Sample Size Calculation Explained

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Sample Size Calculation Explained

Sample Size Calculation is a crucial part of study design. The sample size must be chosen correctly to allow a study to arrive a valid conclusions for the given scientific question. A study with a sample size that is too small may produce inconclusive results, while a study with a sample size that is too large will waste scarce resources.

The sample size of a statistical sample is the number of observations that constitute it. It is typically denoted n, a positive integer (natural number). Typically, all else being equal, a larger sample size leads to increased precision in estimates of various properties of the population, though the results will become less accurate if there is a systematic error in the experiment. This can be seen in such statistical rules as the law of large numbers and the central limit theorem. Repeated measurements and replication of independent samples are often required in measurement and experiments to reach a desired precision.

Sample Size Calculation Software

nQuery Advisor is the world’s leading sample size calculation software application. It is used by 1,000’s of researchers, statisticians, clinicians and data analysts at all leading global pharmaceutical and biotechnology companies, at renowned research institutes and universities and importantly, it is also the sample size calcualtion software of choice at regulatory agencies such as FDA.

nQuery Advisor allows you to:

Quickly and easily calculate your sample size and power
Easily generate your sample size calculation justification statement
Compare different sample size calculation options with easily customizable plots
Perform sample size and power calculations for a wide variety of statistical analyses
Work with a sample size calculation package that is used by leading regulatory agencies

 

Watch a short video on how easy it is to perform sample size calculations using nQuery Advisor

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