pd: Integrated Event Probability Over an Interval

In lrstat: Power and Sample Size Calculation for Non-Proportional Hazards and Beyond

Integrated Event Probability Over an Interval

Description

Obtains the integration of the probability of having an event during an interval. The specified analysis time interval can span more than one analysis time interval with constant hazard.

Usage

pd(
  t1 = NA_real_,
  t2 = NA_real_,
  piecewiseSurvivalTime = 0L,
  lambda = NA_real_,
  gamma = 0L
)

Arguments

t1	Lower bound of the analysis time interval.
t2	Upper bound of the analysis time interval.
piecewiseSurvivalTime	A vector that specifies the starting time of piecewise exponential survival time intervals. Must start with 0, e.g., c(0, 6) breaks the time axis into 2 event intervals: [0, 6) and [6, Inf). Defaults to 0 for exponential distribution.
lambda	A vector of hazard rates for the event. One for each analysis time interval.
gamma	The hazard rate for exponential dropout, or a vector of hazard rates for piecewise exponential dropout.

Value

A value for the integrated probability of having an event during an interval for a treatment group with specified piecewise exponential survival and dropout distributions.

Author(s)

Kaifeng Lu, [e-mail]

Examples

# Piecewise exponential survival with hazard 0.0533 in the first 6
# months, and hazard 0.0309 thereafter, and 5% dropout by the end of
# 1 year.

pd(t1 = 1, t2 = 8, piecewiseSurvivalTime = c(0, 6),
   lambda = c(0.0533, 0.0309), gamma = -log(1-0.05)/12)

lrstat documentation built on Oct. 18, 2024, 9:06 a.m.