Table 3. Cox regression estimates of mortality rate ratios in the screening programme.

Variable	Rate ratio (95% CI)
Birth cohort (1 birth year)	0.97 (0.93 – 1.02)
Males (reference females)	2.13 (1.77 – 2.59)
Cartago (reference PZ)	1.12 (0.93 – 1.35)
Screening groups
Unscreened before	2.06 (1.23 – 3.46)
Unscreened after	1.73 (1.18 – 2.53)
Screened <2 years	1.24 (0.63 – 2.45)
Screened 2–7 years	1.00 Reference

CI=confidence interval; PZ=Pérez Zeledón.