Helping Trainees Understand the Strategies to Minimize Errors and Biases in Systematic Review Approaches

Over the past few decades, there has been major development in methods for evidence synthesis, which can lead to confusion as to which approaches to use and why. Several strategies can be used in systematic review approaches to reduce potential biases and errors. These strategies can be considered on a spectrum ranging from least to most likely to minimize biases and errors in the review process. Building on the existing literature of synthesis methods and biases, a five-level spectrum of systematicity in reviews is proposed in this paper. For each of the main steps of the review process (i.e. search, selection, data extraction, appraisal, and synthesis), potential biases are presented. Then, strategies are suggested and ordered based on their influence on potential biases and errors in the review process. The levels of systematicity suggested can help to distinguish the reviews based on their rigour. This paper can contribute to improving understanding of the variety of strategies that can be used at the different steps of a review process. This can be particularly useful for students and novice researchers seeking to understand the potential sources of bias and to choose suitable strategies for their review.