Concordance for Twins

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