If you do multiple tests in quick succession, the moisture on the sensor can skew results. We recommend leaving at least 15 minutes between breath tests, and taking no more than 12 tests during a regular day and 20 tests during a day when you're doing a Food Challenge.
For more on how often you should be testing, please see our FAQ on this issue.
It's also important to use a consistent breath test technique for accurate results. For more information on breath test technique, see our FAQ answer.
Finally, the fermentation levels in your gut naturally fluctuate as you go through your day so if you do a test every few minutes, it very well can be the result of the foods being fermented as you are testing.