In qualitative research, validity is conceptualized as trustworthiness rather than internal/external validity, encompassing credibility (confidence in findings), transferability (applicability to other contexts), dependability (consistency of procedures), and confirmability (findings grounded in data rather than researcher bias). Strategies for establishing trustworthiness include prolonged engagement, persistent observation, triangulation, member checking, and reflexivity—examining researcher biases and how the researcher influences findings. Unlike quantitative research where representative samples support statistical generalization, qualitative research emphasizes thick description and purposeful sampling to support transferability. Establishing trustworthiness is essential for evaluating qualitative research quality.
Design trustworthiness strategies (member checking, triangulation, reflexive notes) for a qualitative study plan.
Qualitative research cannot be evaluated for quality (actually, trustworthiness criteria provide rigorous standards). Reflexivity means eliminating researcher influence (actually, it means acknowledging and documenting how the researcher influences the research).
From your work on qualitative data analysis, you've learned to code interview transcripts, develop themes, and build interpretive accounts of participants' experiences. The natural next question is: how do you know if that account is good? In quantitative research, quality criteria like internal validity and reliability have well-established operationalizations (random assignment, test-retest coefficients, inter-rater agreement). But these concepts don't map cleanly onto qualitative work, where the goal isn't replication or elimination of researcher influence — it's producing a rich, contextualized understanding of a particular phenomenon. Lincoln and Guba's framework of trustworthiness offers parallel criteria designed for qualitative logic rather than borrowed from quantitative standards.
The four trustworthiness criteria correspond to quantitative parallels but with different operationalizations. Credibility (analogous to internal validity) asks: are the findings an accurate representation of participants' realities? The primary strategy is member checking — returning interpretations to participants to verify they recognize their experience in your account. Prolonged engagement (spending sufficient time in the field to build genuine understanding) and triangulation (checking findings against multiple data sources, methods, or investigators) also support credibility. Transferability (analogous to external validity) doesn't mean statistical generalization from sample to population — that's not what qualitative studies claim. Instead, it refers to whether findings might apply to other contexts. The researcher's responsibility is to provide thick description — detailed, contextually rich accounts of the setting, participants, and phenomena — so that readers can judge for themselves whether the findings are relevant to their situations.
Dependability (analogous to reliability) asks whether the research process is consistent and traceable. An audit trail — documentation of data, analytic decisions, and methodological choices — allows an external reviewer to evaluate whether the process was coherent and defensible. Dependability doesn't require that two researchers would produce identical findings (they won't, and that's appropriate), but that the process is transparent and its logic is followable. Confirmability (analogous to objectivity) asks whether findings are grounded in data rather than driven by researcher preconceptions. Here reflexivity is the central strategy — not eliminating researcher influence, which is impossible, but systematically acknowledging and documenting it. A reflexive researcher keeps a researcher memo tracking their assumptions, reactions, and evolving interpretations, making the subjective dimension of analysis visible and examinable rather than pretending it doesn't exist. Together these four criteria constitute a rigorous framework for evaluating qualitative work on its own terms.