The key contributors to the high
between-study heterogeneity assessed by the ‘leave one-out’
sensitivity analysis were the studies conducted by Smith et al.
and Chen et al. After excluding these studies,low heterogeneity
(I²¼23.90%, P heterogeneity¼0.231)was found, and the meta-SMR
was 1.85(1.72 to 1.99).The meta-SMR remained significant when
studies were excluded one at a time in jackknife sensitivity
analyses.