Compute Concentration for Upper Prediction — compute_conc_for_upper

Computes the concentration needed for an upper conf_int prediction of the threshold value.

Usage

compute_conc_for_upper_pred(
  data,
  fit,
  conc_col_name,
  trt_col_name = NULL,
  treatment_group = NULL,
  threshold = 10,
  conf_int = 0.9
)

Arguments

data: A data frame containing C-QT analysis dataset
fit: An nlme::lme model object from model fitting
conc_col_name: String of concentration (independent variable) column name
trt_col_name: String of treatment group column name (optional, NULL for models without treatment)
treatment_group: String of treatment group to make prediction for (optional, NULL for models without treatment)
threshold: Value used as upper CI prediction, default = 10
conf_int: Numeric confidence interval level (default: 0.9)

Value

Single numeric concentration value where upper CI crosses threshold. Returns NA with warning if no positive concentration is found.

Examples

mod <- fit_prespecified_model(
  cqtkit_data_verapamil %>% preprocess(),
  deltaQTCF,
  ID,
  CONC,
  deltaQTCFBL,
  TRTG,
  TAFD,
  "REML",
  remove_conc_iiv = TRUE
)
compute_conc_for_upper_pred(
  cqtkit_data_verapamil %>% preprocess(),
  mod,
  "CONC",
  "TRTG",
  "Verapamil HCL"
)
#> [1] 362.0367