Q: How long should the rationale of the study be?
There is no prescribed length as such for the rationale (or justification) of the study. Plus, it depends on several factors.
- Research document: In a thesis/dissertation, you get more space compared with a journal article. So, your rationale in the former could be longer than that in the latter.
- Research question: Research into an absolutely new area may warrant a somewhat long/detailed justification, whereas research that aims to plug a gap in literature may not require a very long explanation.
- Background of study: At times, the background of the study may lead into or blend seamlessly into the rationale, as both in a way talk about the ‘why’ of the study.
You should let your research question and literature search guide you on the length. Having said that, you could go with a thumb rule of a para or so for the paper (adding a para or so if it’s a thesis/dissertation) and about three/four lines for the proposal. At times, the length in the proposal could be more because, after all, you need to convince your supervisor/senior/funder with a strong rationale. :-)
For tips on writing the actual rationale, you may refer to the following resources:
- How to write the rationale for research?
- Can you give an example of the "rationale of a study"?
- How to write the first paragraph in the rationale of research?
All the best for the rationale – and the entire study/paper!