2.5. Data analyses
Dichotomous data were analyzed by using the pooled event rates and
OR computed using the Mantel Haenszel method (with 95% Confidence
Interval(CI)). Continuous outcomes measured on the same scale were
expressed as a mean value and standard deviation and were analyzed by
using weighted mean. I-square (I2) test was performed
to assess the impact of study heterogeneity on the results of the
meta-analysis. According to the Cochrane review guidelines, if severe
heterogeneity was present at I2>50%, the
random effect models were chosen. Otherwise, the fixed effect models
were used. Z value (Z) is the overall effect. Moreover, a sensitivity
analysis was conducted by deleting each study individually to evaluate
the quality and consistency of the results. Visual inspection of the
Begg’s test was done to assess publication bias. Stata 14.0 (Stata Corp
LLC, Texas, USA) was used for statistical analysis.
3. Results 3.1. Selected studies
Among 661 retrieved searched articles, 27 articles were finally eligible
with a total of 462 included patients, 23 single arm studies and 4
comparative studies were identified which included a total of 329 and
133 patients respectively. These articles were published from
1998[9] to 2018[10-11]. The
mean age was 68.5±2.3 years (n=403; median:68.0), 52.4% are
males(196/373).