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Related Concept Videos

Sample Size Calculation01:19

Sample Size Calculation

Knowledge of the sample size is the first requirement to conduct random sampling or an experiment. The sample size is the total number of units, observations, or groups (in some cases) used to get the data to estimate a population parameter. As the name suggests, the sample size is that of the sample drawn from the population and differs from the population size.
The sample size for the given experiment or sampling effort is fundamental to any study design. Sample size decides the number of...
Randomized Experiments01:13

Randomized Experiments

The randomization process involves assigning study participants randomly to experimental or control groups based on their probability of being equally assigned. Randomization is meant to eliminate selection bias and balance known and unknown confounding factors so that the control group is similar to the treatment group as much as possible. A computer program and a random number generator can be used to assign participants to groups in a way that minimizes bias.
Simple randomization
Simple...
Group Design02:01

Group Design

The most basic experimental design involves two groups: the experimental group and the control group. The two groups are designed to be the same except for one difference— experimental manipulation. The experimental group gets the experimental manipulation—that is, the treatment or variable being tested—and the control group does not. Since experimental manipulation is the only difference between the experimental and control groups, we can be sure that any differences between the two are due to...
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches01:23

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches

Biopharmaceutical studies constitute a vital field aiming to enhance drug delivery methods and refine therapeutic approaches, drawing upon diverse interdisciplinary knowledge. In research methodologies, the choice between controlled and non-controlled studies significantly influences the study's reliability and accuracy.
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...
Random Sampling Method01:09

Random Sampling Method

Sampling is a technique to select a portion (or subset) of the larger population and study that portion (the sample) to gain information about the population. Data are the result of sampling from a population. The sampling method ensures that samples are drawn without bias and accurately represent the population. Because measuring the entire population in a study is not practical, researchers use samples to represent the population of interest. Among the various sampling methods used by...
Systematic Sampling Method01:17

Systematic Sampling Method

Sampling is a technique to select a portion (or subset) of the larger population and study that portion (the sample) to gain information about the population. Data are the result of sampling from a population. The sampling method ensures that samples are drawn without bias and accurately represent the population. Because measuring the entire population in a study is not practical, researchers use samples to represent the population of interest.
Systematic sampling is one of the simplest methods...

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The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials
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How to calculate sample size in randomized controlled trial?

Baoliang Zhong1

  • 1Affiliated Mental Health Center, Tongji Medical College of Huazhong University of Science & Technology.

Journal of Thoracic Disease
|January 21, 2012
PubMed
Summary

Designing clinical trials requires careful consideration of sample size calculations. This review details statistical methods for estimating sample size requirements in randomized controlled trials.

Keywords:
Randomized Controlled TrialSample Size Calculation

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Area of Science:

  • Clinical Trials Methodology
  • Biostatistics
  • Research Design

Background:

  • Effective clinical trial design necessitates attention to efficiency, ethical considerations, cost-effectiveness, research duration, and sample size.
  • Accurate sample size estimation is crucial for the validity and feasibility of clinical trials.

Purpose of the Study:

  • To review the statistical issues involved in estimating sample size requirements for clinical trials.
  • To elaborate on the theory, methods, and steps for sample size calculation specifically within randomized controlled trials.

Main Methods:

  • Literature review focusing on statistical principles for sample size determination.
  • Explanation of theoretical underpinnings and practical methodologies for sample size calculation.

Main Results:

  • Highlights key statistical considerations for sample size estimation.
  • Provides a detailed overview of sample size calculation methods applicable to randomized controlled trials.

Conclusions:

  • Emphasizes the critical role of sample size calculations in clinical trial design.
  • Recommends that researchers prioritize study design selection before choosing a sample size calculation method.