Several factors can contribute to observer bias in epidemiological studies:
- Preconceptions and Expectations: The observer's prior beliefs, clinical experiences, or expectations about the study outcomes can bias their observations. - Lack of Blinding: When observers are aware of the participants' exposure or intervention status, their observations and measurements can be biased. - Inconsistent Measurement Techniques: Variability in how different observers or even the same observer at different times collect and record data can introduce bias.
