2.5. Literature selection and data extraction

The first step is to import the retrieved literature into EndNote X8 to remove duplicates automatically, then primary screening will be performed independently by 2 reviewers (Zhihong Zhu and Haitao Jin) based on titles and abstracts, and studies not meeting the selection criteria will be removed directly. The second step is to conduct a full-text screening to select eligible articles by the same 2 reviewers, and the exclusion reasons will be recorded individually. The third step is to carry out a cross-checking of the results to ensure the consistency of the screening. When the disagreements appeared, a third senior assessor (Yue Zhuo) will be asked to assist in the ultimate judgement. The specific selection process is illustrated in Figure ​Figure11.

Flow chart of study selection.

When the above steps are completed, a data extraction table, which mainly includes first author's name, nationality, publication year, participants’ characteristics (sample size, gender, mean age, number of groups, type of NB after SCI, disease duration, and so on), interventions, comparators, outcomes, and methodological design will be established in Microsoft Excel 2016 in light of recommendations in the Cochrane Handbook. Given that baseline situation among different trials may be potentially varying, the data finally included in the analysis were estimated by the following formula, which was recommended in the Cochrane Handbook for Systematic Reviews of Interventions (version5.1) and r is a correlation coefficient with a value of 0.5.^[17] This approach allowed for a better presentation of the changes before and after treatment of dissimilar Chinese medicine interventions.