Underpowered studies can result from several factors:
1. Small Sample Size: One of the most common reasons for a study being underpowered is a sample size that is too small. Smaller samples provide less reliable estimates and greater variability. 2. Low Effect Size: If the effect size (the magnitude of the association or difference) is smaller than anticipated, even studies with a seemingly adequate sample size can be underpowered. 3. High Variability: High variability within the data can obscure true effects, making it harder to detect significant associations. 4. Poor Study Design: Inadequate planning, including flaws in randomization, blinding, and control of confounders, can lead to underpowered studies.
