When writing a thesis, there are many essential elements to develop in order to give the reader a clear understanding of the research. Two of these components are the scope and the limitations.
In a thesis, the scope defines exactly what will be covered in a study, while the limitations are the constraining aspects that may have influenced or affected the research. For example, if the study covers the native population of a particular region, that specific population is the scope. If the researcher has a bias due to inclusion in this population, then this is a limitation.
The scope is very important to the overall quality of a thesis. It should be developed at the beginning of the study because it will need to be referenced to guide the research along the way. Developing a strong scope is a matter of striking a balance. The researcher will need to hone in on a very specific topic, as studying one question in depth is generally more useful than surface-level coverage of a broader subject. Simultaneously, a topic cannot be so narrow as to leave little to be researched or answered. In addition, the scope should address a question that has not yet been answered in depth, yet is not so obscure as to leave the researcher with a complete lack of reference material with which to work.
Researchers can start developing a scope with a single overarching research question. Though a few additional subheadings may be desired, a one-question limit forces the research to stay focused. Question words such as "how," "why" and "which" are useful for a thesis, as they encourage a deeper, more critical thought process during research.
All studies are limited by various factors, and like the scope, limitations should also be considered early on. Any controllable limitations, such as a flaw in the research design, can then be adjusted or removed before finishing the thesis. Regardless, the completed research will have limitations, and these must be mentioned in the thesis. The researcher should approach it honestly and realistically, neither over- or understating the limitations.
Different types of study may be prone to certain types of limitations. The research methods must be carefully considered to avoid unnecessary limitations. For example, case studies are typically focused on one person or group, which may or may not be indicative of other similar scenarios. Most case studies will therefore naturally limit the researcher's ability to generalize without further research. Studies that require instrumentation for measurements are limited by the ability and quality of the instruments. Survey-based research can be limited by the participants' ability to answer the question precisely. In other words, the questions, available answers, or space available can limit or even change the participants' desired answers.
A solid limitations section in a thesis will directly state all of the potential limitations but will not stop there. It should also justify how research design decisions were made, as well as why certain limitations were deemed acceptable over others. Ideally, the researcher will provide suggestions on how the limitations of the current study might be avoided in future research.