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Calibrate two-belt respiratory inductance plethysmography

Source: R/resp.R
ripCalibrate.Rd

Fits the Konno-Mead two-degree-of-freedom volume model from ribcage and abdominal belt signals. Least-squares calibration uses a reference volume trace; qualitative diagnostic calibration (QDC) equalizes the variability of the two belt contributions.

Usage

ripCalibrate(
  rc,
  ab,
  reference = NULL,
  sr = NULL,
  method = c("qdc", "lsq"),
  band = c(0.1, 0.6),
  window = NULL,
  fit_intercept = FALSE,
  known_volume = NULL
)

Arguments

rc

Ribcage signal as a numeric vector, or a PhysioExperiment.

ab

Abdominal numeric vector, or a channel index/label when rc is a PhysioExperiment.

reference

Optional reference volume signal, required for "lsq".

sr

Sampling rate in Hz for numeric signals. A PhysioExperiment supplies its own sampling rate.

method

Calibration method, "qdc" or "lsq".

band

Two-element respiratory band in Hz.

window

Optional inclusive calibration sample range c(lo, hi).

fit_intercept

Logical; include an intercept in least squares.

known_volume

Optional known inspiratory volume used for absolute scaling.

Value

A rip_calibration object containing coefficients, calibration diagnostics, and the calibrated volume-proportional signal.

References

Konno K, Mead J (1967). Measurement of the separate volume changes of rib cage and abdomen during breathing. Journal of Applied Physiology, 22:407-422.

Sackner MA, Watson H, Belsito AS, et al. (1989). Calibration of respiratory inductive plethysmograph during natural breathing. Journal of Applied Physiology, 66:410-420. doi:10.1152/jappl.1989.66.1.410

Examples

sr <- 10
time <- (0:599) / sr
rc <- 2 * sin(2 * pi * 0.25 * time)
ab <- sin(2 * pi * 0.25 * time)
ripCalibrate(rc, ab, sr = sr)
#> <rip_calibration> method=qdc, sr=10 Hz
#>   coefficients: RC=1, AB=2  K=2  scale=1