VALIDITY & RELIABILITY IN QUALITATIVE
Qualitative research is concerned with the systematic
collection, ordering, description and interpretation of
textual data generated from talk, observation or
Qualitative research uses a naturalistic approach that
seeks to understand phenomena in context specific
setting such as “real world setting researcher does not
attempt to manipulate the phenomena of interest”
• (Corbin, 1990) defined qualitative research as “any kind
of research that produces findings not arrived at by
means of statistical procedures or other means of
• The terms reliability and validity are essential criterion
for quality in qualitative paradigm, in qualitative
paradigms the terms Credibility, Neutrality or
Conformability, Consistency or Dependability and
Applicability or Transferability are to be essential criteria
for quality (Lincoln & Guba, 1985).
• To be more specific with term of reliability in
qualitative research, Lincoln & Guba (1985, p.
300) use “dependability”, in qualitative research
which closely corresponds to the notion of
“reliability” in quantitative research. They further
emphasize “inquiry audit” (p. 317) as one
measure which might enhance the dependability
of qualitative research.
• Quantitative research methods include:
interviewing, observation and document
• Validity: is descripted as the degree to which a
research study measures what is intends to.
• Researcher’s generally determine validity by
asking a serious of questions and will often look
for answers in the research of other.
• Validity: determines whether the research truly
measures that which it was intended to or how
truthful the research results are.
• Reliability and validity are conceptualized as
trustworthiness, rigor and quality in qualitative
paradigm. That can be achieved by eliminating
bias and increasing the researcher’s trustfulness of
a proposition about some social phenomena using
Strategies for ensuring trustworthiness
in qualitative research
• Many naturalistic investigators have, however, preferred to use
different terminology to distance themselves from positivism
paradigm. One such author is Guba, who proposes four criteria
that he believes should be considered by qualitative researchers
in pursuit of trustworthy study. By addressing similar issues,
Guba’s constructs correspond to the criteria employed by the
1) Credibility (in preference to internal validity)
2) Transferability (in preference to external validity/
3) Dependability (in preference to reliability)
4) Confirmability (in preference to objectivity )
• one of the key criteria addressed by positivist
researchers is that of internal validity, in which
they seek to ensure that their study measures or
tests what is actually intended. The following
provisions may be made by researchers to
promote confidence that they have accurately
recorded the phenomena under scrutiny:
✔The adoption of research methods well
established both in qualitative investigation in
general and in information science in particular
✔ The development an early familiarity with the culture of
participating organizations before the first data collection
dialogues takes place.
✔ Random sampling of individuals to serve as informants.
✔ Triangulation: triangulation may involve the use of
different methods, especially observation, focus groups
and individual interviews, which form the major data
collection strategies for much qualitative research.
✔ Tactics to help ensure honesty in informants when
contributing: in particular each person who is approached
should be given opportunities to refuse to participate in
the project so as to ensure that the data collection sessions
involve only those who are genuinely willing to take part
and prepared to offer data freely.
✔ Iterative questioning: in addition on the “preventative”
strategies outlined above specific ploys may be
incorporated to uncover deliberate lies.
✔ Negative case analysis
✔ Frequent debriefing sessions between researcher and his
or her superiors, such as a project director or steering
✔ Peer scrutiny of the research project.
✔ Background, qualifications and experience of
✔ The researcher’s “reflective commentary”.
• Erlandson et al. note many naturalistic inquires
believe that, in practice even conventional
generalizability is never possible as all
observations are defined by the specific
contexts in which they occur. A contrasting
view is offered Stake and Denscombe , who
suggest that, although each case may be
unique, it is also an example within broader
group and as a result the prospect of
transferability should not be immediately
• Lincoln, Guba and Firestone suggest that it is
the responsibility of the investigator to insure that
sufficient contextual information about field work
sites is provided to enable the reader to make such
• It is also important that sufficient thick
description of the phenomenon under
investigation is provided to allow readers to have
a proper understanding of it, thereby enabling
then to compare the instances of the phenomenon
described in the research report with those that
they have seen emerge in their situations
Employment of “ overlapping methods”
• Lincoln and Guba stress the close ties between
credibility and dependability, arguing that in
practice a demonstration of the former goes some
distance in insuring the latter. This may be
achieved through the use overlapping methods
such as the focus group and individual interview.
In order to address the dependability issue more
directly, the process with in the study should be
reported in detail, thereby enabling a future
researcher to repeat the work, if not necessarily to
gain the same results.
• 4) Confirmability
• The concept of confirmability is the qualitative
investigator’s comparable concern to objectivity.
Here steps must be taken to help insure as far as
possible that the works findings are the result of
the experiences and ideas of the informants,
rather than the characteristics and preferences of
• The role of triangulation in promoting such
comfirmablity must again be emphasized, in this
context to reduce the effect of investigator bias.
• Miles and Huberman consider that a key criterion
for comfirmability is the extent to which the
research admits his or her own predisposition. To
this end, beliefs underpinning decision made and
methods adopted should be acknowledged within
the research report, the reasons for favoring one
approach when others could have been taken
explained and weaknesses in the techniques
actually employed admitted. In terms of results,
preliminary theories that ultimately where not
borne out by the data should also be discussed.