Does it matter what time of day I collect my sample?

Yes, timing matters somewhat. OncuraKit recommends collecting a mid-stream urine sample during the middle part of the day — ideally 2–4 hours after your last urination. Avoid collecting the very first morning urine (overnight-concentrated urine can have higher contaminant levels) and very dilute late-afternoon urine (if you've been drinking excessive fluids). The Yenos HL normalization compensates for variation in urine concentration, so mild timing differences are acceptable. The most important factors are: not collecting during an active urinary tract infection, not collecting within 48 hours of a significant acute illness with fever, and following the mid-stream technique described in the collection instructions to minimize contamination from urethral flora.