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  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4]

  3. PS Power and Sample Size - Wikipedia

    en.wikipedia.org/wiki/PS_Power_and_Sample_Size

    The program provides methods that are appropriate for matched and independent t-tests, [2] survival analysis, [5] matched [6] and unmatched [7] [8] studies of dichotomous events, the Mantel-Haenszel test, [9] and linear regression. [3] The program can generate graphs of the relationships between power, sample size and the detectable alternative ...

  4. Stepped-wedge trial - Wikipedia

    en.wikipedia.org/wiki/Stepped-wedge_trial

    Fourth, a design effect (used to inflate the sample size of an individually randomized trial to that required in a cluster trial) has been established, [11] which has shown that the stepped wedge CRT could reduce the number of patients required in the trial compared to other designs. [11] [15]

  5. nQuery Sample Size Software - Wikipedia

    en.wikipedia.org/wiki/NQuery_Sample_Size_Software

    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 and statistical power for adaptive clinical trial design. nQuery is proprietary software developed and distributed by Statsols. The ...

  6. Completely randomized design - Wikipedia

    en.wikipedia.org/wiki/Completely_randomized_design

    (where ! denotes factorial) possible run sequences (or ways to order the experimental trials). Because of the replication , the number of unique orderings is 90 (since 90 = 6!/(2!*2!*2!)). An example of an unrandomized design would be to always run 2 replications for the first level, then 2 for the second level, and finally 2 for the third level.

  7. Design effect - Wikipedia

    en.wikipedia.org/wiki/Design_effect

    If the sample size is 1,000, then the effective sample size will be 500. It means that the variance of the weighted mean based on 1,000 samples will be the same as that of a simple mean based on 500 samples obtained using a simple random sample.

  8. OpenEpi - Wikipedia

    en.wikipedia.org/wiki/OpenEpi

    Test for trend with count data; Independent t-test and one-way ANOVA; Diagnostic and screening test analyses with receiver operating characteristic (ROC) curves; Sample size for proportions, cross-sectional surveys, unmatched case-control, cohort, randomized controlled trials, and comparison of two means

  9. Average treatment effect - Wikipedia

    en.wikipedia.org/wiki/Average_treatment_effect

    In a randomized trial (i.e., an experimental study), the average treatment effect can be estimated from a sample using a comparison in mean outcomes for treated and untreated units. However, the ATE is generally understood as a causal parameter (i.e., an estimate or property of a population ) that a researcher desires to know, defined without ...