Specific gravity (SG) measured with the chemical reagent strip method correlates well with gravimetric measurement, and, unlike the gravimetric or refractometer methods, does not need to be corrected for glucose or protein. Cloudy/turbid urines do not need to be clarified before measuring specific gravity with the reagent strip method. It is the recommended method for determining specific gravity if a urine specimen contains x-ray contrast media or plasma expanders.
Alkaline urine can affect the indicator system and lower the specific gravity result on the reagent pad. If the result is being read visually, it is recommended that .005 be added to the specific gravity result when the pH is alkaline. Most chemical reagent strip readers, however, will automatically adjust the specific gravity reading for pH.
A specific gravity reading higher than the chemical reagent strip range would need to be measured by another method, and may require dilution.