--- title: Hypothesis Testing Example - GSK COPD Research - Calculate sample size description: Hypothesis Testing Example - Learn to calculate sample size and use a power analysis calculator for clinical trials. This example focuses on GSK COPD Research. image: https://www.statsols.com/hubfs/Master_Images/___HeroBannerImages/nQuery%20Sample%20Size%20Software%20Image.png --- Explore the Scientific R&D Platform ![Top Bar background texture](https://flow-cytometry.net/wp-content/uploads/2024/07/nav-bg.png) ![](https://flow-cytometry.net/wp-content/uploads/2024/07/Luma-TM.png) Scientific intelligence platform for AI-powered data management and workflow automation [Explore Luma   ](https://www.dotmatics.com/luma-data-management-platform) [![Prism logo](https://flow-cytometry.net/wp-content/uploads/2024/07/Prism-Logo-White-2.png) Statistical analysis and graphing software for scientists ](https://www.graphpad.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![Geneious logo](https://flow-cytometry.net/wp-content/uploads/2024/07/Geneious-Logo-White-2.png) Bioinformatics, cloning, and antibody discovery software ](https://www.geneious.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![SnapGene logo](https://cdn.labarchives.com/assets/16.23.0/assets/images/dotmatics/lab-archives/top-bar/PreNav-Logo-SnapGene.svg) Plan, visualize, & document core molecular biology procedures ](https://www.snapgene.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![Protein Metrics logo](https://cdn.labarchives.com/assets/16.23.0/assets/images/dotmatics/lab-archives/top-bar/PreNav-Logo-Protein-Metrics.svg) Proteomics software for analysis of mass spec data ](https://proteinmetrics.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![LabArchives logo](https://flow-cytometry.net/wp-content/uploads/2024/07/LabArchives-Logo-White-2.png) Electronic Lab Notebook to organize, search and share data ](https://www.labarchives.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![OMIQ logo](https://cdn.labarchives.com/assets/16.23.0/assets/images/dotmatics/lab-archives/top-bar/PreNav-Logo-OMIQ.svg) Modern cytometry analysis platform ](https://www.omiq.ai/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![FCS Express logo](https://cdn.labarchives.com/assets/16.23.0/assets/images/dotmatics/lab-archives/top-bar/PreNav-Logo-FCS-Express.svg) Analysis, statistics, graphing and reporting of flow cytometry data ](https://denovosoftware.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![Easy Panel logo](https://flow-cytometry.net/wp-content/uploads/2024/07/EasyPanel-Logo-White-2.png) Intelligent panel design & inventory management for flow cytometry ](https://flow-cytometry.net/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![nQuery logo](https://cdn.labarchives.com/assets/16.23.0/assets/images/dotmatics/lab-archives/top-bar/PreNav-Logo-nQuery.svg) Software to optimize designs of clinical trials ](https://www.statsols.com/) [![M-Star logo](https://flow-cytometry.net/wp-content/uploads/2024/07/M-Star-Logo-White-2.png) Computational fluid dynamics (CFD) software for engineers and researchers ](https://www.mstarcfd.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [![SoftGenetics logo](https://flow-cytometry.net/wp-content/uploads/2024/07/SoftGenetics-Logo-White-2.png) Genetic analysis software for research, forensics & healthcare applications ](https://softgenetics.com/?utm_medium=referral&utm_source=nquery&utm_campaign=dotmatics-top-bar) [Explore the Scientific Software   ](https://www.dotmatics.com/portfolio) [![nQuery Logo](https://www.statsols.com/hubfs/nQuery%20Logo.svg "nQuery Logo")](https://www.statsols.com/) [![Pricing](https://no-cache.hubspot.com/cta/default/488764/23ddd076-07af-4f0a-9388-5a58a5369002.png)](https://cta-redirect.hubspot.com/cta/redirect/488764/23ddd076-07af-4f0a-9388-5a58a5369002) [![Free Trial](https://no-cache.hubspot.com/cta/default/488764/93ddde0f-93b2-4893-a3db-0523d2334739.png)](https://cta-redirect.hubspot.com/cta/redirect/488764/93ddde0f-93b2-4893-a3db-0523d2334739) # Sample Size Determination Example ## AREA: Means | Respiratory ![nQuery In Use Background Web Opacity 35](https://www.statsols.com/hs-fs/hubfs/Master_Images/___HeroBannerImages/nQuery%20In%20Use%20Background%20Web%20%20Opacity%2035.png?width=1920&name=nQuery%20In%20Use%20Background%20Web%20%20Opacity%2035.png "nQuery In Use Background Web Opacity 35") #### GSK Chronic obstructive pulmonary disease (COPD) Research #### Title: Once daily inhaled fluticasone furoate and vilanterol versus vilanterol only for prevention of exacerbations of COPD: Two replicate double blind, parallel-group, randomised controlled trials **Objective: **Whether the combination of a once-daily inhaled corticosteroid with a once-daily longacting β2 agonist is more protective than a once-daily longacting β2 agonist alone against exacerbations of chronic obstructive pulmonary disease (COPD) is unknown. We hypothesised that fluticasone furoate and vilanterol would prevent more exacerbations than would vilanterol alone. **Year:** 2013 **Source:** Lancet Respiratory Medicine **Link: [https://www.sciencedirect.com/science/article/abs/pii/S2213260013700407](https://www.sciencedirect.com/science/article/abs/pii/S2213260013700407)** **Clinical Area: **Respiratory | **Sample Size Section in Paper/Protocol:** | | --- | | “On the basis of previous studies of fluticasone propionate–salmeterol combinations we assumed a yearly exacerbation rate with vilanterol of 1·4 and a dispersion parameter of 0·7. Thus, we calculated that a sample size of 390 assessable patients per group in each study would provide each study with 90% power to detect a 25% reduction in exacerbations in the fluticasone furoate and vilanterol groups versus the vilanterol only group at a two-sided 5% significance level” | ** Summary of Necessary Parameter Estimates for Sample Size Calculation:** |  Parameter | Value | | --- | --- | |  Significance Level (2-Sided) | 0.05 | |  Control Rate | 1.4 | |  Rate Ratio | 0.75 | |  Dispersion Parameter | 0.7 | |  Exposure Time (Years) | 1 | | Power | 90% | #### **Email me this example in PDF format** **Step 1: **Select the **Two Group Test Comparing Incidence Rates using the Negative Binomial Model **from the Select Test Design & Goal window. This can be done **using the radio buttons** or alternatively, you can** use the search bar** at the end of the Select Test Design & Goal window. ![Sample Size Calculator Example- nQuery- Example 13- Img 01- Two Group Test Comparing Incidence Rates using the Negative Binomial Model](https://www.statsols.com/hs-fs/hubfs/Master_Images/___PageImages/Worked%20Examples/nQuery%20Example%20Images/Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2001-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png?width=579&name=Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2001-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png)   **Step 2: **Enter the parameter values for sample size calculation taken from the study description. ![Sample Size Calculator Example- nQuery- Example 13- Img 02- Two Group Test Comparing Incidence Rates using the Negative Binomial Model](https://www.statsols.com/hs-fs/hubfs/Master_Images/___PageImages/Worked%20Examples/nQuery%20Example%20Images/Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2002-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png?width=477&name=Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2002-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png) **Step 3: **Select **Run** to calculate for sample size. | The analysis calculates a sample size of 390 per group with 90.05% power, as per the study. | | --- | ** ![Sample Size Calculator Example- nQuery- Example 13- Img 03- Two Group Test Comparing Incidence Rates using the Negative Binomial Model](https://www.statsols.com/hs-fs/hubfs/Master_Images/___PageImages/Worked%20Examples/nQuery%20Example%20Images/Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2003-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png?width=434&name=Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2003-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png)** **Step 4: **Once the calculation is completed, nQuery Advanced provides an output statement summarizing the results. It States: | **Output Statement:** | | --- | | The comparison of two event (incidence) rates using a Negative Binomial model with a group 1 sample size of 390 and a group 2 sample size of 390 achieves 90.05% power at the 0.05 significance level when the mean incidence rate in group 1 is 1.4 and the rate ratio is 0.75. This assumes the mean exposure time was 1 and the two groups have a common dispersion parameter of 0.7. This assumes the variance under the null hypothesis was calculated using the (Control Group Rate/True Rates/Maximum Likelihood) method |   ![Sample Size Calculator Example- nQuery- Example 13- Img 04- Two Group Test Comparing Incidence Rates using the Negative Binomial Model](https://www.statsols.com/hs-fs/hubfs/Master_Images/___PageImages/Worked%20Examples/nQuery%20Example%20Images/Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2004-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png?width=760&name=Sample%20Size%20Calculator%20Example-%20nQuery-%20Example%2013-%20Img%2004-%20Two%20Group%20Test%20Comparing%20Incidence%20Rates%20using%20the%20Negative%20Binomial%20Model.png) #### **Email me this example in PDF format** ### Free 14 Day Trial ![Demo Icon white](https://www.statsols.com/hs-fs/hubfs/Demo%20Icon%20white.png?width=330&name=Demo%20Icon%20white.png) **No download required**   [Try Now](https://www.statsols.com/nquery-demo) ##### **LOCATION** GraphPad Software DBA Statistical Solutions, 225 Franklin St FL 26 Boston, MA, 02110-2853, United States Copyright © Statsols. 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