Table 3.
Posterior means and 
PIs of the pooled RRs for PTB per IQR increase in different metrics of exposure to PM
| Outcome | Dynamic distributed lag | Standard approach | ||
|---|---|---|---|---|
| Exposure window | IQR ( ) |
window | RR (95% PI) | RR (95% CI) |
| Cumulative | 3.11 | VPTB | 1.07 (1.04, 1.12) | 1.04 (1.02, 1.07) |
| LPTB | 1.01 (0.99, 1.04) | 1.01 (0.99, 1.03) | ||
| PTB | 1.03 (1.00, 1.06) | 1.02 (1.00, 1.03) | ||
| Trimester 1 | 5.22 | VPTB | 1.07 (1.03, 1.11) | 1.06 (1.03, 1.08) |
| LPTB | 1.00 (0.97, 1.02) | 1.00 (0.98, 1.01) | ||
| PTB | 1.01 (0.99, 1.04) | 1.01 (0.99, 1.03) | ||
| Trimester 2 | 5.14 | VPTB | 1.05 (1.02, 1.09) | 1.03(1.01, 1.06) |
| LPTB | 1.02 (1.00, 1.05) | 1.01 (0.99, 1.03) | ||
| PTB | 1.03 (1.01, 1.05) | 1.02 (1.00, 1.03) | ||
| Trimester 3 | 5.43 | VPTB | 1.00 (0.99, 1.00) | 0.99 (0.97, 1.01) |
| LPTB | 1.01 (0.99, 1.03) | 1.00 (0.99, 1.02) | ||
| PTB | 1.00 (0.99, 1.01) | 1.00 (0.98, 1.01) | ||
| First 4 weeks | 5.92 | VPTB | 1.02 (1.00, 1.04) | 1.03 (1.01, 1.05) |
| LPTB | 1.00 (0.98, 1.02) | 1.00 (0.98, 1.01) | ||
| PTB | 1.00 (0.99, 1.02) | 1.00 (0.99, 1.01) | ||
| 4-week lag | 6.04 | VPTB | 1.01 (0.99, 1.03) | 0.98 (0.96, 1.01) |
| LPTB | 1.00 (0.99, 1.02) | 1.00 (0.99, 1.01) | ||
| PTB | 1.00 (0.99, 1.02) | 1.00 (0.98, 1.01) |
Estimates were pooled across all PTB outcome weeks (week 
–36), as well as across very PTB (week 
–
VPTB) and late PTB (week 
–36, LPTB). Under the standard approach, estimates and 
confidence interval (CI) were estimated by a time-to-event model where the weekly exposures were first averaged across the exposure window.