CVwR from the upper expanded limit (ABEL)

Calculates the intra-subject CV (coefficient of variation) of the reference from the upper expanded limit of a BE study (replicate design for ABEL). Useful if no CV_wR but the expanded limits were given.

CVwRfromU(U, regulator = "EMA")
U2CVwR(U, regulator = "EMA")

Arguments

U

Upper expanded limit.
Must be within {1.2500, 1.4319} if regulator="EMA" and within {1.2500, 1.5000} if regulator="HC".

regulator

Regulatory body’s settings for expanding the BE acceptance limits, given as a string from the choices "EMA" or "HC". Defaults to regulator="EMA".

Details

Only the upper expanded limit is supported since it offers one more significant digit than the lower expanded limit.

Value

Numeric value of the CVwR as ratio, where CVwR = sqrt(exp((log(U)/r_const)^2)-1).

Note

U2CVwR() is simply an alias to CVwRfromU().

Author

H. Schütz

Examples

# Given the upper expanded limit and using the defaults
CVwRfromU(U = 1.38)
#> [1] 0.44355
# should give [1] 0.44355, i.e., a CVwR ~ 44%
# Upper limit from a study according the Health Canada’s rules
CVwRfromU(U = 1.48, regulator = "HC")
#> [1] 0.55214
# should give [1] 0.55214