Literature reviews can be directly used by clinicians and other health professionals to support many decision-making processes. This review aims to offer health professionals an essential practical guide to critically evaluate and properly understand results of review articles published in the scientific literature. An evidence-based methodological review with step-by-step theoretical concepts and practical suggestions was developed. Key steps of this guide are: to consider the topic and the research question (a), to check the review type (b), to evaluate the methodology (with a keen focus on review guidelines, search strategy and study-selection process, evaluation of the quality and certainty of included evidence, and statistical analysis) (c), and to define the real impact of review results (d). This guide offers a description of essential and easy-to-apply key steps which can help health professionals to evaluate the reliability and implications of a literature review, and to select the latest high-quality scientific evidence to keep updated with.