nQuery is a clinical trial design platform used for the design and monitoring of adaptive, group sequential, and fixed sample size trials. It is most commonly used by biostatisticians to calculate

sample size Sample size determination is the act of choosing the number of observations or Replication (statistics), replicates to include in a statistical sample. The sample size is an important feature of any empirical study in which the goal is to make stat ...

and

statistical power In statistics, the power of a binary hypothesis test is the probability that the test correctly rejects the null hypothesis (H_0) when a specific alternative hypothesis (H_1) is true. It is commonly denoted by 1-\beta, and represents the chances ...

for adaptive clinical trial design. nQuery is proprietary software developed and distributed by

Statsols Statsols (formerly known as Statistical Solutions) is the producer and distributor of the proprietary nQuery sample size software. History In 1984, Statsols (Originally known as Statistical Solutions) was a distributor for the statistical softwa ...

. The software includes calculations for over 1,000 sample sizes and power scenarios.

History

Janet Dixon Elashoff, creator of nQuery, is a retired American statistician and daughter of the mathematician and statistician Wilfrid Joseph Dixon, creator of BMDP. Elashoff is also the retired Director of the Division of Biostatistics,

Cedars-Sinai Medical Center Cedars-Sinai Medical Center is a nonprofit, tertiary, 886-bed teaching hospital and multi-specialty academic health science center located in Los Angeles, California. Part of the Cedars-Sinai Health System, the hospital employs a staff of over 2 ...

. While at

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California St ...

and Cedars-Sinai during the 1990s, she wrote the program nQuery Sample Size Software (then named nQuery Advisor). This software quickly became widely used to estimate the sample size requirements for pharmaceutical trials. She joined the company Statistical Solutions LLC in order to commercialize it. In June 2020, nQuery was acquired by Insightful Science.

Uses

nQuery is used for adaptive clinical trial design. Trials with an adaptive design have been reported to be more efficient, informative, and ethical than trials with a traditional fixed design because they conserve resources such as time and money and often require fewer participants. nQuery allows researchers to apply both

frequentist Frequentist inference is a type of statistical inference based in frequentist probability, which treats “probability” in equivalent terms to “frequency” and draws conclusions from sample-data by means of emphasizing the frequency or pr ...

and

Bayesian Thomas Bayes (/beɪz/; c. 1701 – 1761) was an English statistician, philosopher, and Presbyterian minister. Bayesian () refers either to a range of concepts and approaches that relate to statistical methods based on Bayes' theorem, or a followe ...

statistics to calculate the appropriate sample size for their study.

References

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External links

Official Statsols Page for nQuery
Sampling (statistics) Science software Statistical software