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1. The primary difference in the focus of inquiry between clinical medicine and epidemiology involves the emphasis on the individual patient versus the population at large. Clinical medicine focuses on individual patients and may not be able to differentiate variability between patients, whereas epidemiology focuses on large groups of people or populations and what happens to whole groups.


2. The first “clinical drug trial’’ was performed by James Lind from 1747 through 1753. Lind performed a study on sailors aboard a ship at sea. He tested 6 treatments or interventions for scurvy by using 6 pairs of sailors (thus, 6 different treatment groups). Two sailors received citrus fruit and showed the greatest improvement.


3. In the host–agent–environment model, the host is the recipient of the disease. Host factors, also referred to as intrinsic factors, refer to various demographic as well as behavioral aspects of the host, human beings. The agent of disease, also called an etiological factor, can consist of a variety of things that are related to or cause specific disease states. The environment, or extrinsic factors, consists of the physical and social setting in which the host and agent interact, possibly leading to disease.


4. Definitions


  • a. Onset of a disease outbreak is represented by the first case exhibiting the signs and symptoms of that disease.
  • b. Etiology refers to the causative agent or risk factor that produces disease.
  • c. A vehicle is an inanimate object that may aid in the transmission, or spread, of a causative agent of disease.
  • d. Avector is an animate or living thing that may aid in the transmission, or spread, of a causative agent of disease.
  • e. Portals of entry or exit are the ways in which the causative agent enters and leaves the host.
  • f. A reservoir is a place where the causative agent may reside or spend part of its life cycle.
  • g. Mode of transmission refers to the ways in which a causative agent or risk factor may spread throughout a population.
  • h. An epidemic, also called an outbreak, is a sudden, dramatic increase in the number of people with a specific disease or problem. It is usually defined in terms of a specific population in an area over a period of time.
  • i. An incubation period is the interval of time between exposure to, or contact with, the causative agent or risk factor and the onset of the symptoms or condition.
  • j. Epidemiology is the study of disease occurrence in a human population. It also considers the distribution and determinants of disease. It may also be considered the method of public health.
  • k. Pharmacoepidemiology is the study of the nature and extent of drug-taking behaviors and drug use problems. It measures the source, diffusion, use, and effects of drugs in populations, with a focus on pharmaceutical care outcomes and the identification of potential or realized drug use problems.



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