Sampling IIBMJ 2010; 340 doi: https://doi.org/10.1136/bmj.b5677 (Published 07 January 2010) Cite this as: BMJ 2010;340:b5677
- Philip Sedgwick, senior lecturer in medical statistics
- 1Centre for Medical and Healthcare Education, St George’s, University of London, Tooting, London SW17 0RE
Using a cross-sectional survey, researchers investigated the body weight patterns of adults living in Tirana City, Albania.1 To obtain a representative sample, the city was divided into 256 zones on the basis of map divisions, of which 58 were randomly selected. In each of the selected zones, 12 households with two or more inhabitants aged 25 years or over were randomly selected. Two adults from each household were invited to participate.
Which of the following terms best describes the sampling method used in the above study?
a) Cluster sampling
b) Multistage sampling
c) Convenience sampling
d) Proportional quota sampling
b—Multistage sampling entails several stages of random sampling based on the hierarchical structure of natural clusters of individuals within the population. Examples of natural clusters include towns and cities, schools, general practices, streets, and households. A different type of cluster is sampled at …