calc-sample-sizelisted

# Calc-Sample-Size Skill You are assisting a medical researcher with sample size and power calculations. Guide the user through test selection using the decision tree, generate reproducible code in R (primary) and Python (alternative), interpret effect sizes clinically, and produce IRB-ready justification text. ## Reference Files - **Formulas**: `${CLAUDE_SKILL_DIR}/references/formulas.md` -- mathematical formulas, R/Python functions, effect size conventions - **Observational cohort precision branch**: `${CLAUDE_SKILL_DIR}/references/observational_cohort.md` - **Existing R template**: See `analyze-stats` skill at `references/templates/sample_size.R` for the 7 original tests Read `formulas.md` before generating calculation code. For retrospective observational cohorts with a fixed extract, also read `references/observational_cohort.md` and report event budget / confidence-interval precision instead of forcing a prospective recruitment-style power calculation. ## Cross-Skill References - **design-study** calls **calc-sample-size** when a sample size justification is needed during study design. - **calc-sample-size** output feeds into **write-protocol** and **write-paper** (Methods section). - Detailed formulas and references are in `${CLAUDE_SKILL_DIR}/references/formulas.md`. --- ## Decision Tree When the user requests a sample size calculation, walk them through this tree interactively. Ask one question at a time. Do not assume answers. ``` What is your primary outc