None of the parameters changed color, is that considered an invalid test?

If none of the reagent pads on your urine test strip change color, it does not necessarily indicate an invalid test. In fact, this scenario is quite common and generally means that the test has yielded a negative result for all the parameters being measured.

However, it's essential to ensure that all pads on the test strip were thoroughly wet with urine. Insufficient contact between the urine and the reagent pads can prevent color changes, potentially leading to misleading results. Double-check that the strip was properly immersed in the urine sample and that it remained in contact with the urine for the appropriate amount of time as specified in the test instructions.

If you followed the instructions correctly and still observe no color change, it is typically interpreted as a negative result for all tested parameters. If you have any concerns or doubts about the test, it may be helpful to repeat the test with a new strip or consult with a healthcare professional for further advice.