Table 1.
The Cochrane Collaboration's tool for assessing risk of bias.
Figure 1.
The process of identifying relevant studies is summarized.
Table 2.
Characteristics of included randomized controlled trials.
Figure 2.
Review authors' judgments about each risk of bias item for each included study. + is “yes”, − is “no”,? is “unclear”.
Figure 3.
Forest plot of comparison Adjacent segment disease.
The result indicates that there were fewer Adjacent segment disease comparing CDA to ACDF, but the difference was not statistically significant.
Figure 4.
Forest plot of comparison Adjacent segment reoperations.
The result indicates that there were fewer there were fewer Adjacent segment reoperations comparing CDA to ACDF, but the difference was also not statistically significant.