A well defined topic will ease your search for information. To focus your information search, it is often helpful to put your topic in the form of a question. Your research question may develop or change as you carry out preliminary research.
Start by considering the following factors to narrow your topic: Who, What, Where, and When.
Who could indicate the subjects of research nurse, a patient, or a family or allied health colleague.
What could be a disease, therapy, or a problem to address.
Where might include a physical setting (hospital, residence, community) or an anatomical location (heart, lower limbs).
When could denote a point in history (World War II), a time frame (in the last 10 years), or 'when' in the course of therapy (newly diagnosed, palliation).
Some examples include:
How do patients cope with diabetes? (who and what)
How has home care for seniors evolved over time? (who, what and when)
What can nurses do to effectively communicate in a busy clinical setting? (who,what, and where)
Which therapies should be administered to patients at home during the first months after a stroke? (who, what, when, and where)
An initial literature search for information using library and web resources will give you an idea of how your topic has been covered in the literature. Performing preliminary research may also allow you to refine your topic based on your interests or available research.