Meta-regression for the potential source of heterogeneity.

CI, confidence interval;*Relative diagnostic odds ratio (OR) is <1 when studies with the characteristic produce a lower diagnostic OR and >1 when the reverse is true.CI即置信区间（confidence interval）；*当具备该特征的研究所得到的诊断比值比更低时，相对诊断比值比（Relative diagnostic odds ratio，OR）小于1，反之则大于1。