What Do Blood Tests Show? (NIH)
"For many blood substances, the normal range is the range of levels seen in 95 percent of healthy people in a certain group. For many tests, normal ranges vary depending on your age, gender, race, and other factors."
Analysis of body fluids for forensic purposes: From laboratory testing to non-destructive rapid confirmatory identification at a crime scene (Forensic Science International)
"Body fluid traces recovered at crime scenes are among the most important types of evidence to forensic investigators. They contain valuable DNA evidence which can identify a suspect or victim as well as exonerate an innocent individual."