How do these things work?

are you asking about use of the Snellen chart?

the person is positioned exactly 20 feet from the chart then uses an opaque card to shield one eye at a time during the test

the person can wear contact lenses or glasses during the test

the person reads through the chart to the smallest line of letters possible

then record the result using the numeric fraction at the end of the last successful line read (indicate whether or not the person missed any letters or if corrective lenses were worn -- for eg. "O.D. 20/30 --1, with glasses"

On the scale, to do it "by the book" you should zero the scale and have it at zero when the pt steps on to it. Then move the large weight one notch at a time until it's tipped too far, then move it back one. Then focus on the small weight until it's balanced.

On height, yes, use the number at the gatch. As you found out, the top number never changes. :)

are you asking about use of the Snellen chart?

the person is positioned exactly 20 feet from the chart then uses an opaque card to shield one eye at a time during the test

the person can wear contact lenses or glasses during the test

the person reads through the chart to the smallest line of letters possible

then record the result using the numeric fraction at the end of the last successful line read (indicate whether or not the person missed any letters or if corrective lenses were worn -- for eg. "O.D. 20/30 --1, with glasses"

Maybe I am using a different chart, but on the one I am using , there are *two* sets of numbers, one on the right of the series of letters, and one at the left , both are different, so which one do we record?