Quantitative vs. Qualitative Research

Researchers frequently use qualitative and quantitative research methods to collect effective data for solving their research problem. There are advantages and disadvantages involved in quantitative and qualitative research.

Quantitative Research

Quantitative research is the systematic investigation of quantitative properties and phenomena and their interrelationships. Quantitative research uses numerical data based on the assumption that the numbers will describe a single reality.

Statistics are often applied to find relationships between variables.

The objective of quantitative research is to develop and employ mathematical models, theories, and/or hypotheses of natural phenomena.

The process of measurement is central to quantitative research because it provides the fundamental connection between empirical observation and the mathematical expression of quantitative relationships.

Quantitative research is widely used in both the natural sciences and social sciences, from physics and biology to sociology and journalism.

Quantitative research largely depends on two methods of data collection, viz., questionnaire method and experimental method.

Qualitative Research

In contrast to quantitative research, qualitative research is a field of inquiry that is employed to explore and understand people’s beliefs, experiences, attitudes, behaviors, and interactions.

Qualitative research uses descriptive data, e.g., a patient’s description of his/her lipid profile (high, low, or normal) rather than its measures.

Qualitative research is a generic term for investigative methodologies described as ethnographic, naturalistic, anthropological, field, or participant observer research.

It emphasizes the importance of looking at variables in the natural setting in which they are found. Interaction between variables is important.

Detailed data are gathered through open-ended questions that provide direct quotations. The interviewer is integral to the investigation (Jacob, 1988).

This differs from quantitative research, which attempts to gather data by objective methods to provide information about relations, comparisons, and predictions and attempts to remove the investigator from the investigation (Smith, 1983).

Qualitative researchers aim to gather an in-depth understanding of human behavior and the reasons that govern this behavior.

It investigates the why and how of decision-making, not just what, where, and when. Hence, the need is for smaller but focused samples rather than large random samples.

A qualitative researcher typically relies on four methods of data collection:

1. Participant observations.
2. Direct observations.
3. In-depth interviews.
4. Document and materials analysis, such as journals, diaries, images, or blogs.

Some distinctive qualitative research methods are focus group discussion (FGD) and key informant interviews (KII).

The focus group technique involves a moderator facilitating a small group discussion between selected individuals on a particular topic. This method is particularly popular in market research and testing new initiatives with users/workers.

In social sciences, the most frequently used qualitative research approaches include, among others, the following:

Ethnographic research

This is a type of research used for investigating cultures by collecting and describing data that is intended to help in the development of a theory.

Ethical inquiry

This refers to an analysis of ethical problems. It includes the study of ethics as related to obligation, rights, duty, choice, etc.

Foundational research

Such research examines the foundations for a science, analyzes the beliefs, and develops ways to specify how a knowledge base should change in light of new information.

Historical research

This research allows one to discuss past, present and future events in the context of the present condition and allows one to reflect and answer such questions as where we have come from, where we are, who we are, where we are, where we are going, etc.

Grounded theory

This is an inductive type of research based on ‘grounded’ observations or data from which it was developed; it uses a variety of data sources, including quantitative data, review of records, interviews, observation, and surveys.

Phenomenology

It describes the ‘subjective reality’ of an event, as the study population prescribes; it is the study of a phenomenon.

Philosophical research

Such research is conducted by field experts within the boundaries of a specific field of study or profession, the best-qualified individual in any field of study to use an intellectual analysis, clarify definitions, identify ethics, or make a value judgment concerning an individual issue in their field of study.

What are the primary methods of data collection in qualitative research?

Qualitative research typically relies on participant observations, direct observations, in-depth interviews, and document and materials analysis. Some distinctive methods include focus group discussions (FGD) and key informant interviews (KII).

What are the two main types of sampling methods?

The two main types of sampling methods are probability sampling and non-probability sampling. Probability sampling ensures every unit has a known nonzero probability of selection, while non-probability sampling is based on the researcher’s discretion.

What are the four basic research designs a researcher can use?

The four basic research designs are survey, experiment, secondary data study, and observational study.

How is sampling significant in the research process?

Sampling involves selecting a relatively small number of items or portions (a sample) from a universe (population) to make inferences about the entire population. It contrasts with a census, where every member of the population is included.

How does the purpose of qualitative research differ from that of quantitative research?

Qualitative research aims to gather an in-depth understanding of human behavior and the reasons governing it, exploring the “why” and “how” of decision-making. Quantitative research, on the other hand, focuses on testing hypotheses and is more concerned with “what,” “where,” and “when.”

Differences Between Qualitative and Quantitative Research

What is the main difference between qualitative and quantitative research?

Qualitative research seeks to understand and interpret human experiences, focusing on the entirety of a phenomenon and using narrative information. In contrast, quantitative research focuses on specific concepts, uses structured procedures and formal instruments to collect numerical data, and emphasizes objectivity.

How does data analysis in qualitative research differ from that in quantitative research?

Data analysis in qualitative research focuses on language, signs, and meanings, analyzing narrative information holistically and contextually. In contrast, quantitative research uses statistical techniques to interpret numerical data, focusing on relations, comparisons, and predictions.

The following points are important to differentiate qualitative research from quantitative research and for an understanding of the advantages of one over the other;

1. In qualitative research, cases are selected purposefully, according to whether or not they typify certain characteristics or contextual locations. This contrasts with quantitative research, where many cases representing the population of interest are randomly selected.
2. Qualitative research is usually done through unstructured or semi-structured techniques, e.g., individual in-depth interviews or group discussions. In contrast, quantitative research follows structured interviews such as questionnaires or telephone interviews.
3. In qualitative research, there remains little scope to correlate variables to determine causality within a study framework. In contrast, researchers have ample opportunities in qualitative research to correlate dependent and independent variables to determine causality.
4. Data analysis in qualitative research is usually non-statistical. In contrast, quantitative research heavily depends on statistical analysis followed by statistical tools and techniques for interpreting the results and drawing valid conclusions.
5. In qualitative research, findings are not conclusive and cannot be used to generalize the population of interest. In quantitative research, findings are conclusive and can be used to recommend a final course of action.
6. In qualitative research, the researcher’s role receives greater critical attention. This is because, in qualitative research, the possibility of the researcher taking a ‘neutral’ role is seen as more problematic in practical and/or philosophical terms.
7. While qualitative data analysis can take various forms, it differs from quantitative analysis in its focus on language, signs, and meanings. In addition, qualitative research approaches its analysis holistically and contextually rather than being reductionistic and isolationistic.
8. Qualitative research methods are used to explore (i.e., hypothesis generation) or explain puzzling quantitative results. Quantitative research methods, by contrast, are more focused and are used to test the hypothesis.
9. Qualitative research is often used for policy and program evaluation research since it can answer certain important questions more efficiently and effectively than quantitative approaches. This is particularly the case for understanding how and why certain outcomes were achieved (not just what was achieved) but also for answering important questions about relevance, unintended effects, and impact of the programs such as;
   • Were the expectations reasonable?
   • Did processes operate as expected?
   • Were the key persons able to carry out their duties?
   • Did the program cause any unintended effects?
10. Qualitative research approaches have the advantages of allowing for more diversity in response as well as the capacity to adapt to new developments or issues during the research process.
11. While qualitative research can be expensive and time-consuming to conduct, many fields of research employ qualitative techniques that have been specifically developed to provide more succinct, cost­efficient, and timely results. Rapid Rural Appraisal (RRA) is one formalized example of these adaptations, but many others exist.

We now summarize below the difference between qualitative and quantitative research in tabular form: