Maybe I'm reading the news story incorrectly, but aren't they saying they discontinued sweat tests at that hopsital because that particular hospital was not doing the test correctly and thus they were producing inacurrate results. Not that sweat tests are globally inaccurate. From the story: "While some borderline cases slip through the net, Libby's salt levels were far higher than the level associated with the condition and shouldn't have been missed."I think it's a different argument that people with low sweats can still have CF, which we have all see happen, but in this case if the sweat test had been administered by a trained professional the child would have been told she had CF because she had an obviously positive test result.