What about N? A methodological study of sample-size reporting in focus group studies

Area of Science:

• Health research methodology
• Qualitative research methods

Background:

• Focus group studies are increasingly common in health journals.
• Methodological guidance on determining sample size, particularly data saturation, is lacking.
• Understanding researcher practices in sample size determination for focus groups is crucial.

Purpose of the Study:

• To describe current sample size reporting in health-related focus group studies.
• To assess how researchers explain their choice of focus group numbers.
• To identify gaps in methodological reporting and guidance.

Main Methods:

• PubMed search for open-access focus group studies published in 2008.
• Data extraction on the number of focus groups and explanations provided.
• Qualitative assessment of the reporting and discussion of sample size.

Main Results:

• 220 papers were analyzed; insufficient sample size reporting was prevalent.
• The number of focus groups varied widely (median 5, range 1-96).
• Only 17% of studies explained their sample size; explanations often lacked methodological rigor.

Conclusions:

• Journals should implement stricter reporting requirements for focus group methodology.
• Lack of clear, evidence-based guidance contributes to poor sample size reporting.
• Further empirical research is necessary to advance focus group methodology and sample size determination.