Your doctor says everything looks fine, but you still feel terrible. The problem might not be your health but how labs define “normal.” Understanding the difference between normal and optimal could ...

Using a blood pressure chart by age can help you interpret your results to see how they compare to the normal ranges across groups and within your own age cohort. Monitoring your blood pressure (BP) ...

Urine tests measure specific substances in your urine, such as electrolytes, proteins, and bacteria. These tests can reveal a lot about your health, particularly when gradual changes or big jumps ...

Men with a PSA level above the median for their age group are at higher risk for prostate cancer. The concept of what is "normal" enters into nearly every aspect of clinical decision making. For ...