Introduction
What do you believe?
Do you believe that cell phones cause brain cancer? Do you believe that acupuncture works? Do you believe that taking low-dose aspirin prevents heart attacks? Do you believe that the flu vaccine is safe? Do you believe that HIV causes AIDS? Or that high levels of cholesterol are a cause of heart attacks? Or that megadoses of vitamins are beneficial? Some people believe these things, but others do not. Who is correct? How should we decide?
Why do you believe what you believe?
Is it because other people believe it? Or because 'knowledgeable' people said it was true? Or because you read it somewhere? Or because people have always believed it? According to The Foundation for Critical Thinking, much of our thinking is unstructured. It is based on our past experiences, by what we have been told by people we love, people we respect, people in positions of authority, people with advanced degrees… people who are incorrect, misinformed, illogical, misguided, or mistaken. Much of what we believe, we just accept, despite the fact that it may be incorrect. It may be based on opinion, limited experience, anecdotal observation or downright bias, prejudice, or distortion. It is easier to believe, than to think. (Link to The Foundation for Critical Thinking)
Your First Assignment
There is controversy among the general public regarding the safety and efficacy of influenza vaccines. Watch the following short video on YouTube.com and consider both the evidence and the conclusions.
Video - Dystonia after receiving a seasonal flu shot·
After reflecting on the conclusions and evidence presented in the video, compose your thoughts regarding the conclusions that are implied. Here are some points that might be considered to guide your discussion:
- What was your initial reaction to the video? What reaction might you expect from the general public?
- What conclusions did the video suggest regarding the safety and efficacy of vaccines?
- What evidence was presented to support the conclusions?
- What (if any) vested interests were involved?
- Given a report of an unusual health problem like this, how might one methodically investigate whether there is an association, e.g., between getting a flu shot and developing dystonia?
- What are the criteria by which one determines whether a given factor is a "cause" of a particular outcome?
Critical Thinking
An alternative to just believing something is to think about it in a structured way, by which I mean:
- Identifying relevant questions
- Thinking in an open-minded way, i.e., considering alternative conclusions or explanations
- Gathering information carefully
- Evaluating the data objectively, methodically, and logically
- Questioning assumptions
- Making comparisons to test hypotheses
- Applying standard criteria and concepts
- Interpreting findings appropriately
- Communicating results clearly, honestly, and completely
- Considering alternative solutions and points of view
Epidemiology is a science that provides a way to establish (or refute) associations, by which I mean identifying factors that are associated with specific health outcomes (e.g., is heavy smoking associated with an increased risk of lung cancer?). I think of epidemiology as a discipline that provides a simple, logical methodology for thinking about associations in a structured way. However, epidemiologic thinking is relatively new and evolved slowly over the past few centuries. This module will provide a short historical perspective on how thinking about the determinants of health and disease has evolved over time.
Learning Objectives
After completing this module, the student will be able to:
- Explain the evolution of concepts about the cause and prevention of disease and the importance of studying the factors associated with outcomes in a systematic way in human populations.
- Discuss some of the major historical figures and events that played a role in the evolution of public health and epidemiology.
- Define epidemiology and explain its goals.
