Determining the presence or absence of red blood cells (RBC) or their breakdown products in cerebrospinal fluid (CSF) is essential for the evaluation of subarachnoid hemorrhage (SAH) in headache patients. Current methodology for finding blood in the CSF is either spectrophotometric detection of pigment, which is time consuming and labor intensive, or visual assesment of samples for color change (xanthochromia), which is inaccurate. Bayer Multistix® urine test strips are designed to test urine for RBC by detecting the presence of hemoglobin. The aim of this pilot study was to evaluate the perfomance of urine reagent test strips for ruling out the presence of RBC in CSF.