fam.recrisk {fam.recrisk}

Familial risk of recurrent disease

Description

Given vectors of family sizes and number of affecteds per family, calculates the risk of disease recurrence

Usage

fam.recrisk(s, a, k)

Arguments

s

vector of sizes of families

a

vector of number of affected members per family; same length as vector s

k

number of affecteds to condition on; the ascertainment criterion, e.g., at least k affecteds

Details

Estimate risk of disease for a person with at least k affected relatives, where k can be specified in order to determine how risk varies with k. Estimates are based on a truncated binomial distribution where families with less than k affected relatives are truncated from the sample. If the sample of families in not a random sample from a population, the prevalence will be biased, and merely represent the frequency of disease in the sample.

Value

A list with the following values

phat

disease recurrence risk

prev

estimate of disease prevalence

var.phat

variance of phat

var.prev

variance of prev

covar

covariance between phat and prev

Author(s)

Schaid DJ, Sinnwell JP.

References

Schaid DJ, McDonnell SK, Thibodeau SN. Familial recurrence risk with varying amount of family history. Under review at Genetic Epidemiology, 2018.

Examples

s <- c(4,  8,  6,  6,  10, 8,  7,  8,  5,  6,  10, 4,  4,  8,  6,  8,  4,  5,  9, 
       9,  5,  4,  4,  7,  3,  3,  9,  5,  3,  3,  4,  6,  8,  3,  5,  8,  6,  8, 9,  3)

a <- c(3, 4, 2, 5, 4, 5, 3, 4, 3, 3, 8, 2, 0, 3, 4, 5, 2, 3, 4, 2, 1, 1,
       1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 1, 0, 2, 3, 0)
fam.recrisk(s,a,1)