Evidence based guidelines for the performance of the sweat test for the investigation of cystic fibrosis in the UK.

A well produced evidence based guideline has been developed in response to a national audit that demonstrated wide variations in the performance of sweat tests. Accurate and reliable sweat test results will be particularly important with the advent of neonatal screening. The guideline recommendations include the collection and analysis of sweat samples, and interpretation of results. It emphasises the importance of sweat chloride as the best discriminator.