This document discusses reliability and validity in qualitative research and handling qualitative data. It covers key concepts like purposive sampling, theoretical sampling, and snowball sampling. It also discusses alternative criteria for evaluating qualitative research reliability and validity, including credibility, transferability, dependability, and confirmability. These criteria parallel internal validity, external validity, reliability, and objectivity in quantitative research. The document provides explanations and examples of each criteria.

1. Reliability and validity in qualitative
research and handling qualitative data
examples
Dr. Branly Mbunga
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2. Sampling
 Quantitative research relies upon probability
sampling in order to be able to generalise results to
the wider population.
 Qualitative research has different aims, but sampling
is still an important consideration (see Bryman 2008).
 Purposive sampling – selecting participants based
upon their relevance to the question(s) posed.
 Theoretical sampling – data collection is guided by the
codes, categories and concepts emerging from the data.
 Snowball sampling – initial contact using theoretical
sampling and then get referrals from participants.
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3. Reliability
 In quantitative research a reliable measure is one
which produces the same response to a question.
 Allows for replication of previous studies – e.g.
measuring party identification over time.
 In qualitative research our goals are different,
however we can re-conceptualise the concept of
reliability in order to produce good social
research.
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4. Reliability (LeCompte and Goetz 1982)
 External reliability – can the study be repeated? If
you are replicating a previous study, adopt similar
role to previous researcher.
 Internal reliability – when there is more than one
observer all should agree on what is seen and
heard.
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5. Alternative criteria for qualitative research (Guba
and Lincoln, 1994; Lincoln and Guba, 1985)
 Trustworthiness – four criteria (see Bryman, 2008)
 Credibility – parallel of internal validity
 Transferability – parallel of external validity
 Dependability – parallel of reliability
 Confirmability – parallel of objectivity
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6. Credibility
 Acknowledges there are multiple accounts of
social reality.
 Credible research is that which has been carried
out according to best practices and peer-review.
 Goal is to confirm the social researcher correctly
understood the social world.
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7. Transferability
 Qualitative research illuminates the contextual
uniqueness of their object of inquiry.
 Instead of holding to quants standards of external
validity, Lincoln and Guba recommend producing
thick description of a culture/setting/etc.
 Thick description can assist in the determination
of whether findings are valid in other situations
(e.g. Consider transferability of Tower Hamlets
findings vs. brief interventions from last week)
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8. Dependability
 Dependability – parallel of reliability
 An “auditing” approach to research
 Detail work phases (research question, sampling,
data collection, field notes, transcripts, methods
of data analysis planned)
 Peer review
 Not wide spread. High demands on auditors.
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9. Confirmability
 Aims for ‘objectivity’ – being a neutral observer
of events – is impossible given the qualitative
epitsemology.
 Instead confirmability is concerned with ensuring
the researcher has acted in good faith.
 Research and finding have not been overtly swayed by
personal values
 Confirmability should be a criteria for auditors or
peer review.
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