A Demonstration ofLackofVariability among SixTuberculin SkinTestReaders

Thevariability oftuberculin skin testreadings among sixtrained andexperienced readers wasevaluated using amodified sliding caliper method. Eachof537tests werereadindependently by tworeaders. Therewere23disagreements between paired readers resulting inanoverall interobserver reliability of95.7 percent. In82 percentofthepaired readings theresults weredifferent by2mm or less. Theobserver lack ofvariability waslikely duetothetraining andexperience ofthereaders. (AmJ Public Health1985; 75:1341-1343.)