Types of Research

Longitudinal research is a research design in which the same people, cases, records, groups, or settings are studied more than once across a defined period of time. Instead of taking one snapshot, the researcher follows a process as it develops. This makes longitudinal research especially useful when the research question is about change, stability, sequence, […]

Cross-sectional research is a research design that studies people, groups, records, cases, or other units at one point in time. Instead of following the same units across months or years, the researcher collects data during a defined period and uses those data to describe conditions, compare groups, or examine associations between variables. This article explains

Comparative research is a research design in which researchers study two or more cases, groups, contexts, periods, policies, texts, or datasets side by side. The purpose is not simply to describe each case separately. The purpose is to understand how they are similar, how they differ, and what those similarities or differences suggest about the

Survey research is a research design that collects information from a defined group of people by asking them the same or comparable questions. The answers may describe opinions, behaviours, experiences, knowledge, needs, conditions, or background characteristics. Because the same instrument is used across many respondents, survey research can show patterns that are difficult to see

Case study research is a research design that studies one case, or a small number of cases, in depth and in context. The case may be a person, classroom, school, organisation, programme, event, community, policy, project, document set, or process. Instead of separating the case from its setting, the researcher treats the setting as part

Non-experimental research is a research design in which the researcher studies variables, groups, events, or records without manipulating an independent variable or assigning participants to treatment conditions. Instead of creating an intervention, the researcher observes what already exists, measures patterns carefully, and interprets the evidence within the limits of the design. This article explains what

Quasi-experimental research is a research design used to study the effect of an intervention, treatment, programme, policy, or exposure when participants cannot be randomly assigned to groups. It resembles experimental research because the researcher is interested in cause and effect, but it does not have the same level of control that a true experiment usually

Experimental research is a research design in which the researcher deliberately changes one or more conditions and observes the effect on an outcome. It is used when a study needs more than description or association. Instead of only asking whether two variables appear together, experimental research asks whether a controlled change in one variable produces

Theoretical research is a type of research that develops knowledge through concepts, models, arguments, and existing literature rather than through the collection of new observational or experimental data. It is used when a researcher wants to clarify an idea, build a theory, compare explanations, refine assumptions, or create a framework that later studies can use.

Empirical research is research based on evidence that can be observed, measured, recorded, or otherwise examined through systematic data collection. Instead of relying only on abstract reasoning or existing theory, empirical research asks a question about the world and then uses evidence to support, refine, or challenge an answer. This article explains what empirical research