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Updated: Jun 4, 2026

Sampling Soils in a Heterogeneous Research Plot
Published on: January 7, 2019
[Sampling in qualitative research: a proposal for procedures to detect theoretical saturation]
Bruno Jose Barcellos Fontanella1, Bruna Moretti Luchesi, Maria Giovana Borges Saidel
1Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, Rodovia Washington Luís km. 235, São Carlos, SP, Brazil. bruno@ufscar.br
Abstract:
A qualitative study's methodological transparency is considered a key factor for achieving its reliability and should be guaranteed by the researchers. Closing the sampling process by saturation is a common approach, but it is rarely made explicit in research reports. Qualitative researchers also commonly experience technical difficulties in objectively identifying saturation. This article proposes a method to organize sample closing by saturation, with a sequence of eight procedural steps for treating and analyzing data collected through open or semi-structured interviews or focus groups. The article aims to help researchers objectively explain how and when saturation occurred and to allow their readers to know how this process occurred.
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