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B. Qualitative versus quantitative approaches

Although it is meaningful to do qualitative research in itself, qualitative research is often defined by reference to quantitative research. Often it is assumed that because qualitative research does not seek to quantify or enumerate, it does not ‘measure’. Qualitative research generally deals with words or discourses rather than numbers, and measurement in qualitative research is usually concerned with taxonomies or classifications. “Qualitative research answers questions such as, ‘what is X, and how does X vary in different circumstances, and why’, rather than ‘how big is X or how many X’s are there?”(Pope, 2006, p3).

By emphasizing the differences the qualitative and quantitative approach are presented as opposites. However, qualitative and quantitative approaches are complementary and are often integrated in one and the same research project. For example in mixed methods research the strengths of quantitative and qualitative research are combined for the purpose of obtaining a richer and deeper understanding (Zang, 2012). Also qualitative data could be analyzed in a quantitative way by for example counting the occurrence of certain words.

Often health services researchers draw on multiple sources of data and multiple strategies of inquiry in order to explore the complex processes, structures and outcomes of health care. It is common that quantitative and qualitative methods answer different questions to provide a well-integrated picture of the situation under study(Patton, 1999). Especially in the field of health services research qualitative and quantitative methods are increasingly being used together in mixed method approaches. The ways QRMs could be used combined or not, are:

 Qualitative research only:

  • To know the variation in experiences related to health or illness.
  • To build typologies regarding health services use, patient attitudes, health beliefs, etc.
  • Qualitative preliminarly to quantitative:
  • To explore new area, new concepts, new behaviour, etc.(Pope, 1995) before to start with measurement.
  • To build quantitative data collection tools (questionnaires): using appropriate wording(Pope, 1995), variables to submit, to develop reliable and valid survey instruments(Sofaer, 1999), etc.
  • To pre-test survey instruments(Sofaer, 1999).
  • In supplement to quantitative work:
  • As a part of a triangulation process that consist in confronting results coming from several data sources(Pope, 1995).
  • To reach a different level of knowledge(Pope, 1995): “If we focus research only on what we already know how to quantify, indeed only on that which can ultimately be reliably quantified, we risk ignoring factors that are more significant in explaining important realities and relationships.” (Sofaer, 1999, p. 1102).
  • In complement to quantitative work by exploring complex phenomena or areas that are not reachable with quantitative approaches(Pope, 1995).
  • Sofaer(Sofaer, 1999) provides us the insight that in many cases, inquiry can move from being unstructured, largely qualitative in nature, to being structured and largely quantitative in nature. This is how she describes the continuum: “(…) there is uncertainty not only about answers, but about what the right questions might be; about how they should be framed to get meaningful answers; and about where and to whom questions should be addressed. As understanding increases, some of the right questions emerge, but uncertainty remains about whether all of the right questions have been identified. Further along, confidence grows that almost all of the important questions have been identified and perhaps framed in more specific terms, but uncertainty still exists about the range of possible answers to those questions. Eventually, a high level of certainty is reached about the range of almost all of the possible answers.” (p. 1103).
  • In sum, over time investigations related to a certain area, start with qualitative research to explore the field, find the right questions, prepare for more focused questions and discover theories and hypotheses. Next, quantitative research is in place to test hypotheses and finally, qualitative research can be used to deepen the findings or to search for explanations quantitative research techniques cannot provide.