plausibility_methods

checkVA

checkVA.quali

checkVA.snellen

checkVA.snellendec

checkVA.logmar

checkVA.etdrs

checkVA.default

further arguments passed to methods

S3 methods for checking plausibility of VA entries

internal

There is no ophthalmic researcher who has not had headaches from
the handling of visual acuity entries. Different notations, untidy entries.
This shall now be a matter of the past. Eye makes it as easy as pie to work
with VA data - easy cleaning, easy conversion between
Snellen, logMAR, ETDRS letters, and qualitative visual acuity
shall never pester you again. The eye
package automates the pesky task to count number of patients and eyes,
and can help to clean data with easy re-coding for right and left eyes.
It also contains functions to help reshaping eye side specific variables
between wide and long format. Visual acuity conversion is based on
Schulze-Bonsel et al. (2006) <doi:10.1167/iovs.05-0981>,
Gregori et al. (2010) <doi:10.1097/iae.0b013e3181d87e04>,
Beck et al. (2003) <doi:10.1016/s0002-9394(02)01825-1> and
Bach (2007) <http:michaelbach.de/sci/acuity.html>.

Tjebo Heeren

Analysis of Eye Data

Antoine Fabri

plausibility_methods function

<dl><dt>x</dt>
<dd>vector of visual acuities</dd>
<dt>...</dt>
<dd>further arguments passed to methods</dd></dl>

Arguments

VA can be snellen (fraction: feet/meter), snellen decimal, logMAR, ETDRS, or
"qualitative" (Counting fingers, etc.)<ul>
<li>Snellen fractions need to be either form 6/x or 20/x</li>
<li>Snellen decimal must be &gt; 0 and &lt;= 2</li>
<li>ETDRS must be &gt;= 0 and &lt;= 100</li>
<li>logMAR must be &gt;= -0.3 and &lt;= 3.0</li>
<li>Qualitative must be PL, LP, NLP, NPL, HM, CF (any case allowed)</li>
</ul>Any element which is implausible / not recognized will be converted to NA

Plausibility checks

Plausibility checking — plausibility_methods

<dl>

<dt>x</dt>
<dd>vector of visual acuities</dd>


<dt>...</dt>
<dd>further arguments passed to methods</dd>

</dl>

VA can be snellen (fraction: feet/meter), snellen decimal, logMAR, ETDRS, or
"qualitative" (Counting fingers, etc.)<ul>
<li>Snellen fractions need to be either form 6/x or 20/x</li>
<li>Snellen decimal must be &gt; 0 and &lt;= 2</li>
<li>ETDRS must be &gt;= 0 and &lt;= 100</li>
<li>logMAR must be &gt;= -0.3 and &lt;= 3.0</li>
<li>Qualitative must be PL, LP, NLP, NPL, HM, CF (any case allowed)</li>
</ul>

Any element which is implausible / not recognized will be converted to NA

plausibility_methods: Plausibility checking

Description

Usage

Value

Arguments

Plausibility checks

See Also