Generates a vitamin D status profile curve for each individual in a group
vitd.curve( n = 1, type = c("placebo","fixed-dose","dynamic-dose"), start = 0, end = 1,
mu = 45, amplitude = 35, dyn.dose.thresh = 50, sd.mu = 5, sd.amplitude = 5,
sd.dyn.dose.thresh = 5, supp.dose = 20, supp.dose.rate = Inf, weight = 1,
sd.weight = 0, min.thresh = 10, north.hemi = TRUE, res = 40 )vitd.curve returns an object of class vitd.curve. Curve parameter settings are returned. The slot curves give the curve specific parameters for each of the n generated curves. Additionally, time used for plotting gives time values passed to plot.vitd.curve.
Number of curves to simulate.
One of "placebo", "fixed-dose", "dynamic-dose".
Time in units of years when trial started.
Time in units of years when trial ended.
The mean level of 25OHD in the trial arm around which there is cosine variation.
Amplitude of cosine function describing variation around mu
Threshold for the concentration-controlled scheme.
Standard deviation levels around mean; this is the standard deviation of H in vignette.
Standard deviation of the amplitude.
Standard deviation of the participant retained concentration in the concentration-controlled trial.
The 25OHD nmol/l equivalent for dosage in fixed-dose supplementation.
Concentration parameter for fixed-dose scheme uptake. Large values imply that all participants derive the same equivalent.
For fixed-dose supplementation, this is the expected value of the proportion of the dose which is always utilized.
Standard deviation of weight
The minimum detectable threshold of 25OHD. Defaults to 10 nmol/l.
Summer/winter months as in the Northern Hemisphere if TRUE and Southern Hemisphere if FALSE.
Resolution parameter for plotting of vitamin D curves.
Rebecca Mangan and Jason Wyse