Time dependent covariate model - Infection vs. No Infection
## Call:
## coxph(formula = Surv(tstart, tstop, tech.failure.or.death) ~
## infection, data = tdata)
##
## n= 13835, number of events= 4556
##
## coef exp(coef) se(coef) z Pr(>|z|)
## infection 0.99547 2.70598 0.03315 30.03 <2e-16 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## exp(coef) exp(-coef) lower .95 upper .95
## infection 2.706 0.3696 2.536 2.888
##
## Concordance= 0.598 (se = 0.003 )
## Rsquare= 0.065 (max possible= 0.996 )
## Likelihood ratio test= 930.1 on 1 df, p=0
## Wald test = 901.9 on 1 df, p=0
## Score (logrank) test = 952.2 on 1 df, p=0
Time to Tech Failure by Early/Late Groups; Time 0 set at 1 yr
## Call: survfit(formula = Surv(Time2Fu, Event) ~ group, data = dat2,
## start.time = cut.day)
##
## n events median 0.95LCL 0.95UCL
## group=Early (<0.5yr) 1759 863 2.89 2.73 3.17
## group=Late (>0.5yr) 6052 2585 3.67 3.51 3.85
## yr1 yr2 yr3 yr4 yr5 yr6 yr7 yr8 yr9 yr10
## group=Early (<0.5yr) 1358 822 468 260 167 100 58 27 6 0
## group=Late (>0.5yr) 4966 3139 1884 1165 722 447 263 131 39 0
## Call:
## coxph(formula = Surv(rep(cut.day, nrow(dat2)), Time2Fu, Event) ~
## group, data = dat2)
##
## n= 7811, number of events= 3448
##
## coef exp(coef) se(coef) z Pr(>|z|)
## groupLate (>0.5yr) -0.24645 0.78157 0.03933 -6.266 3.71e-10 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## exp(coef) exp(-coef) lower .95 upper .95
## groupLate (>0.5yr) 0.7816 1.279 0.7236 0.8442
##
## Concordance= 0.53 (se = 0.004 )
## Rsquare= 0.005 (max possible= 0.999 )
## Likelihood ratio test= 37.63 on 1 df, p=8.543e-10
## Wald test = 39.26 on 1 df, p=3.712e-10
## Score (logrank) test = 39.46 on 1 df, p=3.353e-10
Time to Tech Failure by Early/Late Groups; Time 0 set at 1st Infection
## Call: survfit(formula = Surv(Time2Fu - Time2Infection, Event) ~ group,
## data = dat3, start.time = cut.day)
##
## n events median 0.95LCL 0.95UCL
## group=Early (<0.5yr) 1601 748 2.95 2.77 3.26
## group=Late (>0.5yr) 722 326 2.97 2.71 3.53
## yr1 yr2 yr3 yr4 yr5 yr6 yr7 yr8 yr9 yr10
## group=Early (<0.5yr) 1228 753 410 241 150 91 52 24 5 0
## group=Late (>0.5yr) 549 306 184 98 60 33 18 7 0 0
## Call:
## coxph(formula = Surv(Time2Fu - Time2Infection, Event) ~ group,
## data = dat3)
##
## n= 2714, number of events= 1390
##
## coef exp(coef) se(coef) z Pr(>|z|)
## groupLate (>0.5yr) 0.32712 1.38697 0.05531 5.914 3.34e-09 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## exp(coef) exp(-coef) lower .95 upper .95
## groupLate (>0.5yr) 1.387 0.721 1.244 1.546
##
## Concordance= 0.561 (se = 0.007 )
## Rsquare= 0.012 (max possible= 0.999 )
## Likelihood ratio test= 33.94 on 1 df, p=5.693e-09
## Wald test = 34.98 on 1 df, p=3.338e-09
## Score (logrank) test = 35.29 on 1 df, p=2.844e-09