Why do you report THC concentrations as a ratio of THC/creatinine?
THC concentrations are calculated as a ratio of THC/creatinine to account for variations in hydration states. This is important for THC which can be present for up to 30 days and differences in hydration states can result in misleading results when determining “reuse” or “washout”. By calculating the ratio, results are normalized and ratios can be used directly to determine if the patient has reused.
