Final answer:
Etiology is another word for cause. Epidemiologists study diseases to determine the cause, known as the etiologic agent or causative agent. Diagnosis can be complicated due to nonspecific signs and symptoms.
Step-by-step explanation:
Etiology is another word for cause. When studying diseases, epidemiologists aim to determine the cause of the disease, known as the etiologic agent or causative agent. They use controlled experiments to eliminate other possible causes and connect the disease to a specific pathogen. This can be challenging as signs and symptoms of disease are often nonspecific, making diagnosis complicated.