ds.getWGSR.RdCalculate WHO Growth Reference z-score for a given anthropometric measurement
This function is similar to R function getWGSR from the zscorer package.
ds.getWGSR(
sex = NULL,
firstPart = NULL,
secondPart = NULL,
index = NULL,
standing = NA,
thirdPart = NA,
newobj = NULL,
datasources = NULL
)the name of the binary variable that indicates the sex of the subject. This must
be coded as 1 = male and 2 = female. If in your project the variable sex has different
levels, you should recode the levels to 1 for males and 2 for females using the
ds.recodeValues DataSHIELD function before the use of the ds.getWGSR.
Name of variable specifying:
Weight (kg) for BMI/A, W/A, W/H, or W/L
Head circumference (cm) for HC/A
Height (cm) for H/A
Length (cm) for L/A
MUAC (cm) for MUAC/A
Sub-scapular skinfold (mm) for SSF/A
Triceps skinfold (mm) for TSF/A
Give a quoted variable name as in (e.g.) "weight". Be careful with units (weight in kg;
height, length, head circumference, and MUAC in cm; skinfolds in mm).
Name of variable specifying:
Age (days) for H/A, HC/A, L/A, MUAC/A, SSF/A, or TSF/A
Height (cm) for BMI/A, or W/H
Length (cm) for W/L
Give a quoted variable name as in (e.g.) "age". Be careful with units (age in days;
height and length in cm).
The index to be calculated and added to data. One of:
bfa BMI for age
hca Head circumference for age
hfa Height for age
lfa Length for age
mfa MUAC for age
ssa Sub-scapular skinfold for age
tsa Triceps skinfold for age
wfa Weight for age
wfh Weight for height
wfl Weight for length
Give a quoted index name as in (e.g.) "wfh".
Variable specifying how stature was measured. If NA (default) then age (for "hfa" or "lfa") or height rules (for "wfh" or "wfl") will be applied. This must be coded as 1 = Standing; 2 = Supine; 3 = Unknown. Missing values will be recoded to 3 = Unknown. Give a single value (e.g."1"). If no value is specified then height and age rules will be applied.
Name of variable specifying age (in days) for BMI/A. Give a quoted variable
name as in (e.g.) "age". Be careful with units (age in days). If age is given in different units
you should convert it in age in days using the ds.make DataSHIELD function before the use
of the ds.getWGSR. For example if age is given in months then the transformation is given
by the formula $age_days=age_months*(365.25/12)$.
a character string that provides the name for the output variable
that is stored on the data servers. Defaults getWGSR.newobj.
a list of DSConnection-class objects obtained after login.
If the datasources argument is not specified the default set of connections will be
used: see datashield.connections_default.
ds.getWGSR assigns a vector for each study that includes the z-scores for the
specified index. The created vectors are stored in the servers.
The function calls the server-side function getWGSRDS that computes the WHO
Growth Reference z-scores of anthropometric data for weight, height or length, MUAC (middle
upper arm circumference), head circumference, sub-scapular skinfold and triceps skinfold.
Note that the function might fail or return NAs when the variables are outside the ranges
given in the WGS (WHO Child Growth Standards) reference (i.e. 45 to 120 cm for height and
0 to 60 months for age). It is up to the user to check the ranges and the units of their
data.
if (FALSE) { # \dontrun{
# Connecting to the Opal servers
require('DSI')
require('DSOpal')
require('dsBaseClient')
builder <- DSI::newDSLoginBuilder()
builder$append(server = "study1",
url = "http://192.168.56.100:8080/",
user = "administrator", password = "datashield_test&",
table = "ANTHRO.anthro1", driver = "OpalDriver")
builder$append(server = "study2",
url = "http://192.168.56.100:8080/",
user = "administrator", password = "datashield_test&",
table = "ANTHRO.anthro2", driver = "OpalDriver")
builder$append(server = "study3",
url = "http://192.168.56.100:8080/",
user = "administrator", password = "datashield_test&",
table = "ANTHRO.anthro3", driver = "OpalDriver")
logindata <- builder$build()
# Log onto the remote Opal training servers
connections <- DSI::datashield.login(logins = logindata, assign = TRUE, symbol = "D")
# Example 1: Generate the weight-for-height (wfh) index
ds.getWGSR(sex = "D$sex", firstPart = "D$weight", secondPart = "D$height",
index = "wfh", newobj = "wfh_index", datasources = connections)
# Example 2: Generate the BMI for age (bfa) index
ds.getWGSR(sex = "D$sex", firstPart = "D$weight", secondPart = "D$height",
index = "bfa", thirdPart = "D$age", newobj = "bfa_index", datasources = connections)
# clear the Datashield R sessions and logout
datashield.logout(connections)
} # }