Summaries and recommendations of the global impression method

With the increase in the number of acupuncture clinical trials, systematic reviews are used to summarize key results across many disciplines. Meta-analysis is a popular method for synthesizing evidence as it provides a succinct way of summarizing evidence quantitatively. Due to clinical heterogeneity, however, it is not always possible to use meta-analysis. Instead, a qualitative method is used. The purpose of this paper is to summary the findings of current research on the Global Impression Method (GIM); a method used to synthesize the results of clinically heterogeneous randomized controlled trial (RCT) in systematic reviews. The results indicate that there is moderate to substantial intra-rater and inter-rater agreement when judging the results of the forest plots using a global impression and simplified version of the best evidence synthesis (BES) method when compared to the results of meta-analyses. Thus, the GIM can be used for researchers to synthesize results of RCT. The quality of the individual study can be taken into consideration after this process to determine a more precise strength of the evidence, therefore, GIM worthy to be used in acupuncture or other studies.