Types of bias

To recap, so far, we’ve defined bias as “deviation from the truth” or the “likelihood that the way the study was conducted led to incorrect findings.” That’s great. But we need to get more specific for our actual assessment.  

For this course, we’ll use the six major types of bias as defined by Cochrane, a collaboration of individuals from around the world conducting systematic reviews:

1. Selection bias

2. Performance bias

3. Detection bias

4. Attrition bias

5. Reporting bias

6. Other biases

*This is another example of where there’s some disagreement. Depending on your academic field, you might see types of bias categorized or defined in different ways.