Sample size determination is one of the most common tasks required when planning a study. With our power analysis software, we want to make sure that when you're conducting a sample size determination, the process is intuitive, quick and easy.
In nQuery, the spreadsheet format means generating a sample size result is a quick and easy process. In a sample size table you will find on the left hand side a full list of the assumptions required for your sample size calculation. This means there is no requirement on you to research or look up what these assumptions would have been. In the spreadsheet format, generating a sample size result is simply a matter of entering your values into the spreadsheet which means there is no requirement for coding experience to quickly get your result. This means that you will get to the sample size you require in a quick and timely manner.
With nQuery if at any point you were unsure about an assumption required for a sample size determination, we work to ensure that you can understand what that assumption is and what some common values for that assumption would be. When you select a row in nQuery, automatically on the right hand side you will find a help card which will give a description of what that assumption is, a suggestion for what that value will often be set to and the full range of values which are acceptable for that. Values outside the acceptable entries would be rejected by nQuery. In addition, we provide a table help card which provides some guidance both on how to use the table and the references used to derive the table.
We also provide a comprehensive manual which will allow you to understand how each feature in nQuery works and also how each sample size table works individually and how it was derived. This can be easily found under the help menu in nQuery.
At nQuery, we highly value the advice of our clients and customers. If there's a feature that you believe is missing in nQuery or a sample size calculation that could be added in a future release, please let us know and we will be happy to provide that as soon as possible and also provide prototypes or other resources that may help you find the appropriate sample size for your study.