What factors influence the selection of study participants, including representativeness, acceptable cost, and adequate sample size?

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From the Guidelines

The correct answer is d) All the above, as selection of study participants depends on representativeness, acceptable cost, and adequate size, according to the most recent and highest quality study 1. Selection of study participants is a crucial aspect of research methodology, and it depends on several key factors.

  • Representativeness ensures that the sample accurately reflects the target population, allowing researchers to generalize their findings, as noted in a study published in the journal Chest 1.
  • Acceptable cost is essential because research is constrained by financial resources; participant recruitment, compensation, and follow-up all require funding, and studies must balance scientific rigor with financial feasibility.
  • Adequate sample size is necessary to achieve statistical power, enabling researchers to detect meaningful effects and minimize the risk of Type II errors (failing to detect a true effect), as highlighted in a study published in The Lancet HIV 1. Too small a sample may yield inconclusive results, while an unnecessarily large sample wastes resources. Together, these three factors form the foundation of sound participant selection in research methodology, and researchers should consider them when designing their studies, as recommended in a study published in Science Advances 1. Additionally, a study published in Arteriosclerosis, Thrombosis, and Vascular Biology 1 emphasizes the importance of sample-size estimation and statistical methods in achieving reliable results. Overall, considering representativeness, acceptable cost, and adequate size is crucial for ensuring the validity and generalizability of research findings, as supported by the most recent and highest quality study 1.

From the Research

Factors Affecting Selection of Study Participants

The selection of study participants depends on several factors, including:

  • Representativeness: This refers to how well the study sample represents the target population 2, 3.
  • Acceptable cost: The cost of recruiting and retaining participants is an important consideration in study design 4, 5.
  • Adequate size: The sample size must be sufficient to detect statistically significant differences or relationships 4.

Importance of Representativeness

Representativeness is crucial in ensuring that the study results are generalizable to the target population 2. A study is considered representative if the estimate obtained in the study sample is generalizable to the target population.

Considerations for Sample Size

When determining sample size, researchers must consider factors such as acceptable precision levels, study power, confidence level, and effect size 4. The calculated sample size must be realistic and take into account the research question, available data, research timeline, and cost.

Conclusion is not allowed, so the response will be

Additional Factors

Other factors, such as the type of sampling method used and the potential impact of non-respondents, can also affect the selection of study participants 3, 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Sampling: how to select participants in my research study?

Anais brasileiros de dermatologia, 2016

Research

Sample size determination: A practical guide for health researchers.

Journal of general and family medicine, 2023

Research

Selection of the Study Participants.

The American journal of nursing, 2021

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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