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Apps in this category may contain frequent and intense offensive language; Frequent and intense cartoon, fantasy or realistic violence: frequent and intense adult, scary and sexually suggestive subjects: as well as sexual content, nudity, tobacco, alcohol and drugs, may not be suitable for children under 17 years of age.

n4Studies Screenshots

iPhone

About n4Studies

Ease to calculate the sample size with n4Studies.

n4Studies makes it easy to calculate the sample size and the power of a study. It comes with ABSOLUTELY NO WARRANTY. However, It can help to learn and find the ways to calculate the sample size and power of the study in minutes.

Key features:
• Calculate the sample size for estimating an infinite population mean, finite population mean, infinite population proportion and finite population proportion
• Calculate the sample size for comparing two population means and two population proportions
• Calculate the sample size for the Case-Control for study, Matched Case-Control study, Cohort study, Randomized Controlled Trial, Non-inferiority trial and Equivalence trial
• Calculate the power of a study for comparing two population means and two population proportions
• Calculate the power of a study for the Case-Control for study, Matched Case-Control study, Cohort study, Randomized Controlled Trial, Non-inferiority trial and Equivalence trial
• Calculate the power of a study for the Case-Control for study, Matched Case-Control study, Cohort study, Randomized Controlled Trial, Non-inferiority trial and Equivalence trial
• You can send a result via Email to your colleague

What's New in the Latest Version 2.3

Last updated on Feb 20, 2024

Old Versions

Fix some issues

Version History

2.3

Feb 20, 2024

Fix some issues

2.2

Aug 3, 2023

Version 2.2 - Add the probability calculations from odds ratio and risk ratio

2.1

Jun 29, 2023

Version 2.1 - Fix about image attachments
Version 2.0 - Change all user interfaces

2.0

Jun 27, 2023

• Added a sample size for comparing more than two independent groups (three or four groups)

1.4.1

Oct 29, 2014

This app has been updated by Apple to display the Apple Watch app icon.

• Changed the formulas for calculating the sample size of non-inferiority and superiority trial (two sample design)
• Added the sample size and power calculations for non-inferiority and superiority in one-sample design

1.3.0

Aug 26, 2014

• Sample size formula(s) is/are shown on each sample size calculation and help screens
• Added the text fields for design effect in sample size calculations for estimations.
• Added the calculations for a test performance (sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, and etc.)

1.2.0

May 29, 2014

fixed bugs

1.1.0

Jan 24, 2014

• Add the results from a continuity correction
• Add the calculation for Chi-squared test, OR. and RR. from 2 by 2 table

1.0.0

Aug 7, 2013

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