Snellen chart H, K, O, S, 3, U, Y, A, C, E, G, L, 2. The normal Snellen chart is printed with eleven lines of block letters. The first line consists of one very large letter, which may be one of several letters, for example E, H, or N. Subsequent rows have increasing numbers of letters that decrease in size. A person taking the test covers one eye from 6 metres or 20 feet away, and reads aloud the letters of each row, beginning at the top. The smallest row that can be read accurately indicates the visual acuity in that specific
Clinical urine tests Clinical urine tests Clinical urine tests are various tests of urine for diagnostic purposes. The most common is a urinalysis (UA), one of the most common methods of medical diagnosis. The word is a portmanteau of the words "urine" and "analysis". Other tests are urine culture (a microbiological culture of urine) and urine electrolyte levels. The target parameters that can be measured or quantified in urinalysis include naked-eye (gross) examination for color and smell plus analysis for many substances and cells, as well as other properties, such as specific gravity. A part of a urinalysis can be performed by using