Research design requires careful consideration of elements that define the scope and credibility of a study. Three elements—assumptions, limitations, and delimitations—establish boundaries and clarify the research context. These components guide how a study is conducted, interpreted, and generalized. This paper examines the definitions, roles, and implications of research assumptions, limitations, and delimitations, supported by scholarly references.
Research Assumptions
Assumptions are foundational premises accepted as true without direct evidence, forming the basis for research design and interpretation. They often stem from theoretical frameworks, prior studies, or practical constraints. For example, a researcher studying educational outcomes might assume that participants answer survey questions honestly. Such assumptions underpin methodological choices but remain unverified during the study.
Methodological assumptions relate to data collection and analysis. A quantitative study might assume that statistical tools accurately measure relationships between variables (Creswell & Creswell, 2018). Qualitative research may assume that participant interviews reflect genuine perspectives (Merriam & Tisdell, 2016). Theoretical assumptions involve beliefs about how concepts interact. A study grounded in social learning theory might assume that observational learning influences behavior (Bandura, 1977).
Other Examples of Assumptions in a Qualitative Study
A qualitative study exploring patient experiences with chronic illness management may operate under several assumptions. The researcher might assume that participants provide truthful accounts of their experiences during interviews, even though subjective recall or social desirability biases could influence responses (Merriam & Tisdell, 2016). Another assumption could involve the study’s theoretical framework; for instance, the researcher might assume that social constructivism adequately explains how individuals interpret their health journeys, prioritizing personal meaning-making over biological factors (Creswell & Poth, 2018). Methodologically, the study might assume that thematic analysis accurately captures patterns in participant narratives, even if alternative analytical approaches could yield different interpretations (Braun & Clarke, 2006). These assumptions shape the study’s design but remain untested during data collection.
Unacknowledged assumptions risk undermining validity. For instance, assuming homogeneity in a population without evidence may introduce bias. Researchers must document assumptions to clarify their influence on findings (Simon & Goes, 2013).
Research Limitations
Limitations are factors outside a researcher’s control that constrain the study’s scope, accuracy, or generalizability. These weaknesses arise from methodological choices, resource constraints, or unforeseen challenges. Identifying limitations demonstrates transparency and helps contextualize results.
Common limitations include sample size, measurement tools, and time constraints. A small sample size may limit statistical power in quantitative studies (Faber & Fonseca, 2014). In qualitative research, reliance on self-reported data may introduce recall bias (Creswell & Poth, 2018). Longitudinal studies often face attrition, where participants drop out over time, affecting data consistency (Caruana et al., 2015).
Limitations also stem from theoretical frameworks. A study using a single theory may overlook alternative explanations for phenomena. For example, research focusing on cognitive factors in decision-making might neglect socio-cultural influences (Kahneman, 2011). Acknowledging such limitations allows readers to assess the study’s reliability and consider areas for future research.
Other Examples of Limitations in a Qualitative Study
Limitations in a qualitative study on teacher burnout might include a small sample size of 15 participants from a single urban school district, which restricts the transferability of findings to other educational contexts (Creswell & Poth, 2018). The reliance on self-reported data through semi-structured interviews could introduce recall bias, as participants may unintentionally omit or misrepresent stressful experiences (Hammersley & Traianou, 2012). The researcher’s dual role as an interviewer and former educator might create subjectivity during data analysis, potentially influencing how themes are identified or prioritized (Merriam & Tisdell, 2016). Time constraints may also limit the depth of follow-up interviews, reducing opportunities to clarify ambiguous responses. Such limitations underscore the need for cautious interpretation of results.
Research Delimitations
Delimitations are boundaries intentionally set by the researcher to narrow a study’s scope. Unlike limitations, delimitations reflect conscious choices rather than external constraints. They define what a study includes or excludes, ensuring focus and feasibility.
Delimitations often address population, geography, or variables. A study on workplace productivity might delimit its sample to employees in a specific industry (Saunders et al., 2019). Geographic delimitations restrict research to a region, such as examining climate policies in Nordic countries (Jørgensen et al., 2020). Theoretical delimitations exclude certain variables; for example, a study on exercise habits might omit dietary factors (Biddle & Mutrie, 2008).
While delimitations enhance manageability, they also affect generalizability. A study limited to urban populations may not apply to rural settings. Researchers must justify delimitations to clarify their rationale and impact (Marshall & Rossman, 2016).
Interplay Between Assumptions, Limitations, and Delimitations
These elements interact to shape research outcomes. Assumptions influence data interpretation, while delimitations narrow the study’s focus. Limitations highlight potential weaknesses in the resulting conclusions. For example, a researcher assuming that survey respondents understand technical terms may face limitations if participants misinterpret questions. Delimiting the study to professionals in a field might mitigate this but reduce applicability to broader populations.
Transparent reporting of these components strengthens credibility. Readers can evaluate whether assumptions are reasonable, limitations are addressed, and delimitations are justified. This transparency also aids replication, as other researchers can test the study under different conditions (Open Science Collaboration, 2015).
Examples in Practice
A quantitative study on vaccine efficacy might assume that trial participants represent the general population. Limitations could include a short observation period, restricting insight into long-term effects. Delimitations might exclude immunocompromised individuals to control variables (Poland et al., 2021).
In qualitative research, a project exploring teacher burnout may assume that interview participants openly share experiences. Limitations might involve a single school district, reducing transferability. Delimitations could focus on public schools, excluding private institutions (Maslach & Leiter, 2016).
Ethical and Practical Considerations
Ethical research requires acknowledging assumptions, limitations, and delimitations to avoid overstating findings. For instance, a medical study with delimitations excluding elderly patients should not claim universal applicability. Similarly, assumptions about cultural homogeneity in a diverse sample may lead to biased interpretations (Hammersley & Traianou, 2012).
Practical challenges, such as funding or time, often shape delimitations. A researcher with limited resources might delimit data collection to one region. While necessary, such choices must be clearly stated to prevent misinterpretation (Robson & McCartan, 2016).
Why Include Assumptions, limitations, and delimitations in a study?
Assumptions, limitations, and delimitations collectively define a study’s framework. Assumptions provide foundational beliefs, limitations identify constraints, and delimitations set intentional boundaries. Explicitly addressing these elements enhances transparency, credibility, and reproducibility. Researchers must document them to contextualize findings and guide future inquiry. By systematically addressing these components, scholars contribute to a robust and ethically grounded body of knowledge.
References
Bandura, A. (1977). Social learning theory. Prentice Hall.
Biddle, S. J. H., & Mutrie, N. (2008). Psychology of physical activity: Determinants, well-being, and interventions (2nd ed.). Routledge.
Braun, V., & Clarke, V. (2006). Using thematic analysis in psychology. Qualitative Research in Psychology, 3(2), 77–101. https://doi.org/10.1191/1478088706qp063oa
Caruana, E. J., Roman, M., Hernández-Sánchez, J., & Solli, P. (2015). Longitudinal studies. Journal of Thoracic Disease, 7(11), E537–E540. https://doi.org/10.3978/j.issn.2072-1439.2015.10.63
Creswell, J. W., & Creswell, J. D. (2018). Research design: Qualitative, quantitative, and mixed methods approaches (5th ed.). Sage.
Creswell, J. W., & Poth, C. N. (2018). Qualitative inquiry and research design: Choosing among five approaches (4th ed.). Sage.
Faber, J., & Fonseca, L. M. (2014). How sample size influences research outcomes. Dental Press Journal of Orthodontics, 19(4), 27–29. https://doi.org/10.1590/2176-9451.19.4.027-029.ebo
Hammersley, M., & Traianou, A. (2012). Ethics in qualitative research: Controversies and contexts. Sage.
Jørgensen, H. K., et al. (2020). Climate policy in the Nordic region: A comparative analysis. Environmental Politics, 29(3), 487–506. https://doi.org/10.1080/09644016.2019.1684732
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.
Marshall, C., & Rossman, G. B. (2016). Designing qualitative research (6th ed.). Sage.
Maslach, C., & Leiter, M. P. (2016). Understanding the burnout experience: Recent research and its implications for psychiatry. World Psychiatry, 15(2), 103–111. https://doi.org/10.1002/wps.20311
Merriam, S. B., & Tisdell, E. J. (2016). Qualitative research: A guide to design and implementation (4th ed.). Jossey-Bass.
Open Science Collaboration. (2015). Estimating the reproducibility of psychological science. Science, 349(6251), aac4716. https://doi.org/10.1126/science.aac4716
Poland, G. A., Ovsyannikova, I. G., & Kennedy, R. B. (2021). SARS-CoV-2 vaccine development: Current status. Mayo Clinic Proceedings, 96(6), 1562–1571. https://doi.org/10.1016/j.mayocp.2021.04.004
Robson, C., & McCartan, K. (2016). Real world research (4th ed.). Wiley.
Saunders, M. N. K., Lewis, P., & Thornhill, A. (2019). Research methods for business students (8th ed.). Pearson.
Simon, M. K., & Goes, J. (2013). Dissertation and scholarly research: Recipes for success. Dissertation Success.