Concordance Computes concordance and casewise concordance

Concordance for Twins

Usage

concordanceCor(
  object,
  cif1,
  cif2 = NULL,
  messages = TRUE,
  model = NULL,
  coefs = NULL,
  ...
)

Arguments

object: Output from the cor.cif, rr.cif or or.cif function
cif1: Marginal cumulative incidence
cif2: Marginal cumulative incidence of other cause (cause2) if it is different from cause1
messages: To print messages
model: Specfifies wich model that is considered if object not given.
coefs: Specfifies dependence parameters if object is not given.
...: Extra arguments, not used.

Details

The concordance is the probability that both twins have experienced the event of interest and is defined as $$ cor(t) = P(T_1 \leq t, \epsilon_1 =1 , T_2 \leq t, \epsilon_2=1) $$

Similarly, the casewise concordance is $$ casewise(t) = \frac{cor(t)}{P(T_1 \leq t, \epsilon_1=1) } $$ that is the probability that twin "2" has the event given that twins "1" has.

References

Estimating twin concordance for bivariate competing risks twin data Thomas H. Scheike, Klaus K. Holst and Jacob B. Hjelmborg, Statistics in Medicine 2014, 1193-1204

Estimating Twin Pair Concordance for Age of Onset. Thomas H. Scheike, Jacob V B Hjelmborg, Klaus K. Holst, 2015 in Behavior genetics DOI:10.1007/s10519-015-9729-3

Author

Thomas Scheike