title: Creation and validation of a visual macroscopic hematuria scale for optimal communication and an objective hematuria index.
abstract: OBJECTIVE
  Macroscopic hematuria is a common symptom and sign that is challenging to quantify and describe. The degree of hematuria communicated is variable due to health worker experience combined with lack of a reliable grading tool. We produced a reliable, standardized visual scale to describe hematuria severity. Our secondary aim was to validate a new laboratory test to quantify hemoglobin in hematuria specimens.
  
  
  METHODS
  Nurses were surveyed to ascertain current hematuria descriptions. Blood and urine were titrated at varying concentrations and digitally photographed in catheter bag tubing. Photos were processed and printed on transparency paper to create a prototype swatch or card showing light, medium, heavy and old hematuria. Using the swatch 60 samples were rated by nurses and laymen. Interobserver variability was reported using the generalized kappa coefficient of agreement. Specimens were analyzed for hemolysis by measuring optical density at oxyhemoglobin absorption peaks.
  
  
  RESULTS
  Interobserver agreement between nurses and laymen was good (kappa = 0.51, p <0.001). Subgroup analysis showed substantial agreement for light hematuria (kappa = 0.71). Overall agreement improved when the moderate (kappa = 0.28) and heavy (kappa = 0.53) hematuria categories were combined (kappa = 0.70). Compared to known blood concentrations the assay of optical density at oxyhemoglobin absorption peaks showed a linear trend.
  
  
  CONCLUSIONS
  A simple visual scale to grade and communicate hematuria with adequate interobserver agreement is feasible. The test for optical density at oxyhemoglobin absorption peaks is a new method, validated in our study, to quantify hemoglobin in a hematuria specimen.
authors.affiliation: Department of Urology, Western Health, Victoria, Australia. lihmingwong@gmail.com
authors.forename: Lih-Ming
authors.initials: LM
authors.lastname: Wong
authors.forename: Jia-Min
authors.initials: JM
authors.lastname: Chum
authors.forename: Peter
authors.initials: P
authors.lastname: Maddy
authors.forename: Steven T F
authors.initials: ST
authors.lastname: Chan
authors.forename: Douglas
authors.initials: D
authors.lastname: Travis
authors.forename: Nathan
authors.initials: N
authors.lastname: Lawrentschuk
mesh_terms: D005260:Female; D006417:Hematuria / Q000175:diagnosis* / Q000451:nursing; D006801:Humans; D008029:Lighting; D008297:Male; D015588:Observer Variation; D010108:Oxyhemoglobins; D010781:Photography; D012720:Severity of Illness Index
chemical_list: D010108:Oxyhemoglobins