The Indian Journal of Pediatrics

, Volume 79, Issue 11, pp 1482–1488 | Cite as

Sample Size Estimation in Prevalence Studies

  • Ravindra AryaEmail author
  • Belavendra Antonisamy
  • Sushil Kumar
Special Article


Estimation of appropriate sample size for prevalence surveys presents many challenges, particularly when the condition is very rare or has a tendency for geographical clustering. Sample size estimate for prevalence studies is a function of expected prevalence and precision for a given level of confidence expressed by the z statistic. Choice of the appropriate values for these variables is sometimes not straight-forward. Certain other situations do not fulfil the assumptions made in the conventional equation and present a special challenge. These situations include, but are not limited to, smaller population size in relation to sample size, sampling technique or missing data. This paper discusses practical issues in sample size estimation for prevalence studies with an objective to help clinicians and healthcare researchers make more informed decisions whether reviewing or conducting such a study.


Sample size estimation Prevalence Precision 


Conflict of Interest


Role of Funding Source



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Copyright information

© Dr. K C Chaudhuri Foundation 2012

Authors and Affiliations

  • Ravindra Arya
    • 1
    • 4
    Email author
  • Belavendra Antonisamy
    • 2
  • Sushil Kumar
    • 3
  1. 1.Comprehensive Epilepsy Centre, Division of NeurologyCincinnati Children’s Hospital Medical CentreCincinnatiUSA
  2. 2.Department of BiostatisticsChristian Medical CollegeVelloreIndia
  3. 3.Division of Basic and Translational Research, Department of SurgeryUniversity of MinnesotaMinneapolisUSA
  4. 4.MLC 2015, Cincinnati Children’s Hospital Medical CentreCincinnatiUSA

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