Sample Size in 4 Easy Steps

1. Formulate the study design, outcome, analysis.

Use the nQuery Advisor Study Goal and Design box to select the right table.

2. Use nQuery Advisor’s spreadsheet-style tables to specify analysis parameters and expected differences.

3. Enter sample size to have nQuery Advisor compute power (or interval width) or specify power to compute sample size.

Additional columns with alternative values for effect size can be entered for sensitivity analysis.

4. Quickly evaluate a range of scenarios with nQuery Advisor’s tables and plots. Choose the sample size which best satisfies your goals and plausible parameter values. nQuery Advisor can then write up the sample size decision. This unique feature makes it easy to report the sample size decision in the correct language and format.