Glaser, Barney G & Strauss, Anselm L., 1967. The Discovery of Grounded
Theory: Strategies for Qualitative Research, Chicago, Aldine Publishing
This book is about discovering theory from data, what Glaser and Strauss
call grounded theory. The major strategy they use is a general method of
comparative analysis. They argue that much of current research is primarily
the verification of theory or the development of theory through logical
deduction rather than from the experimental data itself.
In sociology they propose that the roles of theory is to:
* to enable prediction and explanation of behavior
* to be useful in theoretical advance
* useable in practical applications
* guide research on behavior.
"Theory is sociology is a strategy for handling data in research, providing
modes of conceptualization for describing and explaining" (p. 3).
Basing theory on experimental data ties it to the data and makes it irrefutable.
It reduces the opportunitistic use of available theories or the force fit
of popular theories to the data. It avoids "exampling", the often
easy task of finding examples to fit any theory.
Glaser and Strauss take the position that the adequacy of a theory can't
be divorced from the process of creating it (p. 5). The purpose of their
book is to describe a method and some tips on how to build theory out of
Verification and Grand Theory
Most research today is designed to verify existing theories, not generate
new ones. Researchers eek out small gains of knowledge from existing "grand
theories" rather than explore new areas not covered by existing theories.
The existing research culture emphasizes and reveres good scientific, quantitative
verification studies and downplays more qualitative studies whose objective
is theory generation. Most theory is thus generated through logical deduction
from past studies and knowledge and not from the data itself.
Part I: Generating Theory By Comparative Analysis
In comparative analysis different groups or subgroups of people are compared
and their differences build into theory. The theory is then tested and
refined by considering it with other comparision groups. Looking at the
data we begin to ascertain patterns in the data/behavior which can lead
to general concepts about it. These concepts can then be built into broader
theoretical propositions which can then be evaluated and tested with other
"In discovering theory, one generates conceptual categories or their
properties from evidence, then the evidence from which the category emerged
is used to illustrate the concept" (p. 23). These conceptual categories
can then be explored in other comparison groups, which may support the categorical
concept or suggest modifications to make it more generalizable.
In the pure pursuit of theory generation accurate evidence and verification
are not that important, but often researchers get caught up in these two
areas (because they are part of the current reward system) and thus limit
the possibilities and narrow their range of potential theory generation.
Theory generation doesn't require lots of cases. One case could be used
to generate conceptual categories and a few more cases used to confirm the
indication (p. 30). "(The reseacher's) job is not to provide a perfect
description of an area, but to develop a theory that accounts for much of
the relevant behavior" (p. 30).
What Theory is Generated
Grounded theory can appear in various forms. "Grounded theory can
be presented either as a well-codified set of propositions or in a running
theoretical discussion, using conceptual categories and their properties"
(p. 31). The authors prefer the discussional form, because it is often
easier to comprehend and tends not to "freeze" the theory in a
set of propositions.
Comparative analysis can generate two types of theory -- substantive and
formal. Substantitive theory is developed for a specific area of inquiry,
such as patient care, professional education, delinquency, etc. Formal
theory is for a conceptual area of inquiry such as stigma, deviant behavior,
formal organization, socialization, reward systems, etc.
It is often best to begin with generating substantive theory from data and
then let formal theory or revisions to existing formal theory emerge from
substantive theory instead of using logic to deduce substantive theory from
formal theory. More studies generating substantive theory will ultimately
generate and improve formal theory.
Elements of the Theory
The elements of theory generated from comparative analysis are first conceptual
categories and their properties and second hypotheses or generalized relations
among the categories and their properties. "The constant comparing
of many groups draws the sociologist's attention to their many similarities
and differences. Considering these leads him to generate abstract categories
and their properties, which, since they emerge from the data, will clearly
be important to a theory explaining the kind of behavior under observation"
(p. 36). It's best to let the categories emerge than to come into the
study with pre-set categories based on existing theories.
"An effective strategy is, at first, literally to ignore the literature
of theory and fact on the area under study, in order to assure that the
emergence of categories will not be contaminated by concepts more suited
to different areas" (p. 37).
They also advocate that the generation of theory should initially aim at
acheiving high diversity in emergent categories, at as many levels of conceptual
and hypothetical generalization as possible. The concepts should be analytic
and yet sensitizing, giving the ability to grasp references in terms of
one's own experience.
Generating hypotheses from the data requires only enough data to suggest
the hypothesis, not prove it.
During the research the emergent categories will begin to form patterns
and interrelations which will ultimately form the core of the emerging theory
Chapter Three: Theoretical Sampling
Building grounded theory requires an interative process of data collection,
coding, analysis, and planning what to study next. The researcher needs
to by theoretically sensitive as they are collecting and coding data to
sense where the data is taking them and what to do next. Coming into a
research program with an existing theoretical framework will merely blind
them to the richness of the incoming data.
As this iterative process continues, the researcher may explore the same
group more deeply or in different ways, or may seek out new groups. Comparison
groups should be selected based on their theoretical relevance to further
the development of emerging categories. It's best to pick the groups as
you go along than choose them all beforehand -- let the data be your guide.
In theory generation non-comparability of groups is irrelevant, but it
can have an effect on the level of substantive theory developed and it's
thus important to pick the right group for the next part of the comparative
Sometimes it's best to pick similar groups to gain sensitivity to differences
between groups and to estabilish a definite set of conditions when a category
will exist. Other times its best to pick very different groups which will
maginify the strategic similarities and broaden the scope of the emergent
theory. The researcher takes the role of an active sampler, pursuing leads
and groups without worrying about being incomplete.
The researcher will know when a given search is ended or the appropriate
number of groups surveyed when no additional data can be found that develops
properties of the conceptual categories. The researcher can saturate on
category and then move on to other categories. "In trying to reach
saturation he maximizes differences in his groups in order to maximize the
varieties of data bearing on the category, and thereby develops as many
diverse properties of the category as possible" (p. 62). Core theoretical
categories should be saturated more than peripheral ones.
Theoretical sampling is not statistical sampling -- it may only require
a few groups to exhaust one category, and many groups to exhaust another.
The number of groups is based on the extent of saturation and the level
of theory one wants to generate. Knowing when to quit is a skill developed
Theory generation can involve multiple types of data simultaneously, and
multiple slices of that data. Often it doesn't matter what slices the researcher
uses -- they all are useful in developing categories. In fact , multiple
slices helps build better theory by ensuring the generated theory works
from multiple perspectives.
IV: From Substantive to Formal Theory
One way to generate formal theory from substantive theory is merely to replace
specific words with general words and see what happens. Another way is
to apply the substantive theory to more diverse groups and situations and
interatively expand the substantive theory. Another method is through direct
comparisons of data from other substantitive areas in the researchers experience
or in the literature, though this is risky and often leads to logical-deductive
Most researchers tend to stay in the substantive theory area and avoid going
into formal theory.
V: The Constant Comparative Method of Qualitative Analysis
Currently analyzing qualitative data usually involves coding the data to
get some quantifiable means to test some hypotheses. Glaser and Strauss
advocate combining coding with analysis to help locate and build grounded
In this method the data is coded only enough to generate categories and
hypotheses. The authors describe four main stages:
1. Comparing incidents applicable to each category
Begin by coding the data into as many categories as possible. Some categories
will be generated from himself, some from the language and data of the research
situation. As you find more instances of the same category code you will
being to refine your ideas about that category. At this point it's best
to stop coding and record a memo of these ideas.
2. Integrating Categories and their Properties
The constant comparative method will begin to evolve from comparing incidents
to focusing on emergent properties of the category. Diverse properties
will start to become integrated. The resulting theory will begin to emerge
3. Delimiting the Theory
Eventually the theory solidifies, and there are fewer changes to the theory
as the researcher compares more incidents. Later modifications include
taking out irrelevant properties of the categories, integrating details
of properties into an outline of interrelated categories. More importantly,
the researcher will begin to find ways to delimit the theory with a set
of higher level concepts. He/she will find ways to generalize the theory
more as they continue to make constant comparisons against it. The number
of categories will be reduced.
New categories are often created halfway through coding, and it usually
isn't necessary to go back and code for them. You only need to code enough
to saturate the properties of the category. Later you can evaluate your
categories and emergent theory by moving on to new comparison groups.
4. Writing Theory
"When the researcher is convinced that his analytic framework forma
a systematic substantive theory, that is it s reasonably accurate statement
of the matters studied, and that it is couched in a form that others going
into the same field could use -- then he can publish his results with confidence"
This methodology tends to result in a "developmental" theory,
which lends itself to further evolution. It's an inductive rather than
VI: Clarifying and Assessing Comparative Studies
Many types of studies are subsumed under the general name of comparative
analysis. Each has differing objectives regarding generation and verification,
and you must carefully read them to determine what level of each the study
VII: New Sources for Qualitative Data
Glaser and Strauss advocate using the library to supplant field data in
theory generation. The strategies used in library research can be very
similar to those previously discussed for fieldwork. Most researchers underutilize
the library and overfocus on their own research data.
There are many types of primary and secondary documents that can be interatively
explored like fieldnotes and can be coded as well. There may be sets of
interviews, surveys, pictures that prove useful in theory generation or
in further explaining the fieldnote contexts. The library offers a fantastic
range of potential comparison groups to study.
Of course, the library strategy has limitations. Existing data may be quite
limited in scope. Further clarification may be impossible (especially if
the respondents are dead). It can be hard to assess accuracy.
VIII: Theoretical Elaboration of Quantitative Data
Even quantitative data, often the exclusive domain of verification studies,
can be used to generate grounded theory. The authors propose that this
could be a new frontier of theory generation.
IX: The Credibility of Grounded Theory
Often qualitative research of this type is labeled "sloppy" or
"exploratory". You can improve the credibility by basing your
research on multiple comparison groups.
X: Applying Grounded Theory
A good pratical ground theory should:
* fit the substantive area it will be used in* understandable by laymen
in that area
* general enough to apply to many situations in the area
* allow the user some control over the theory as the daily situations change