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Computes the Restricted Mean Time Lost (RMTL) for competing risks based on the integrated Aalen-Johansen estimator.

Usage

cif_yearslost(formula, data = data, cens.code = 0, times = NULL, ...)

Arguments

formula

Formula for phreg object with strata to indicate strata, or +1 if no strata.

data

Data frame for calculations.

cens.code

Censoring code (needed to separate event codes from censorings).

times

Possible times for which to report restricted mean. Summary displays estimates for these times.

...

Additional arguments passed to phreg.

Value

An object of class "resmean_phreg" containing:

cumhaz

Matrix of cumulative hazards (years lost).

se.cumhaz

Standard errors.

intF1times

Years lost at specified times.

causes

Vector of cause codes.

Details

A set of time points can be given to be returned in the summary, but the function computes years-lost for all event times and can be plotted/viewed. The RMTL for a specific time-point can also be computed using the rmstIPCW function.

Author

Thomas Scheike

Examples

data(bmt)
bmt$time <- bmt$time + runif(408) * 0.001

## Years lost decomposed into causes
drm1 <- cif_yearslost(Event(time, cause) ~ strata(tcell, platelet), data = bmt, times = c(40, 50))
par(mfrow = c(1, 2))
plot(drm1, cause = 1, se = 1)
plot(drm1, cause = 2, se = 1)

summary(drm1)
#> $estimate
#> $estimate$intF_1
#>                       strata times    intF_1 se.intF_1 lower_intF_1
#> tcell.0..platelet.0        0    40 16.718647  1.162628    14.588407
#> tcell.0..platelet.1        1    40  9.728016  1.609499     7.033849
#> tcell.1..platelet.0        2    40  9.953058  3.221203     5.278056
#> tcell.1..platelet.1        3    40  8.302397  2.871793     4.214767
#> tcell.0..platelet.0.1      0    50 21.367831  1.476647    18.661101
#> tcell.0..platelet.1.1      1    50 12.979253  2.047517     9.527304
#> tcell.1..platelet.0.1      2    50 12.645366  4.089961     6.708456
#> tcell.1..platelet.1.1      3    50 11.809339  3.673686     6.418465
#>                       upper_intF_1
#> tcell.0..platelet.0       19.15995
#> tcell.0..platelet.1       13.45413
#> tcell.1..platelet.0       18.76891
#> tcell.1..platelet.1       16.35436
#> tcell.0..platelet.0.1     24.46716
#> tcell.0..platelet.1.1     17.68192
#> tcell.1..platelet.0.1     23.83638
#> tcell.1..platelet.1.1     21.72801
#> 
#> $estimate$intF_2
#>                       strata times    intF_2 se.intF_2 lower_intF_2
#> tcell.0..platelet.0        0    40  6.121405 0.8509979     4.661408
#> tcell.0..platelet.1        1    40  6.388328 1.2998315     4.287395
#> tcell.1..platelet.0        2    40 10.497731 2.8144210     6.207118
#> tcell.1..platelet.1        3    40  9.264319 2.9840973     4.927606
#> tcell.0..platelet.0.1      0    50  8.149712 1.0945194     6.263607
#> tcell.0..platelet.1.1      1    50  8.690047 1.7124397     5.905904
#> tcell.1..platelet.0.1      2    50 14.608620 3.7302702     8.856401
#> tcell.1..platelet.1.1      3    50 12.075080 3.8902302     6.421823
#>                       upper_intF_2
#> tcell.0..platelet.0       8.038689
#> tcell.0..platelet.1       9.518773
#> tcell.1..platelet.0      17.754191
#> tcell.1..platelet.1      17.417710
#> tcell.0..platelet.0.1    10.603763
#> tcell.0..platelet.1.1    12.786681
#> tcell.1..platelet.0.1    24.096897
#> tcell.1..platelet.1.1    22.705012
#> 
#> 
#> $total.years.lost
#> [1] 22.84005 16.11634 20.45079 17.56672 29.51754 21.66930 27.25399 23.88442
#> 
estimate(drm1, cause = 1)
#> [[1]]
#>                     Estimate Std.Err   2.5% 97.5%   P-value
#> tcell=0, platelet=0   16.719   1.163 14.440 19.00 6.905e-47
#> tcell=0, platelet=1    9.728   1.609  6.573 12.88 1.502e-09
#> tcell=1, platelet=0    9.953   3.221  3.640 16.27 2.003e-03
#> tcell=1, platelet=1    8.302   2.872  2.674 13.93 3.840e-03
#> 
#> [[2]]
#>                     Estimate Std.Err   2.5% 97.5%   P-value
#> tcell=0, platelet=0    21.37   1.477 18.474 24.26 1.861e-47
#> tcell=0, platelet=1    12.98   2.048  8.966 16.99 2.312e-10
#> tcell=1, platelet=0    12.65   4.090  4.629 20.66 1.989e-03
#> tcell=1, platelet=1    11.81   3.674  4.609 19.01 1.306e-03
#> 
estimate(drm1, cause = 2)
#> [[1]]
#>                     Estimate Std.Err  2.5%  97.5%   P-value
#> tcell=0, platelet=0    6.121   0.851 4.453  7.789 6.329e-13
#> tcell=0, platelet=1    6.388   1.300 3.841  8.936 8.890e-07
#> tcell=1, platelet=0   10.498   2.814 4.982 16.014 1.915e-04
#> tcell=1, platelet=1    9.264   2.984 3.416 15.113 1.906e-03
#> 
#> [[2]]
#>                     Estimate Std.Err  2.5% 97.5%   P-value
#> tcell=0, platelet=0     8.15   1.095 6.004 10.29 9.627e-14
#> tcell=0, platelet=1     8.69   1.712 5.334 12.05 3.882e-07
#> tcell=1, platelet=0    14.61   3.730 7.297 21.92 8.994e-05
#> tcell=1, platelet=1    12.08   3.890 4.450 19.70 1.910e-03
#> 

## Comparing populations
drm1 <- cif_yearslost(Event(time, cause) ~ strata(tcell, platelet), data = bmt, times = 40)
summary(drm1, contrast = list(1:4))
#> $testintF_1
#>             Estimate Std.Err   2.5% 97.5%   P-value
#> [p1] - [p2]    6.991   1.985 3.0991 10.88 0.0004302
#> [p1] - [p3]    6.766   3.425 0.0535 13.48 0.0482015
#> [p1] - [p4]    8.416   3.098 2.3439 14.49 0.0065978
#> ────────────────────────────────────────────────────────────
#> Null Hypothesis: 
#>   [p1] - [p2] = 0
#>   [p1] - [p3] = 0
#>   [p1] - [p4] = 0 
#>  
#> chisq = 17.643, df = 3, p-value = 0.0005211
#> 
#> $testintF_2
#>             Estimate Std.Err    2.5% 97.5% P-value
#> [p1] - [p2]  -0.2669   1.554  -3.312 2.778  0.8636
#> [p1] - [p3]  -4.3763   2.940 -10.139 1.386  0.1366
#> [p1] - [p4]  -3.1429   3.103  -9.225 2.939  0.3111
#> ────────────────────────────────────────────────────────────
#> Null Hypothesis: 
#>   [p1] - [p2] = 0
#>   [p1] - [p3] = 0
#>   [p1] - [p4] = 0 
#>  
#> chisq = 3.0579, df = 3, p-value = 0.3828
#> 
#> $estimate
#> $estimate$intF_1
#>                     strata times    intF_1 se.intF_1 lower_intF_1 upper_intF_1
#> tcell=0, platelet=0      0    40 16.718647  1.162628    14.588407     19.15995
#> tcell=0, platelet=1      1    40  9.728016  1.609499     7.033849     13.45413
#> tcell=1, platelet=0      2    40  9.953058  3.221203     5.278056     18.76891
#> tcell=1, platelet=1      3    40  8.302397  2.871793     4.214767     16.35436
#> 
#> $estimate$intF_2
#>                     strata times    intF_2 se.intF_2 lower_intF_2 upper_intF_2
#> tcell=0, platelet=0      0    40  6.121405 0.8509979     4.661408     8.038689
#> tcell=0, platelet=1      1    40  6.388328 1.2998315     4.287395     9.518773
#> tcell=1, platelet=0      2    40 10.497731 2.8144210     6.207118    17.754191
#> tcell=1, platelet=1      3    40  9.264319 2.9840973     4.927606    17.417710
#> 
#> 
#> $total.years.lost
#> [1] 22.84005 16.11634 20.45079 17.56672
#> 
e1 <- estimate(drm1)
estimate(e1, rbind(c(1, -1, 0, 0)))
#>                           Estimate Std.Err  2.5% 97.5%   P-value
#> [tcell=0, platelet=0]....    6.991   1.985 3.099 10.88 0.0004302
#> ────────────────────────────────────────────────────────────
#> Null Hypothesis: 
#>   [tcell=0, platelet=0] - [tcell=0, platelet=1] = 0 
#>  
#> chisq = 12.3964, df = 1, p-value = 0.0004302