From: Influence of exposure differences on city-to-city heterogeneity in PM2.5-mortality associations in US cities
Cluster
Na
Pooled estimate
95% CI
1
16
−0.01
−0.31–0.29
2
5
0.41
−0.28–1.1
3
34
0.25
−0.15–0.65
4
17
0.66
0.35–0.97
0.50
−0.27–1.3