The 95% limits of agreement approach still works when one method of measurement is a "gold standard". It tells us how far from the "gold standard" the measurements by the new method are likely to be.
The limits of agreement approach is symmetrical, in that it does not make either method the standard, but it works just as well when there is a direction to the difference. Calculating differences as "new method" minus "gold standard" would be best, as you would then be able to say that the new method might exceed the "gold standard" by up to the upper 95% limit and be less than the "gold standard" by up to the lower 95% limit.
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Last updated: 12 January, 2004.
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