Table of Contents  
Year : 2012  |  Volume : 5  |  Issue : 2  |  Page : 93-96  

Application of qualitative methods to health and biomedical research

University of Ottawa, Ottawa, Ontario, Canada

Date of Web Publication10-Nov-2012

Correspondence Address:
Carol Vlassoff
6-200 Cathcart St., Ottawa, ON, K1N5B9
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0975-2870.103321

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How to cite this article:
Vlassoff C. Application of qualitative methods to health and biomedical research. Med J DY Patil Univ 2012;5:93-6

How to cite this URL:
Vlassoff C. Application of qualitative methods to health and biomedical research. Med J DY Patil Univ [serial online] 2012 [cited 2023 Dec 5];5:93-6. Available from:

In undertaking a research project, the choice of methodology depends upon a number of factors, including the nature of data to be collected to answer the research question, the unit of analysis and the assumptions underlying the approach. The choice of qualitative or quantitative methods is central to this process, and both may be required to respond adequately to our question.

It is perhaps easiest to understand qualitative research by contrasting it with quantitative research. Both quantitative and qualitative methods are used in social science research and in the application of the social sciences to biomedical and public health sciences. In brief, quantitative methods use a deductive approach, beginning with a hypothesis that can be measured through defining and quantifying the study subject matter. The purpose of the exercise is to allow prediction of future behaviour or interactions between and among variables. The methods are structured, using questions and predefined codes, and as such are replicable by other researchers. The questionnaires should be pre-tested in a setting or among subjects other than those selected for the research itself. Quantitative methods may be conducted in a formal interview setting, such as an office or classroom, or in an informal setting, such as the respondent's home.

Qualitative research uses an inductive approach, seeking to understand and illuminate a topic or subject of study. Rather than beginning with a specific hypothesis as to what is expected or predicted, qualitative research questions are more open-ended, exploring a variety of possible aspects of the issue of interest. It therefore requires an exploratory perspective that is both broad and complex. It delves beyond the appearance of the subject matter to deeper meanings and contexts. Its results are descriptive, not quantifiable, and often raise questions for further research. While the research process, in terms of the questions asked, may be replicated by different researchers, the course of questioning will be variable, depending upon the paths followed in the application of the methods. Most qualitative methods, such as observation or in-depth interviews, take place in natural environments.

It is important to note that, in most situations, qualitative methods alone are insufficient to definitively answer a research question, especially in public health and biomedical sciences. However, they play a useful role as a complementary method in several ways. This can be seen by envisioning a doctor-patient encounter in a routine consultation. The doctor begins by asking a number of general questions, such as how has the client been feeling, what symptoms has he/she been experiencing, what kinds of activities has he/she been involved in, etc. Such exploration helps the doctor identify the probable cause of the complaint and know where to focus his/her physical examination of the patient.

A similar type of investigation may be needed in research, where the first stage may involve qualitative exploration before quantitative investigation or survey. For example, the first stage of a malaria research project, such as field trials of bed-nets, insecticides or pharmaceuticals, may benefit from a study of the way malaria is perceived by the local population. Do people understand that malaria is transmitted by the mosquito, or do they attribute it to other causes such as exposure to rain, cold or certain foods? To answer this question, a stage of general observation of the behaviour of the local people and discussions with a range of community members with different socioeconomic characteristics should be sufficient to guide the intervention trials. Thus, qualitative methods can help explain how individuals and communities understand health and disease, illuminate interactions relevant to a public health issue, and offer suggestions as to issues that need to be addressed before and during the course of the research.

Another useful contribution of qualitative exploration is generation of hypotheses for further investigation. An example from qualitative research on perceptions of malaria in rural Tanzania illustrates this point. Both cerebral and vivax malaria were prevalent in the community, and people understood a great deal about the modes of transmission of the infection and prevention methods. However, a surprising finding emerged: While people sought medical attention for Plasmodium vivax malaria, they did not frequently do so for the more severe Plasmodium falciparum type. The explanation was that the latter was thought to be caused by visitations of evil spirits because of its dramatic manifestation, convulsions. Thus, when people witnessed convulsions, they immediately sought help from a traditional healer who they believed could pacify the source of the problem. This finding led to the conclusion that general health education messages for malaria prevention were insufficient to address the community's understanding of the disease and that different messages should be developed for the different kinds of malaria and its manifestations. [1]

Qualitative research, when conducted along with quantitative surveys, can help explain unexpected findings, which could not be understood by survey methods alone. For example, 0in my research in a village in rural Maharashtra, I found that mortality was higher during the rainy season than at other times, based on quantitative information reported in village vital statistics records. This could not be attributed to lack of access to health facilities during the monsoon because a primary health centre was located close to the village and functioned year round. However, an interesting behavioural change occurred during this time. Whereas the villagers obtained their drinking water from wells during the dry season, they chose to drink from the river during the monsoon because they preferred its taste. Naturally, the river was exceptionally polluted during this period due to an excess of debris carried from upstream settlements. This understanding was possible only because I lived in the community for extensive periods of time, combining both survey and qualitative approaches. [2]

Just as a medical doctor relies upon training, experience, trial and error in diagnosing a client's condition, qualitative research requires social science training and hands-on experience in the field. Just as the doctor learns to guide his/her questions towards the desired issues of interest, the qualitative investigator moves from general questions to a focus on subjects of greatest relevance to the study. Thus, application of qualitative approaches, like quantitative approaches, requires training and experience. Several different methods, each with their own design and degree of rigour, are used in qualitative research. [1] These include observation, key informant interviews, in-depth interviews, case studies, focus group discussions (FGDs) and semi-structured questionnaires. They may be used together, or along with quantitative approaches in a research project, in a methodology called "triangulation", further discussed below.

Observation is fundamental to good research, whether qualitative or quantitative. It is used in several forms, from the invisible observer to the fully disclosed observer living and participating in the daily life of a community or society. Invisible observation has been practiced in some settings, such as when the researcher interested in studying the doctor-patient relationship acts as a "mystery client" and does not disclose his or her true identity to the doctor. In general, this approach is not recommended for ethical reasons. The more transparent observer informs the research subjects about his/her objective and then observes and records certain characteristics of interest, such as hygiene practices or diarrhoeal episodes. Another example is the participant observer who lives for a period of time in the study area and experiences a situation along with the study subjects. For example, a researcher may live on the street with homeless people in order to experience this lifestyle first-hand and to have access to the population for observation and questioning. In the case of participant observation, some of the data gathered will be structured according to the interviewer's needs and preferences, such as in daily notes or checklists.

Key informant interviews are unstructured or semi-structured interviews that seek to elicit general information about the setting, socio-economic and political context, local activities or health problems in the research area. They are generally held as informal, open-ended discussions between the interviewer and the informant. Examples of key informants are many, such as a village leader, a member of a political party, a business leader, a representative of a women's self-help group or a primary healthcare provider. An interview with one key informant can have a snowball effect, as the interviewee may suggest other people who can give additional insights about the research topic. Obtaining such suggestions might even be one of the motives for the first interview, as the researchers are unlikely to have in-depth knowledge of the study context. In the case of a semi-structured interview, the investigator has a list of questions to guide the discussion (e.g. "Is there a primary healthcare centre here? How far away is it? How many private doctors are available?"). In the unstructured interview, the purpose is more general and exploratory (e.g. "Tell me about the health services in this area. Where do people go? Are there private doctors? Generally, are people satisfied with the services?").

In-depth interviews are one-on-one unstructured or semi-structured interviews that seek to elicit a respondent's personal opinions and experiences. They are especially useful for exploring sensitive issues such as stigmatized diseases (HIV/AIDS, leprosy) and for discussions with respondents unaccustomed to more formal interviews (rural women, widows, deserted women). As with key informant interviews, unstructured in-depth interviews may be used to become familiar with the situation of respondents having the characteristic of interest (e.g. a disease or marital situation) and the problems they face. The semi-structured in-depth interview follows a list of open-ended questions, which are used to guide the discussion. They are referred to as "open-ended" because they do not try to restrict the respondents' answers to certain pre-coded responses, and because the answer to one question may raise other relevant issues not previously considered. For example, when asked about stigma from the community, an HIV-positive man may reply that the greatest stigma was encountered in his own family. A number of questions would then logically follow on this topic (even though it was not included in the original question guide) because these insights are key to developing future interventions.

Case studies focus on individual cases, which can be simple (a single unit such as a child) or complex (a family or community). Here the focus is on understanding the peculiarities of a specific case rather than in generalizing from one to many. A case study may be derived from of a series of in-depth interviews or observations or both. For example, case studies may focus on individuals with a health problem such as leprosy or AIDS. The findings of several such case studies may lead to the generation of hypotheses, which can be further tested through quantitative research.

Focus groups and group discussions are also included in qualitative research methods, although they are conducted in a more formal, prearranged setting. [3] An FGD is distinguished from a general group discussion by selecting individuals with specific characteristics as opposed to a group of individuals in a natural setting where people with a variety of characteristics are included. For instance, if the research interest is in health problems of migrant labourers, an FGD may be organized with migrant labourers, excluding other types of workers. The FGD generally reveals commonly held opinions, attitudes and perceptions, and may provide new insights such as common vocabularies used by group members. The FGD is guided by a trained moderator with observational and interpersonal skills who asks questions in a structured way. A tape recorder is used, and participants must agree to have their answers recorded. The moderator is assisted by a note-taker, who also observes and records interactions among group members such as body language. FGDs reveal what people are willing to say about the topic publicly and do not necessarily reveal their private thoughts or opinions. As such, a good rule of thumb for how many FGD sessions to hold is that they should continue until no new information of interest is being generated. The process usually involves 4-6 sessions.

Semi-structured questionnaires are designed to obtain both quantitative and qualitative information. They generally consist of questions with a number of possible answers that can be checked off and later coded, and spaces are provided after the questions for recording what people say about their answers. Several questions may also be completely open-ended, with spaces left for the answers, in which case the responses are not pre-coded by the researcher. Questions such as "Why do you say that?" or "Can you explain what you mean?" are examples of open-ended questions. Having both quantitative and qualitative answers on one questionnaire facilitates the linking of the two different types of data. Computer programmes are available to facilitate such linking and analysis. Rigorous training and supervision of interviewers is extremely important for administering semi-structured questionnaires: Interviewers need to exercise patience and take the time to probe for people's deeper explanations rather than skipping over these in the interest of time.

Having outlined the different qualitative methods available, it should be emphasized that these methods alone are insufficient to reach definitive conclusions about a subject or hypothesis. For example, qualitative methods are subjective, relying on the observations or insights of the researcher, and all too often conclusions can be derived from purely anecdotal information. It is tempting to emphasize the unusual or sensational case or finding, and to play down the more obvious results. For example, in a broad evaluation of a health programme, 20 professionals provided independent evaluations through in-depth interviews. The researcher reported that two responses pointed out deficiencies and derived recommendations from these, rather than commenting and building on the 18 positive responses. Another deficiency in relying on qualitative methods alone is that their findings are not generalizable, although they should point the way to a potential generalizable result. For these reasons, triangulation of research methods is highly recommended. Two examples of triangulation from my village study in India are provided below.

Triangulation is a methodology that combines different methods, such as analysis of secondary sources (documents, village records), observations and interviews, to provide historical, socioeconomic, political and cultural contexts, as well as different perspectives on the subject of study. It provides a way of understanding how different assumptions may affect findings or illuminate inconsistencies. For example, in examining the relationship between women's employment and indicators of empowerment in rural Maharashtra, I found that the usual positive relationship between these indicators (that employed women would be more empowered because they were earning) was not found. In fact, the majority of employed women were less socially and economically empowered than women who were not employed. Several other researchers had also commented on this surprising finding. However, through my daily experience of living in the village (qualitative information), the explanation was clear. The largest category of employed women was wage labourers who made minimum daily wages and who generally turned over their earnings to their husband or in-laws, or used it entirely for household expenses. Only those who were self-employed (only 5% of all respondents) scored high on the empowerment indicators.

Another example of the value of triangulation was a finding that 88% of married village women could name at least one method of HIV prevention, yet very few of them had discussed their own potential risks with their husbands. [4] In their qualitative responses, women said that they believed that marriage protected them from infection. From FGDs with young married women, it also became clear that the social pressure to have a first child was stronger than the fear of infection, even for those whose husbands could be considered at high risk (e.g. truckers, migrants to urban areas). Similarly, adult male participants interviewed in FGDs adamantly declared that they would never discuss HIV with their wives because it was "off limits" in respectable marital relationships. The idea that marriage somehow protected couples from infection would not likely have been gleaned from the questionnaire data alone.

Triangulation of quantitative and qualitative methods can be used for a wide variety of purposes to improve the quality of research, including to refine research tools; develop, implement and evaluate interventions; further explore or test the findings of one method; study different aspects of the same topics; explore complex phenomena from different perspectives; and confirm or cross-validate data. Data collection, analysis and, identification of patterns and trends should be interrelated and interactive processes, allowing the research team to draw out important themes, patterns and relationships during and after data collection, and to develop hypotheses for future research. In all research, it is important to keep ethical considerations in mind, [5] including the need for informed consent from the respondents, explanation of the purpose, possible risks and benefits of their participation, assurance of confidentiality and the data collection procedures to be used. They should also be informed of whom to contact with questions and concerns. In this way, the respondent and interviewer establish a common ground and understanding upon which to build a positive research endeavour.

  References Top

1.Kikwawila Study Group. WHO/TDR Workshop on Qualitative Research Methods: Report on the Fieldwork. UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), Geneva; 1995 (SER/TDR/RP/95.2). Available from: [Last accessed on 2012 Oct 24].  Back to cited text no. 1
2.Vlassoff C. The Significance of Cultural Tradition for Contraceptive Change: A Study of Rural Indian Women. PhD Thesis. University of Poona, Poona; 1978.  Back to cited text no. 2
3.Dawson S, Manderson L, Tallo VL. A Manual for the Use of Focus Groups. Special Programme for Research and Training in Tropical Diseases (TDR), Geneva: World Health Organization; 1993.  Back to cited text no. 3
4.Vlassoff C, Weiss M, Rao S, Ali F, Prentice T. HIV stigma in rural and tribal communities of Maharashtra, India. J Health Popul Nutr 2012: (in press).  Back to cited text no. 4
5.Diener E, Cranall R. Ethics in Social and Behavioral Research. Oxford: University of Chicago Press; 1978. p. 266.  Back to cited text no. 5


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