Therefore, in qualitative studies is it critical that data collection and analysis are occurring simultaneously so that the researcher will know when the saturation point is reached. It is important to understand that the saturation point may occur prematurely if the researcher has a narrow sampling frame, a skewed analysis of the data, or poor methodology.
Because of this, the researcher must carefully create the research question, select an appropriate target group, eliminate his or her own biases and analyze data continuously and thoroughly throughout the process to bring validity to the data collected.
The following slideshare presentation, Collecting Qualitative Data , and the Resource Links on this page provide additional insight into qualitative sampling. Qualitative Research Methods - A Data Collectors Field Guide - This comprehensive, detailed guide describes various types of sampling techniques and provides examples of each, as well as pros and cons.
Qualitative Research Overview - The following link provides a full overview of qualitative research, but also contains sections discussing types of sampling methods and methods of participant recruitment. Sampling - This resource provides a brief overview of sampling and sample size with links to descriptions of purposeful sampling strategies. A Guide to Using Qualitative Research Methodology - The file linked below contains a full description of how to conduct qualitative sampling, including a chart that lists the types of sampling techniques and includes examples.
Sampling Designs in Qualitative Research - The following article discusses sampling designs and ways to make the sampling process more public. This pin will expire , on Change. This pin never expires. Select an expiration date. About Us Contact Us. Search Community Search Community. Qualitative Sampling Methods The following module describes common methods for collecting qualitative data. Describe common types of qualitative sampling methodology. Explain the methods typically used in qualitative data collection.
As the research progresses and the researcher studies the same group or different sub-groups, he then arrives at few categories, which on saturation generate his theory. Initially, theoretical sampling is used only for a pragmatic purpose of generating a theory. The ability to generate an extensive understanding of a completely well theory defined in any field through research takes in the account of theoretical sampling. It first focuses on the problem area and then into the various approaches that need the basis of grounded theory.
For example, how confident men handle prospective marks or how policemen act toward people of African descent or what happens to students in medical school that turns them into doctors, is dependent on the theoretical framework that the researcher arrives with.
According to Glaser and Holton , Grounded theory that has a data collecting inclination towards theoretical sampling was first derived from qualitative sampling. Theoretical sampling methods are now considered as the diluted version of grounded theory that is now used in health care research where researcher may want to find out the different reasons for a particular illness to trigger in a particular kind of population.
Also, the selection criteria of participants for theoretical sampling changes according to the needs and changes that occur in the theoretical study at the given time. Theoretical sampling is considered to be purpose driven and it explicitly carries out its function on the basis of an emerging theory.
The concept of saturation was first defined in the context of grounded theory as theoretical saturation. In qualitative research the word saturation is extensively used almost interchangeably with data saturation, thematic saturation, theoretical saturation and conceptual saturation. Saturation can be simply defined as data satisfaction. It is when the researcher reaches a point where no new information is obtained from further data. Saturation point determines the sample size in qualitative research as it indicates that adequate data has been collected for a detailed analysis.
However, there are no fixed sizes or standard tests that determines the required data for reaching saturation. For example, in many phenomenographic studies, theoretical saturation is often reached after 15 to 30 participants,  whereas other methods may require far fewer, or greater, numbers.
An example of theoretical sampling is best described by Glaser and Strauss in the s. I wished first to look at services that minimized patient awareness and so first looked at premature baby service and then a neurosurgical service where patients were frequently comatose.
I wished next to look at dying in a situation where expectancy of the staff was great and dying was quick, so I observed on an Intensive Care Unit. Then I wished to observe on a service where staff expectations of terminality were great but where patients might or might not be, and where dying tended to be slow. So I looked next at a cancer service. I wished then to look at conditions where death was unexpected and rapid, and so looked at an emergency service.
While we were looking at some different types of services, we also observed the above types of serviced at other types of hospitals. So, our scheduling of types of services was directed by a general conceptual scheme- which included hypotheses about awareness, expectedness and rate of dying- as well as by a developing conceptual structure including matters not at first envisioned.
Sometimes we returned to services after the initial two or three or four weeks of continuous observation, in order to check upon items which needed checking or had been missed in the initial period. From Wikipedia, the free encyclopedia. British Journal of Management.
Strategies for Qualitative Research, Retrieved from " https: In Theoretical Sensitivity Glaser sought to address this same concern, and thirty years later this remains to be a notable problem. Purposeful sampling is defined as the selection of participants with shared knowledge or experience of the particular phenomena identified by the researcher as a potential area for exploration Sandelowski Typically, to ensure selection of the most information rich participants, the researcher will establish a set of inclusion or exclusion criteria based upon research questions generated deductively from prior knowledge of the area and a preliminary review of related literature.
The concern is with who or what to sample for the purpose of answering questions about a predetermined topic. In contrast, the selection of participants in theoretical sampling, and the reason underpinning that selection, will change in accordance with the theoretical needs of the study at any given time Morse While a purposeful sample is selected at the outset of the study for a predetermined purpose, theoretical sampling progressively and systematically tailors data collection to serve the emergent theory.
Theoretical sampling is thus always purpose-driven; the sample is selected for the purpose of explicating and refining the emerging theory. It has been clearly established that theoretical sampling is guided by the emerging theory, and is concerned with where to sample next and for what theoretical purpose. Yet for novice researchers newly embarking upon a grounded theory study, the most pressing practical concern is perhaps where to start.
Furthermore, if the purpose of theoretical sampling is to seek data that will contribute to developing categories of the emerging theory, the researcher must surely first have the beginnings of a theory — some tentative ideas — upon which to build. Evidently there is an unavoidable need to begin somewhere. In this sense theoretical sampling may involve the purposeful selection of an initial starting point before moving into theoretical sampling when data analysis begins to yield theoretical concepts.
It is pertinent to remember that the starting point is only that, and the researcher should avoid formulating a preconceived conclusion that these initially sampled characteristics will contribute to theoretical variation Glaser For example, to sample only according to demographic characteristics is to deduce that they will be relevant to the emerging theory Glaser ; Morse However, because points of departure such as demographic characteristics have not emerged from the theory, they must be considered merely another variable awaiting a verdict as to its relevance.
Indeed, descriptive data may be elevated into abstract theory only by way of comparing theoretical categories and properties, not mere demographic opposites Hood Pre-existing knowledge can guide the researcher in identifying a starting point for data collection, but this knowledge should be awarded no relevance until validated or dismissed by the formulation of the emerging theory. In the same way as ideas must earn a way into the theory, the converse is also true; it is possible that initial ideas will earn a way out.
For the novice grounded theorist, the initial concern about where to start is often accompanied by a similar concern regarding the decision to stop data collection. Given the inductive nature of theory generation, it is understood that theoretical sampling, including the point at which sampling will cease, is controlled throughout the study by the emerging theory.
While this definition carries a degree of simplicity, theoretical saturation can be a difficult concept to understand, particularly for first-time grounded theorists who are yet to actually experience reaching the saturation point within a study. While the qualitative researcher seeks descriptive saturation, the grounded theorist is concerned with saturation at a conceptual level.
Theoretical saturation is not mere descriptive redundancy. Instead, theoretical sampling does not aim for full descriptive coverage, but systematically focuses and narrows data collection in the service of theoretical development.
In so doing, the grounded theorist is able to transcend the descriptive level typical of qualitative research. By saturating categories that seem to have the most explanatory power and integrating these into and around a core variable, the grounded theorist is able to present the theoretical essence of a substantive area.
While the saturation point indicates theoretical stability whereby the core category accounts for as much variation in the data as possible, it is crucial to understand that these concepts and hypotheses are openly modifiable within the substantive area.
Saturation in classic grounded theory is thus neither concerned with verifying hypotheses or exhausting the description of a particular situation at a particular point in time. Instead, the researcher should be concerned with generating a theory that can cope with changing situations a particularly important consideration within the ever-changing healthcare arena and less with in-the-moment accuracy that has little temporal transferability. From a grounded theory perspective, however, there lies an inherent risk in the excessive description of potentially irrelevant detail.
This is of particular concern in relation to the above discussion, whereby researchers should not automatically assume the relevance of participants socio-demographic characteristics to the emerging theory.
While demographic or social characteristics may provide a starting point for data collection, by presenting a thick, isolated description of participants at the start of a grounded theory research article the researcher is at risk of either belying an inappropriate approach to sampling, or obscuring the analytic flow and progression of theoretical insights thus compromising the credibility of an otherwise trustworthy study.
Morse has criticised the way in which theoretical samples are presented as static without detailing and justifying the selection and sequencing of the sampling process.
Typically, researchers provide a one-off description of participants in the methods section of research articles, and ignore the impact of sampling decisions made during analysis Barbour However, if the researcher does not capture the flow of the theoretical sampling process, the complexities involved in the development of the theory may be lost. Theoretical sampling is intertwined inextricably with the abstraction of description into theory, and is crucial to discovering and refining categories and their properties and suggesting relationships between concepts.
Studies that produce an artificially neat and static account of the grounded theory process serve only to obscure this complexity Barbour Novice grounded theorists should be careful to write-up a grounded theory study in a manner that best reflects the methodology.
Grounded theory researchers should avoid isolated, one-off, static descriptions of participants but should instead be challenged to integrate within their write up the progression, justification and contribution of sampling decisions so as to mirror the complex and iterative process of theory development. Theoretical sampling is theoretically oriented, and will thus be different for every theory. There is no definitive checklist for ensuring credibility, and the reader should be careful when applying conventional guidelines of trustworthiness in qualitative research to grounded theory studies.
For example, the emphasis on thick description in qualitative research has been demonstrated to be potentially antithetical to the inductive nature of grounded theory; sampling should be theoretically directed as opposed to variable oriented and only those descriptive characteristics that have a proven contribution to theoretical variation within the theory should be included in the write up.
Theoretical sampling is associated with grounded theory approach based on analytic induction. Theoretical sampling is different from many other sampling methods in a way that rather than being representative of population or testing hypotheses, theoretical sampling is aimed at generating and developing theoretical data. Theoretical sampling .
dierences between purposeful and theoretical sampling for nursing research. Keywords: sampling, qualitative, grounded theory sample size in order to ensure representativeness and INTRODUCTION the qualitative principle of appropriateness that requires Sampling procedures in qualitative research are not so purposeful samplingand a ‘‘good’’ .
In theoretical sampling the researcher manipulates or changes the theory, sampling activities as well as the analysis during the course of the research. Flexibility occurs in this style of sampling when the researchers want to increase the sample size due to new factors that arise during the research. The goal of qualitative research is to provide in-depth understanding and therefore, targets a specific group, type of individual, event or process. To accomplish this goal, qualitative research focus on criterion-based sampling techniques to reach their target group.
Qualitative research is designed to explore the human elements of a given topic, while specific qualitative methods examine how individuals see and experienc Theoretical sampling is a tool that allows the researcher to generate theoretical insights by drawing on comparisons among samples of data. First of all, both theoretical sampling and snowball sampling correspond to what is usually called "sampling strategies" in qualitative research. 1) Theoretical sampling makes up the classical.