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This function compares survival curves as modeled with do_kpm(). It outputs a contingency table and a Chisq measure of difference.

Usage

get_survdiff(kds, cond, test_type)

Arguments

kds

data set of a survival model such as do_kpm()

cond

character of experimental condition variable in the data

test_type

numeric (0 or 1) parameter that controls the type of test (0 means rho = 0; log-rank, 1 means rho = 1; Peto & Peto Wilcox)

Value

Returns survival test results as called from survival::survdiff().

Examples

kpm_est <- do_kpm(add_dropout_idx(dropRdemo, 3:54))
get_survdiff(kpm_est$d, "experimental_condition", 0)
#> Call:
#> survdiff(formula = f, data = kds, rho = test_type)
#> 
#>                            N Observed Expected (O-E)^2/E (O-E)^2/V
#> experimental_condition=11 72       72     73.7    0.0407    0.0996
#> experimental_condition=12 57       57     46.6    2.2969    5.5166
#> experimental_condition=21 56       56     59.2    0.1755    0.3878
#> experimental_condition=22 61       60     65.4    0.4450    1.0120
#> 
#>  Chisq= 5.7  on 3 degrees of freedom, p= 0.1 
get_survdiff(kpm_est$d, "experimental_condition", 1)
#> Call:
#> survdiff(formula = f, data = kds, rho = test_type)
#> 
#>                            N Observed Expected (O-E)^2/E (O-E)^2/V
#> experimental_condition=11 72     50.4     50.0   0.00318    0.0122
#> experimental_condition=12 57     45.2     38.0   1.35827    4.7009
#> experimental_condition=21 56     37.4     39.4   0.10730    0.3805
#> experimental_condition=22 61     37.8     43.4   0.70499    2.5778
#> 
#>  Chisq= 5.9  on 3 degrees of freedom, p= 0.1