The problem with all tests is that they take a snapshot view of a complex situation, and try to evaluate that as a simple, precise number. We then try to interpret that number as if it is a pass or a fail.
It would be better if these tests reported a range of likely probabilities, say “between 8 and 10″ rather than 8.8. Certainly interpretation of the average, against expectations from treatment being taken, makes more sense.
As zip2play reports, professional uric acid tests are not faultless, but they are rarely questioned. I have experienced nonsensical professional blood pressure tests. Even the “dead or alive” test has been fooled by Lazarus Syndrome. In fact many tests results are difficult to reproduce – one wonders how professionals would fare if retaking the tests that gave them their qualifications.
So where does all that testing doubt leave us?
For anyone who is getting proper uric acid control from their doctors, I cannot see the point of home testing. Each doctor will have their own specific regime, but the general approach is quite clear.
Titration phase involves gradually increasing dose of an appropriate medication with the most frequent uric acid monitoring. Once two consecutive results have hit under 6mg/dL, we move to the next phase.
Urate reduction phase involves less frequent monitoring to ensure that levels remain below 6mg/dL. It continues until there has been 6 months without a gout flare, when we start the final phase.
Maintenance phase involves the least frequent monitoring to ensure that levels remain below 6.5mg/dL. If dosage is reduced at all during this phase, it should be done gradually, accompanied with more frequent testing. In effect, a reverse titration phase.
With that level of professional medical support, any test-to-test fluctuations can be managed by dose adjustment or “wait until the next test”. The main focus is on the general trend, supported by continuous care.
Where that level of professional support is unavailable, then gout sufferers might consider home testing, but this is always likely to be less effective than good professional monitoring.
Fundamentally, there is less reliability from a pin prick blood drop (from the capillaries) compared with “an armful” (from the the vein). However, studies have shown there to be sufficient correlation to make the test meaningful. Interpretation has to reflect a wider margin of error. And correlation with symptoms is also important.
What you are really looking for is a reducing average trend. You might consider a lower target than 6mg/dL to allow for the inherent reliability issues – i.e. interpret a reading of 6mg/dL to be a range of 4.5 to 7.5. If a lowering trend is accompanied by gout flares that reduce in intensity and frequency, then you know you are on the right track. When the gout flares have gone for 6 months, then you know you have achieved your goal.
So a home test is only relevant if it ties in with your own long term plan to lower uric acid to the point that it no longer affects your enjoyment of life. Use it if you want to, but focus on trends reflected in your own condition – not absolute numbers. Also focus on a strictly repetitive testing regime to minimize procedural variances (I’ve covered this elsewhere, and will summarize all this soon).