Purposeful Sampling and Saturation
Qualitative research is fundamentally framed by a research problem which is the need for the research, a research purpose which reflects the intent, idea, or objective underlying a study, and the research questions which constitute questions that the data gathering will help to answer (Creswell, 2009). In qualitative research, data gathering or sampling strategy to answering research questions is by two means or sources-site and participant (Maxwell as cited in Ravitch & Carl, 2016) since in essence, the research problem initiates the study whiles the study purpose and study questions inform the sampling strategy (Creswell, 2009). The ensuing discussion is designed towards critiquing the sampling strategy employed by Yob & Brewer (n.d.) vis-a-vis the article under review.
Research Purpose, Research Questions, and Research Site
An exemplary research purpose entails ideas about the research participant and sites and details about the central phenomenon being explored (Creswell, 2009). A qualitative research purpose also reflects an evolving or developing design and the use of words from a qualitative research vocabulary (Schwandt as cited inCreswell, 2009). Developing their research from the problem of lack of references for understanding missionary activities regarding “online and geographically dispersed programs” (Yob and Brewer, p. 3) Yob and Brewer’s (n.d.) intention was to innovate references of understanding aimed at helping towards the facilitation of curriculum and student study and service initiatives development regarding positive social change. Yob and Brewer’s (n.d.) research purpose vis-à-vis purpose statement invariably entailed ideas of research participants namely members of the university (faculty, students, and alumni), of a distance learning university involved in positive social change initiatives (site), and details of the central phenomenon, which is understood as an institution of higher education’s “mission of creating positive social change…. defined as the reaching out to their neighborhoods as a member of the community to contribute to the common good through research, service, and educational opportunities” (Yob & Brewer, n.d., p. 2).
Although research questions are central to qualitative research in that they are used to guide the research (Ravitch & Carl, 2016) the authors notably, did not explicitly state their research questions. Thus, a reader needs to deduce from the interview questionnaires, codes, and themes or answers to get the import of how the author understood or explained the problem.
Researchers Purposeful Sampling Strategy
A purposeful sampling strategy constitutes the selection of: respondents for a study based on their identity as having study related knowledge of study phenomenon and resides within the site of the study; site; and so forth (Ravitch & Carl, 2016). Yob and Brewer (n.d.) sort to help universities innovate curriculum in the direction of developing student’s effort towards positive social change by providing references of understanding regarding positive social change based on prevailing meanings and practices surrounding positive social change activities. In order to create meanings of positive social change mission or efforts to provide the references of understanding and hence themes of positive social change to augment the lack thereof in scholarship and practice, Yob and Brewer (n.d.) adopted a purposeful sampling strategy that fundamentally the involved the selection of thirty individuals of the university with backgrounds in positive social change activities or identified to have participant experiences in positive social change activities. Yob and Brewer (n.d.) also adopted a site-a distance learning institution that characterizes among many the primacy of online and a geographic dispersing of the individual. Details of Yob and Brewer’s (n.d.) study, however, were not illuminating enough to warrant a clear definition of the purposeful sampling strategy. Notwithstanding, with the understanding that “multiple strategies can be used to achieve purposeful sampling strategy” (Ravitch & Carl, 2016, p. 128) the above details indicate that the authors’ purposeful sampling strategy best reflects the combined characteristics of the “instrumental-use multiple-case sampling” (Ravitch & Carl, 2016, p. 134) and “key informants, key knowledgeable, and reputationalsampling” (Ravitch & Carl, 2016, p. 134) where cases are chosen towards the development of generalizable finding to facilitate the enactment policy, program, and practice changes and individuals are selected based on knowledge, reputational influence to provide insight and clarity regarding the issues being inquired about (Ravitch & Carl, 2016) respectively.
Alternative Data Collection Strategy
Data collection in qualitative research is a process characterized by relatedness and iterations involving the generation and coconstruction of data (Ravitch & Carl, 2016). Thus qualitative data collection strategy should be dynamic in combining elements of interviews, surveys, focus groups, observation fieldnotes, archival and participants generated documents and media, and researcher memos and journals (Ravitch & Carl, 2016). Aside from generating data from mainly, interviews via telephones vis-à-vis transcriptions and observations, Yob and Brewer (n.d.) could have enhanced the dynamic or multidimensional nature of the process by infusingcoconstructive and generational methods that involves focus group interview, reflexivity, memos, contact summary forms, research logs towards achieving complexity and richness. The lack of these generative and coconstructive in the authors’ data generation strategy explains the limit in richness and complexity of the study.
Evaluation of Researchers’ Data Saturation Approach
Data saturation can be defined as “the point at which no new information or themes are observed in the data” (Guest, Bunce, & Johnson, 2006, p. 59). Operationally, data saturation occurs when emerging information introduced into the data collection and analysis process generate little or insignificant alterations to the codebook (Guest, Bunce, & Johnson, 2006) thus, when significant thematic developments and coding is exhausted (Guest, Bunce, & Johnson, 2006). To Morse (as cited in Guest, Bunce, & Johnson, 2006) “at the crux of the discussion is how and when we define themes and how we eventually plan to present our data” (p. 77) which is solely at the discretion of the researcher vis-à-vis related factors such as resourcefulness as well as the relationship between the themes, data, and codes: in that codes are applied to data which in turn generate themes (Guest, Bunce, & Johnson, 2006). Yob and Brewer (n.d.) intended to generate themes that give practical meaning to the concept of positive social change mission in higher education settings. Although they did not explicitly indulge the reader in their concept and practice of saturation, by implication, vis-à-vis the research questionnaire and iteration frequency regarding interviews and coding one can argue that the authors’ data, codes, and theme, were related and aligned with the research questions and ultimately the research purpose.
It is evident that the qualitative strategy of inquiry is emergent or evolving. Evidently, the requirement for categorization of purposeful sampling strategy and data saturation are inexhaustive and emergent(Patton, 2015). Per the study of Yob and Brewer (n.d.) one can tell that a sampling strategy may reflect elements of more than the defined purposeful sampling strategy current identified by Patton (2015) while ultimately, a good qualitative research sampling strategy must reflect the participant and site of the study (Ravitch & Carl, 2016) associated with good research purpose (Creswell, 2009) data generation, coding, and thematic development (Guest, Bunce, & Johnson, 2006).
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