Research design has many definitions, but no single definition imparts the full range of essential aspects. Few of the definitions of research design are:
- Research design constitutes the blueprint for the collection of data, measurement of data and analysis of data.
- Research design aids the researcher in the allocation of limited resources by posing crucial choices in research methodology.
- The research design is the plan and structure of investigation so conceived as to obtain answers to research questions. The plan is the overall scheme or program of the research. It includes an outline of what the investigator will do from writing hypotheses and their operational implications to the final analysis of data.
- Research design expresses both the structure of the research problem – the framework, organization, a configuration of the relationships among variables of a study – and the plan of investigation used empirical evidence on those relationships.
These definitions differ in detail, but together they give the essentials of research design:
- An activity and time-based plan.
- A plan always based on the research question.
- A guide for selecting sources and types of information.
- A framework for specifying the relationships among the study’s variables.
- A procedural outline for every research activity.
Research design provides the glue that holds the research project together. A design is used to structure the research, to show how all of the major parts of the research project, the samples or groups, measures, treatments or programs and methods of assignment, work together to try to address the central research questions. A research design is the arrangement of conditions for collections and analysis of data in a manner that aims to give relevance to the research purpose with economy in procedure. In fact, research design is the conceptual structure within which research is conducted; it constitutes the blueprint for collection, measurement and analysis of data.
Some different design approaches exist, but, unfortunately, no simple classification system defines all the variations that may be considered. They may be exploratory study, formal study, monitoring, communication study, experimental, ex-post facto, descriptive, casual, cross-sectional, longitudinal, case study, field setting, laboratory research, simulation, actual routine, modified routine, etc.