criteria in the selection of articles for review. As time and resources are limited for compiling a systematic review, limits to the search are needed. In this paper, we describe the stopping strategy that we have been designed and refined over three years of participation to the CLEF eHealth Technology Assisted Review Task. In particular, we present a comparison of a Continuous Active Learning approach that uses either a fixed amount or a variable amount of resources according to the size of the pool. The results show that our approach performs on average much better than any other participant in the CLEF 2019 eHealth TAR task. Nevertheless, a failure analysis allows to understand the weak points of this approach and possible future directions.