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Calculate Normalized Width for Effect Concentration Estimates

Source: R/drc_Helper.R
calcNW.Rd

Calculates the normalized width of confidence intervals for effect concentration (EC) estimates by dividing the interval width by the estimate value. Also provides a rating for the calculated normalized width.

Usage

calcNW(x, ED = "ZG")

Arguments

x

A data frame containing EC estimates, typically output from ED function. Must contain columns 'Upper', 'Lower', and 'Estimate'.

ED

Character string indicating the source of EC estimates. Must be either "ZG" (default) or "drc".

Value

A data frame with two columns:

  • NW: Normalized width calculated as (Upper - Lower) / Estimate

  • Rating: Categorical rating of the normalized width

Row names are preserved from input for "ZG" or modified to "EC_x" format for "drc".

See also

ECx_rating for the rating system used

Examples

# Example with ZG format
ec_data <- data.frame(
  Lower = c(1.2, 2.3),
  Upper = c(1.8, 3.1),
  Estimate = c(1.5, 2.7),
  row.names = c("EC10", "EC50")
)
calcNW(ec_data, ED = "ZG")
#>             NW Rating
#> EC10 0.4000000   Good
#> EC50 0.2962963   Good

# Example with drc format
drc_data <- data.frame(
  Lower = c(1.2, 2.3),
  Upper = c(1.8, 3.1),
  Estimate = c(1.5, 2.7),
  row.names = c("Dose:1:10", "Dose:1:50")
)
calcNW(drc_data, ED = "drc")
#>              NW Rating
#> EC_10 0.4000000   Good
#> EC_50 0.2962963   Good