Google Scholar as a Sole Literature Source for Meta-analyses in Otolaryngology Head and Neck Surgery

The strength of meta-analyses lies in the synthesis of data from multiple studies. Current guidelines require a thorough systematic search to maximize results, which usually includes searching multiple academic search systems (ASS). Google Scholar (GS) is considered a promising tool for searching the scientific literature. We aimed to determine whether GS is a valid and sufficient solitary data source for meta-analyses in the field of otolaryngology. Selected ENT-HNS journal was searched for meta-analyses published between 2010 and 2021 that adhered to the systematic reviews and meta-analyses guidelines and precisely followed the search algorithm. The latter was reproduced with GS, and the position of each enrolled study in each meta-analysis was determined. Ten meta-analyses were enrolled, the total number of search results ranged from 57 to 17,949. The number of GS search results was significantly greater than those of other ASS combinations (range 1,360–25,400, P = .006). The number of included papers for each meta-analysis ranged from 5 to 26. The position of all enrolled papers throughout GS searching was in the first 200 GS results in four of 10 meta-analyses. The reference lists of all included papers in the first 200 GS results identified 106 papers out of 108 (98%), while searching until the 500th GS output results identified 107 papers out of 108 papers (99%). GS can serve as a solitary ASS for systematic literature reviews and meta-analyses in the field of otolaryngology. Searching the first 500 or 200 results and including reference lists yields 99% and 98% coverage, respectively.