Systematic review and meta-analysis use in the field of spinal cord injury research: A bibliometric analysis

To subvert issues of low sample sizes and high attrition rates and generate epidemiologically-sound evidence, collaborative research—through international consortia and multi-centric studies—and meta-analysis approaches are encouraged in spinal cord injury (SCI) research. We investigated the use of systematic reviews and meta-analyses (SRMA) methodology in SCI research and evaluated the quality of evidence across publications we identified. We searched the Web of Science Core Collection database by topic without time or language restrictions through 16 December 2022. We identified additional relevant articles through Embase.com. SRMA including human and animal SCI populations were eligible for inclusion. We analyzed data using Bibliometrix and VOSviewer. We used the JBI tool (former Joanna Briggs Institute) to assess methodological quality of a subset of 50 randomly selected articles. We based our analysis on data from 1'224 documents authored by 5'237 scholars and published in 424 sources between 1985 and 2022. The use of SRMA methodology in the field gained momentum in 2009 and a steady increase followed with an annual growth rate of ≈15%. Our findings indicate major research themes in the field include recovery, SCI management, rehabilitation, and quality of life. Over the past 30 years there has been a shift from SRMA concerning functional recovery, secondary health complications, and quality of life toward biomarkers and neuro-regeneration. The major methodological issues across articles we evaluated included opaquely described search strategies, poorly reported critical appraisals, and insufficiently addressing publication bias. In addition, only one-fifth of articles reported review protocol registration. Our bibliometric analysis clearly shows a rapid increase of SRMA applications in SCI research. We discuss the most important methodological concerns we identified among a randomly selected set of articles and provide guidance for improving adherence to methodological and reporting SRMA guidelines.