Random Error Vs Bias

Question 1

What is Random Error?

Answer 1

A chance difference between the observed and the true values of something
- random error evens out if the sample is large enough
- random error also applies to clinical trials —> rates of natural healing are assumed
- unavoidable, no direction, cannot be replicated

Question 2

What is Bias?

Answer 2

A systemic error that distorts results in one direction and is sometimes very large (ex. Failure to publish small, negative RCT)
- can cause an ineffective intervention to appear to be effective