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Updated: Aug 19, 2026

Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Determination of the population size in an epidemiological study with children
G Ihorst1, J Forster, G Petersen
1Institute of Medical Biometry and Medical Informatics, University Hospital of Freiburg, Stefan-Meier-Str. 26, 79104 Freiburg, Germany. gabi@imbi.uni-freiburg.de
Insights
Estimating pediatric population size for incidence studies is crucial. Using well-baby visits provides a reliable method, though exact figures are preferred for accuracy in epidemiological research.
Area of Science:
- Epidemiology
- Pediatrics
- Population Health
Background:
- Accurate population size estimation is vital for epidemiological studies, particularly for incidence calculations.
- Pediatric practices serve as key sites for monitoring child health and disease patterns.
Purpose of the Study:
- To determine a reliable method for estimating the population size of children in a pediatric practice for epidemiological studies.
- To assess the accuracy of using well-baby visit data for population estimation.
Main Methods:
- Utilized the number of regularly attended well-baby visits to estimate the pediatric population size.
- Employed data from a prospective study (PRI.DE) on lower respiratory tract infections (LRTI) in Germany.
- Compared estimations with exact practice figures when available.
Main Results:
- Population size estimations using well-baby visits generally showed good fit, with deviations ranging from 11% to 17%.
- In some instances, estimations exhibited poor fit with deviations as high as 60%.
Conclusions:
- Emphasizes the importance of using exact population figures when obtainable for epidemiological studies.
- Highlights the necessity of careful appraisal of estimation results to ensure reliability.
Objectives:
To obtain a reliable estimate of the population size in an epidemiological study concerned with incidence estimation.
Methods:
In the present case, the population of interest consists of all children attending a certain pediatric practice for any reason and is estimated making use of the number of regularly attended well baby visits. In some cases, exact figures from the practices are available as a reference. A prospective epidemiological study on the estimation of the incidence of lower respiratory tract infections (LRTI) in the German pediatric population (PRI.DE, Parainfluenza- und Respiratory-Syncytial-Virus-Infektionen in Deutschland) is used to demonstrate the procedure.
Results:
In most cases, the fit can be regarded as good with deviations between 11% and 17%, whereas in a few cases it must be considered as poor (deviations of 60%).
Conclusions:
The importance of using exact figures whenever obtainable and of appraising the results carefully is emphasized.
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