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Trial Factors that Modify Sample Size
| FACTOR | DIRECTION OF CHANGE IN SIZE OF FACTOR* |
CHANGE IN SAMPLE SIZE |
|---|---|---|
|
| ||
| Type 1 error | decrease | larger |
|
| ||
| Power | increase | larger |
|
| ||
| Effect size | decrease | larger |
| discrete | close to 0.5 | larger |
| time-to-event | fewer events | larger |
Assumes that only one factor changes at a time.
