METHODS: The current investigation extends a recently published study in the International Endodontic Journal (Nagendrababu V, Faggion Jr CM, Pulikkotil SJ, Alatta A, Dummer PM Methodological assessment and overall confidence in the results of systematic reviews with network meta-analyses in Endodontics. International Endodontic Journal 2022;55:393-404) that assessed the methodological quality of systematic reviews with NMAs in Endodontics using the A MeaSurement Tool to Assess systematic Reviews (AMSTAR 2) tool. In the present study, the PRISMA for NMA checklist with 32 items was used to assess the reporting quality of the systematic reviews with NMAs (n = 12). Two independent assessors assigned '1' when an item was completely addressed, '0.5' when it was partially addressed, and '0' when it was not addressed. Disagreements were resolved through reviewer discussion until consensus was reached. If conflicts persisted, a third reviewer made the final decision. The PRISMA for NMA scores were shared with the relevant authors of the individual reviews to reduce the likelihood of misinterpretation and verify the scores assigned. The results for each individual item of the PRISMA-NMA items were calculated by summing the individual scores awarded; the maximum score for each item was 12.
RESULTS: All the systematic reviews with NMAs adequately reported the following items: Title, Introduction section (Objectives), Methods section (Eligibility criteria and Information sources), Results section (Study selection, Study characteristics and Risk of bias within studies), and Discussion section (Summary of evidence). The items that were reported least often were the "geometry of the network" and "the summary of network geometry" with only 2 manuscripts (17%) including these items.
CONCLUSION: A number of the items in the PRISMA-NMA checklist were adequately addressed in the NMAs; however, none adequately reported all the PRISMA-NMA items. The inadequacies of published NMAs that have been identified should be taken into consideration by authors of NMAs in Endodontics and by editors when managing the peer review process. In future, researchers who are writing systematic reviews with NMAs should comply with the PRISMA-NMA checklist.
CLINICAL RELEVANCE: None of the included systematic reviews with NMA adequately reported all the PRISMA-NMA items. Inadequate reporting of a systematic review with NMA increases the possibility that it will provide invalid results. Therefore, authors should follow the PRISMA-NMA guidelines when reporting systematic reviews with NMA in Endodontics.
MATERIALS AND METHODS: A systematic review was performed in accordance with the 3rd edition of the Centre for Reviews and Dissemination (CRD) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Electronic searches for articles were carried out in the PubMed, Web of Science, and Scopus databases. The quality assessment of the included studies was evaluated using the Newcastle-Ottawa Quality Assessment Scale (NOS) and the new version of the QUADOMICS tool. Meta-analysis was conducted whenever possible. The effect size was presented using the Forest plot, whereas the presence of publication bias was examined through Begg's funnel plot.
RESULTS: A total of nine studies were included in the systematic review. The metabolite profiling was heterogeneous across all the studies. The expression of several salivary metabolites was found to be significantly altered in OPMDs and OCs as compared to healthy controls. Meta-analysis was able to be conducted only for N-acetylglucosamine. There was no significant difference (SMD = 0.15; 95% CI - 0.25-0.56) in the level of N-acetylglucosamine between OPMDs, OC, and the control group.
CONCLUSION: Evidence for N-acetylglucosamine as a salivary biomarker for oral cancer is lacking. Although several salivary metabolites show changes between healthy, OPMDs, and OC, their diagnostic potential cannot be assessed in this review due to a lack of data. Therefore, further high-quality studies with detailed analysis and reporting are required to establish the diagnostic potential of the salivary metabolites in OPMDs and OC.
CLINICAL RELEVANCE: While some salivary metabolites exhibit significant changes in oral potentially malignant disorders (OPMDs) and oral cancer (OC) compared to healthy controls, the current evidence, especially for N-acetylglucosamine, is inadequate to confirm their reliability as diagnostic biomarkers. Additional high-quality studies are needed for a more conclusive assessment of salivary metabolites in oral disease diagnosis.