What is an adequate sample size? Operationalising data saturation for theory-based interview studies

@article{Francis2010WhatIA,
  title={What is an adequate sample size? Operationalising data saturation for theory-based interview studies},
  author={Jillian Joy Francis and Marie Johnston and Clare Robertson and Liz Glidewell and Vikki A. Entwistle and M. Eccles and Jeremy M. Grimshaw},
  journal={Psychology \& Health},
  year={2010},
  volume={25},
  pages={1229 - 1245}
}
In interview studies, sample size is often justified by interviewing participants until reaching ‘data saturation’. However, there is no agreed method of establishing this. We propose principles for deciding saturation in theory-based interview studies (where conceptual categories are pre-established by existing theory). First, specify a minimum sample size for initial analysis (initial analysis sample). Second, specify how many more interviews will be conducted without new ideas emerging… Expand
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