General Sources of Error with Reagent Strip
Testing
Urinalysis and Body
Fluids Review 492
POSSIBLE EFFECT COMMENTS
Failure to test within 2 hr of collection
or to preserve correctly
Failure to bring refrigerated specimens
to RT before testing
Failure to mix specimen well
Failure to follow manufacturer’s
instructions
Failure to dip all test pads in urine
Prolonged dipping
Failure to remove excess urine from strip
Failure to read at recommended time
Failure to compare to color chart or
read in good light
Failure to store strips properly
WBCs, RBCs settle out.
Reagents may leach from pads.
Store in capped original container at RT.
Changes in chemical composition
False-neg enzymatic rxns
False-neg leukocyte, blood
Erroneous results
False-neg rxns
False-neg rxns
Runover of chemicals to adjacent
pads, distortion of colors
Erroneous results
Erroneous results
Erroneous results
continued...
