S3 methods for checking plausibility of VA entries
checkVA(x, ...)# S3 method for quali
checkVA(x, ...)
# S3 method for snellen
checkVA(x, ...)
# S3 method for snellendec
checkVA(x, ...)
# S3 method for logmar
checkVA(x, ...)
# S3 method for etdrs
checkVA(x, ...)
# S3 method for default
checkVA(x, ...)
vector of visual acuities
further arguments passed to methods
vector with visual acuity of class va. See also "VA classes"
VA can be snellen (fraction: feet/meter), snellen decimal, logMAR, ETDRS, or "qualitative" (Counting fingers, etc.)
Snellen fractions need to be either form 6/x or 20/x
Snellen decimal must be > 0 and <= 2
ETDRS must be >= 0 and <= 100
logMAR must be >= -0.3 and <= 3.0
Qualitative must be PL, LP, NLP, NPL, HM, CF (any case allowed)
Any element which is implausible / not recognized will be converted to NA
Other VA converter:
VAwrapper,
snellen_steps,
va_methods,
va_mixed(),
va(),
which_va()