experiment-design

# Experiment Design Skill

## Purpose
Design methodologically rigorous experiments with appropriate controls and randomization.

## Key Design Elements

**1. Research Question**: Clear, testable hypothesis
**2. Study Design**: RCT, quasi-experimental, observational
**3. Sample Size**: Power analysis justified
**4. Randomization**: Method specified
**5. Blinding**: Who is blinded
**6. Controls**: Appropriate comparison groups
**7. Outcomes**: Primary and secondary clearly defined
**8. Analysis Plan**: Pre-specified statistical approach

## Common Designs

**Between-Subjects**: Different participants per condition
**Within-Subjects**: Same participants, repeated measures
**Factorial**: Multiple factors (2x2, 2x3)
**Crossover**: Participants receive all treatments
**Stepped-Wedge**: Phased rollout

## NIH Rigor Checklist

- [ ] Scientific premise established
- [ ] Rigorous design (appropriate controls)
- [ ] Biological variables considered (SABV)
- [ ] Authentication of key resources
- [ ] Transparent reporting planned

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**Version:** 1.0.0