The reliability of a chemical test for haematuria has been evaluated in patients referred for investigation of suspected renal or urological disease. Red blood cells in concentrations of 10/microliter or greater were found in 24% of urines giving a negative dipstick result, 82% of urines giving a trace positive result and nearly 100% of urines giving dipstick results greater than this. The accuracy of the reagent strip in predicting the presence or absence of significant haematuria was improved by testing several urines from each patient. On the basis of this study, if significant haematuria is present, reagent strip urine testing is an efficient method for its detection.

In an evaluation of a chemical test for haematuria, all patients with positive results or a history of frank haematuria were investigated to determine the source of bleeding. In 10 of the 92 patients in whom the diagnosis was unknown at the time of admission, the presence of haematuria could not be confirmed. Of the remaining 82 patients urinary tract pathology was identified in 74. Of the other eight patients, four had exercise-induced haematuria with no other indications of significant pathology, and in four patients investigations stopped short of renal biopsy because of the patients' age.