coef_by_group {breathtestcore}

Tabulates per-group breath test parameters

Description

Given a fit to 13C breath test curves, computes absolute values and their confidence intervals of parameters, e.g. of the half emptying time t50. Generic S3 method for class breathtestfit.

Usage

coef_by_group(fit, ...)

Arguments

fit

Object of class breathtestfit, for example from nlme_fit, nls_fit or stan_fit

...

Not used

Value

A tibble of class coef_by_group with columns

parameter

Parameter of fit, e.g. beta, k, m, t50

method

Method used to compute parameter. exp_beta refers to primary fit parameters beta, k, m. maes_ghoos uses the method from Maes B D, Ghoos Y F, Rutgeerts P J, Hiele M I, Geypens B and Vantrappen G 1994 Dig. Dis. Sci. 39 S104-6. bluck_coward is the self-correcting method from Bluck L J C and Coward W A 2006

group

Grouping parameter of the fit, e.g. patient, normal, liquid, solid

estimate

Parameter estimate

conf.low, conf.high

Lower and upper 95 estimate.

diff_group

Letters a, b, c indicate that parameter would be in mutually significantly different groups. Letter combinations like ab or abc indicated that this parameter is not significantly different from the given other groups in a Tukey-corrected pairwise test.

Examples

library(dplyr)
data("usz_13c")
data = usz_13c %>%
  dplyr::filter( patient_id %in%
    c("norm_001", "norm_002", "norm_003", "norm_004", "pat_001", "pat_002","pat_003")) %>%
  cleanup_data()
fit = nls_fit(data)
coef_by_group(fit)

fit = nlme_fit(data)
coef_by_group(fit)