Non-invasive tear film break-up time: sensitivity and specificity.

The accuracy of a diagnostic technique; non-invasive tear film break-up time (NIBUT) was determined by calculating the sensitivity and specificity of the test. Thirty-three dry eye patients (65 eyes) of varying severity (mild, moderate and severe) and 66 age and sex matched normal subjects (132 eyes) were examined. The results indicate that the critical value of 10 seconds for the NIBUT provides sensitivity of 82% and specificity of 86%.