Pad-weighing tests in the diagnosis and quantification of incontinence

Abstract

Pad tests for assessing urinary incontinence have existed for over 20 years, but have recently been subject to scientific scrutiny. Essentially there are two types of tests, those carried out in the laboratory or office and those done at home. The principal issues are those of accuracy and validity, the latter usually being a question of reproducibility. The laboratory tests last for 1 or 2 hours, have precisely defined exercise regimens and documented normal loss rates of less than 2 g/h. For the tests where bladder volume is regulated, reproducibility is better but the tests are more invasive. These office tests have a high predictive value positive but do suffer from an excessive false negative rate. Home pad tests, on the other hand are less regulated, last for 24 or 48 hours and have normal loss rates of less than 8 g/24 h. They have a better predictive value negative and an equivalent predictive value positive and so are probably superior in terms of their reproducibility. Pad tests have their limitations but should be regarded as a valuable component of the urodynamic armamentarium.