Calculates Z-Scores based on data
Arguments
- .data
data object
- round
round output to how many decimal place description
- na.rm
remove NA values before calculating z-scores
- Xi
physical measurement (e.g. weight, length, head circumference, stature or calculated BMI value)
- Mi
values from the table (see reference) corresponding to the age in months of the child
- Si
values from the table (see reference) corresponding to the age in months of the child
- Li
values from the table (see reference) corresponding to the age in months of the child
References
CDC growth chart Z score calculation: https://www.cdc.gov/growthcharts/cdc-data-files.htm
Examples
# Capture z-score from the following distribution x
x = c(6, 7, 7, 12, 13, 13, 15, 16, 19, 22)
z_scores = zscore(x, round = 2) # limit to 2 decimal place
z_scores = zscore(x) # no decimal place limit
df = data.frame(val = x, zscore = z_scores)
head(df)
#> val zscore
#> 1 6 -1.3228757
#> 2 7 -1.1338934
#> 3 7 -1.1338934
#> 4 12 -0.1889822
#> 5 13 0.0000000
#> 6 13 0.0000000
#EXAMPLE for zscore based on CDC growth chart
# Calculate the zscore for a patient weighing 50kg
Li=-0.1600954
Mi=9.476500305
Si=0.11218624
Xi=50
zscoreGrowthCurve(Xi,Mi,Si,Li)
#> [1] 13.01574