Compute follow-up overlap with an attained-age band

Computes the amount of follow-up time contributed within a single attained-age band.

Usage

.overlap_weight(band_lower_age, band_upper_age, entry_age, exit_age)

Arguments

band_lower_age

Numeric scalar or vector giving the lower boundary of the attained-age band.

band_upper_age

Numeric scalar or vector giving the upper boundary of the attained-age band.

entry_age

Numeric scalar or vector giving age at entry.

exit_age

Numeric scalar or vector giving age at exit (event or censoring).

Value

Numeric scalar or vector giving the overlap duration. Returns 0 where the intervals do not intersect.

Details

Specifically, this function returns the length of the intersection between the subject's follow-up interval [entry_age, exit_age) and the attained-age band [band_lower_age, band_upper_age).

All intervals are treated as left-closed, right-open.

Examples

.overlap_weight(
  band_lower_age = 50,
  band_upper_age = 60,
  entry_age = 55,
  exit_age = 65
)
#> Error in .overlap_weight(band_lower_age = 50, band_upper_age = 60, entry_age = 55,     exit_age = 65): could not find function ".overlap_weight"