Diagnostic technique helps us to identify a disease. It have complex equipment that produce image such as X - rays or scans. When body fails to function properly, professionals typically order diagnostic procedures. In diagnostic technique many complex steps of biotechnology performes. Example: ELISA is a diagnostic test for HIV.

Once a cause in identified, therapeutic procedure performed to the disease therapeutic radiographers use radiation to treat cancer and tissue defects. Simply a therpeutic agents helps in the treatment of disease. Example: Antibiotics for bacterial infections.