A research question is cultivated through researchers' efforts to know the existing literature, their clinical expertise and interests, their collaboration with peers, and their intrinsic motivation towards scientific discovery and innovation. Answerable, appropriate, meaningful, and purposeful research questions make valid and needed contributions to the literature.
Deductive reasoning should be used when formulating a research question. Oftentimes, researchers will want to answer EVERY possible question and collect data on EVERY single variable that they can in hopes of finding SOMETHING SIGNIFICANT. This is not the way that REAL science works. A focused and refined research question is the basis for constructing and executing research. This does not mean that researchers cannot ask secondary, tertiary, and ancillary research questions as demographic, clinical, and confounding variables are yielded from literature reviews! Of course, these are important questions to ask and often lead to great discoveries! (Example: Viagra) However, having ONE research question that serves as the foundation for a study is extremely important and should not be overlooked!
Many novice researchers will plan an entire study around a type of research design or a statistic that they read in an article. REMEMBER, research designs and statistical tests are chosen to answer researcher questions, NOT the inverse.
All of this being said, there are two existing frameworks that greatly assist in formulating (FINER) and refining (PICO) research questions. FINER stands for feasible, interesting, novel, interesting, and relevant. PICO stands for population, intervention, comparator, and outcome.