# Sample size estimation: how many individuals should be studied?

@article{Eng2003SampleSE, title={Sample size estimation: how many individuals should be studied?}, author={John Eng}, journal={Radiology}, year={2003}, volume={227 2}, pages={ 309-13 } }

The number of individuals to include in a research study, the sample size of the study, is an important consideration in the design of many clinical studies. This article reviews the basic factors that determine an appropriate sample size and provides methods for its calculation in some simple, yet common, cases. Sample size is closely tied to statistical power, which is the ability of a study to enable detection of a statistically significant difference when there truly is one. A trade-off…

## 708 Citations

### Sample size calculation in epidemiological studies

- Mathematics
- 2006

Summary Sample-size determination is often an important step in planning an epidemiological study. There are several approaches to determining sample size. It depends on the type of the study.…

### Sample Size Estimation in Clinical Research: From Randomized Controlled Trials to Observational Studies.

- BusinessChest
- 2020

### Sample Size Estimation: A Glimpse beyond Simple

- Mathematics
- 2004

The method of simulation is presented as a general technique with which sample size may be calculated for complex study designs and applications of simulation for determining sample size requirements in studies involving correlated data and comparisons of receiver operating characteristic curves are discussed.

### Some Notes on The Sample Size determination

- Educationالمجلة العملیة التجارة والتمویل
- 2018

Sample size determination is often important step in planning a statistical study. Studies that are too small sizes of samples may lead to inaccurate results but studies that are too large sizes of…

### Theory and practice Sample size calculation in epidemiological studies

- Mathematics
- 2007

Sample-size determination is often an important step in planning an epidemiological study. There are several approaches to determining sample size. It depends on the type of the study. Descriptive,…

### Sample size estimation: a glimpse beyond simple formulas.

- MathematicsRadiology
- 2004

The method of simulation is presented as a general technique with which sample size may be calculated for complex study designs and applications of simulation for determining sample size requirements in studies involving correlated data and comparisons of receiver operating characteristic curves are discussed.

### Sample Size Calculation In Medical Research

- Medicine2019 13th International Conference on Mathematics, Actuarial Science, Computer Science and Statistics (MACS)
- 2019

This review covers most frequently encountered study designs in medical research and provides statistical formulas for the sample size calculation of the research studies with varying objectives such as estimation of population proportion(s) and hypothesis testing, estimates of population mean, estimation of diagnostic accuracy, and estimation of association and reliability.

### Sample Size Determination in Descriptive Study in Public Health

- 2013

Descriptive study is frequently used in public health research. Choosing an appropriate statistical method is to determine sample size yielded appropriate and sufficient number of samples into the…

### Sample size estimation and statistical power analyses

- Economics
- 2010

A step-by-step guide of the process for determining sample size and statistical power is presented, which builds on statistical concepts presented in earlier articles in Optometry Today.

### Sample size in clinical research, the number we need -

- Medicine
- 2012

The objective of the current narrative review is to illustrate the methodology of sample size calculation for comparative and descriptive research, which will be most useful for the beginners.

## References

SHOWING 1-10 OF 18 REFERENCES

### Statistical power, sample size, and their reporting in randomized controlled trials.

- MedicineJAMA
- 1994

The pattern over time in the level of statistical power and the reporting of sample size calculations in published randomized controlled trials (RCTs) with negative results is described and few trials discussed whether the observed differences were clinically important.

### Designing Clinical Research: An Epidemiologic Approach

- Psychology
- 1989

"Why this sample size?" "But those aren't parametric data." "That's not an appropriate control group!" So it goes when editors meet to decide which studies to publish and which not. There is lots of…

### Are all significant P values created equal? The analogy between diagnostic tests and clinical research.

- MedicineJAMA
- 1987

Knowing the P value and power, or the confidence interval, for the results of a research study is necessary but insufficient: the reader must estimate the prior probability that the research hypothesis is true.

### The importance of beta, the type II error and sample size in the design and interpretation of the randomized control trial. Survey of 71 "negative" trials.

- MedicineThe New England journal of medicine
- 1978

Concern for the probability of missing an important therapeutic improvement because of small sample sizes deserves more attention in the planning of clinical trials.

### Statistical methods for rates and proportions

- Computer Science
- 1973

An Introduction to Applied Probability: The Basic Theory of Maximum Likelihood Estimation and Answers to Selected Problems.

### Practical statistics for medical research

- Medicine
- 1990

Practical Statistics for Medical Research is a problem-based text for medical researchers, medical students, and others in the medical arena who need to use statistics but have no specialized mathematics background.

### Principles of biostatistics

- Mathematics
- 1992

1. INTRODUCTION Overview / Review Exercises / Bibliography 2. DATA PRESENTATION Types of Numerical Data / Tables / Graphs / Further Applications / Review Exercises / Bibliography 3. NUMERICAL SUMMARY…

### FUNDAMENTALS OF BIOSTATISTICS

- Mathematics
- 1969

reciprocal systems, co- and contra-variant components, orthogonal curvilinear systems. Matrix theory: Gauss-Jordan elimination, eigenvalues and eigenvectors, quadratic and canonical forms.…

### Statistical Practice The Abuse of Power: The Pervasive Fallacy of Power Calculations for Data Analysis

- Psychology
- 2001

### Repeated measures in clinical trials: analysis using mean summary statistics and its implications for design.

- MedicineStatistics in medicine
- 1994