Three Ways In -- Navigation Pathways
The module offers three entry pathways so you can reach the right calculator however you think about your study. All three converge on the same underlying calculators.
| Pathway | Starting point | Best for |
|---|---|---|
| I Know My Goal (Purpose-driven) -- recommended | Your research objective | You know why but not which test |
| I Know My Outcome (Outcome-driven) | Type of data you'll collect | You know what you'll measure |
| I Know My Test (Advanced) | A specific statistical test | You know exactly which calculator |
"I Know My Goal" -- Purpose-driven
Starts from your research objective. Pick a purpose, then choose the specific outcome.
| Purpose | What it covers |
|---|---|
| Compare Treatments or Groups | Comparing interventions, drugs, or group differences |
| Assess Risk Factors | Case-control or cohort studies (OR, RR) |
| Study Survival or Time-to-Event | Survival endpoints or hazard ratios |
| Evaluate a Diagnostic Test | Sensitivity, specificity, diagnostic accuracy |
| Estimate Prevalence or Conduct a Survey | Survey sample size or disease-frequency estimation |
| Measure Correlation Between Variables | Association strength between two measures |
| Develop or Validate a Measurement Scale | Psychometric studies for reliability/validity |
| Measure Observer Agreement | Inter-rater reliability, ICC, or Kappa |
| Show Drug Equivalence | Bioequivalence studies |
| Plan an Animal or Preclinical Study | Mead's resource equation or power analysis |
After choosing a purpose, specific outcomes are shown. For example, "Compare Treatments or Groups" offers: Laboratory Results, Quality of Life Scales, 6-Minute Walk Test, Tumor Size, Pain Scores, Mortality/Cardiovascular Events, Adverse Events, Ordinal/Graded Outcomes, Composite Endpoints. Choosing an outcome launches the wizard.
"I Know My Outcome" -- Outcome-driven
Starts from the type of data you will collect:
| Category | What it covers |
|---|---|
| Continuous Measurements | Lab results, scores, distances, sizes |
| Binary & Categorical Events | Yes/no outcomes, event rates, graded categories |
| Risk Measures | Odds ratios and relative risks |
| Time-to-Event / Survival | Survival analysis, hazard ratios |
| Diagnostic Accuracy & Prediction | Sensitivity, specificity, ROC curve |
| Correlation | Pearson or Spearman correlation |
| Survey & Prevalence | Population surveys, prevalence estimation |
| Agreement & Reliability | Inter-rater reliability |
Each outcome includes clinically meaningful defaults from the literature. Picking an outcome launches the wizard.
"I Know My Test" -- Advanced
Lists every calculator directly. Jump straight to the one you need.
Sample Size Calculators (A-priori):
| Calculator |
|---|
| Paired Means |
| Independent Means |
| Independent Proportions |
| Correlation Coefficient |
| Two Correlation Coefficients |
| Odds Ratio |
| Relative Risk |
| ROC Curve (AUC) |
| Survival / Time-to-Event |
| Prevalence / Population Survey |
| Mead's Method (Animal Studies) |
| Repeated Measures ANOVA |
Post-Hoc Power Calculators:
| Calculator |
|---|
| Two Proportions |
| Two Means |
| ANOVA (One-Way) |
| Chi-Square |
| Odds Ratio |
| Correlation |
| Paired Means |
| Relative Risk |
How the pathways relate
I Know My Goal --\
+--> Outcome-Based Wizard --> configured calculation
I Know My Outcome --/
I Know My Test -----> Individual calculator --> direct calculation
The Goal and Outcome pathways are guided -- they help arrive at the correct calculator and pre-fill the design. The Test pathway is direct -- fastest when you already know your design. The underlying statistics and Methods Section output are the same regardless of route.
If unsure which test your study needs, start with "I Know My Goal." If you know your data type, use "I Know My Outcome." If you know your test by name, use "I Know My Test."