HLTB15H3 Lecture Notes - Lecture 9: Recall Bias, Informed Consent, Comparator
Document Summary
Lecture 9 experimental methods & non-experimental methods. Rely on scientific methods to test hypothesis (a -> b) Examine the relationship between an independent variable (cause) and dependent variable (effect) Advantages: ability to test hypothesis, reduce bias, limit confounding. Effect size: statistical estimate of the magnitude of a change. Identification of causal factors: introduction/exclusion of factors to identify which factors most likely caused the observed outcome. Use of controls: experiments involve the manipulation of variables to help identify factors that are significant (in terms of their effects) Empirical observation and precise measurement: we do these in regards to the changes that occur following the intervention. Confounding an important potential source of bias. When something other than the exposure of interest is responsible for the observed relationship. A threat to the (internal) validity of a research study. Example when assessing risk of disease, factors like age and ses can impact risk and therefore should be controlled.
