No abstract

Data saturation is the most commonly employed concept for estimating sample sizes in qualitative research. Over the past 20 years, scholars using both empirical research and mathematical/statistical models have made significant contributions to the question: How many qualitative interviews are enough? This body of work has advanced the evidence base for sample size estimation in qualitative inquiry during the design phase of a study, prior to data collection, but it does not provide qualitative researchers with a simple and reliable way to determine the adequacy of sample sizes during and/or after data collection. Using the principle of saturation as a foundation, we describe and validate a simple-to-apply method for assessing and reporting on saturation in the context of inductive thematic analyses. Following a review of the empirical research on data saturation and sample size estimation in qualitative research, we propose an alternative way to evaluate saturation that overcomes the shortcomings and challenges associated with existing methods identified in our review. Our approach includes three primary elements in its calculation and assessment: Base Size, Run Length, and New Information Threshold. We additionally propose a more flexible approach to reporting saturation. To validate our method, we use a bootstrapping technique on three existing thematically coded qualitative datasets generated from indepth interviews. Results from this analysis indicate the method we propose to assess and report on saturation is feasible and congruent with findings from earlier studies.

Few empirical studies exist to guide researchers in determining the number of focus groups necessary for a research study. The analyses described here provide foundational evidence to help researchers in this regard. We conducted a thematic analysis of 40 focus groups on health-seeking behaviors of African American men in Durham, North Carolina. Our analyses revealed that more than 80% of all themes were discoverable within two to three focus groups, and 90% were discoverable within three to six focus groups. Three focus groups were also enough to identify all of the most prevalent themes within the data set. These empirically based findings suggest focus group sample sizes that differ from many of the ''rule of thumb'' recommendations in the existing literature. We discuss the relative generalizability of our findings to other study contexts, and we highlight some methodological questions about adequate sample sizes for focus group research.

Objective To describe fertility patients' preferences for disposition of cryopreserved embryos and determine factors important to these preferences Design Cross-sectional survey conducted between June 2006 and July 2007 Setting Nine geographically diverse U.S. fertility clinics Participants 1020 fertility patients with cryopreserved embryos Interventions Self-administered questionnaire Main Outcome Measures Likelihood of selecting each of five conventional embryo disposition options: store for reproduction, thaw and discard, donate to another couple, freeze indefinitely, and donate for research; likelihood of selecting each of two alternative options identified in previous research: placement of embryos in the woman's body at an infertile time, and a disposal ceremony; importance of each of 26 considerations to disposition decisions; and views on the embryo's moral status. Results 54% of respondents with cryopreserved embryos were very likely to use them for reproduction, 21% were very likely to donate for research, 7% or fewer were very likely to choose any other option. Respondents who ascribed high importance to concerns about the health or well-being of the embryo, fetus, or future child were more likely to thaw and discard embryos or freeze them indefinitely. Conclusions Fertility patients frequently prefer disposition options not available to them or find available options unacceptable. Restructuring and standardizing the informed consent process and ensuring availability of all disposition options may benefit patients, facilitate disposition decisions and address problems of long term storage.

Genotype-Driven Recruitment is a potentially powerful approach for studying human genetic variation but presents ethical challenges. We conducted in-depth interviews with research participants in six studies where such recruitment occurred. Nearly all responded favorably to the acceptability of recontact for research recruitment, and genotype-driven recruitment was viewed as a positive sign of scientific advancement. Reactions to questions about the disclosure of individual genetic research results varied. Common themes included explaining the purpose of recontact, informing decisions about further participation, reciprocity, “information is valuable,” and the possibility of benefit, as well as concerns about undue distress and misunderstanding. Our findings suggest contact about additional research may be least concerning if it involves a known element (e.g., trusted researchers). Also, for genotype-driven recruitment, it may be appropriate to set a lower bar for disclosure of individual results than the clinical utility threshold recommended more generally.