The literature review is an overview of significant literature on a particular topic, which can either be self-contained, or form part of the introduction to your essay.The purpose of the literature review is to place your own question or topic for study within the context of previous and current research.
When developing a search strategy to find information on a particular topic it is useful to start with a clear and focused question. Then, identify the main ideas or concepts around that question or topic using PICO.
P for Population = this represents the patient or group of patients or population with their own particular characteristics, problem or condition under review
I for Intervention = this represents the intervention, treatment or exposure that is applicable to this group
C for Comparison = is there an alternative to the Intervention? Sometimes there may be no comparison.
O for Outcome = what outcome are you hoping to see? An improvement in function or reduction in severity of symptoms
Now you should be able to identify your keywords/synonyms and develop a strategy for searching the databases of your choice
Example
Question: Does hand washing among healthcare workers reduce hospital acquired infections?
P = hospital acquired infections
I = hand washing
C = none
O = reduced infection
Keywords: Hospital-acquired infection*, nosocomial infection*, cross infection*, hand washing, hand disinfection (* truncates word so that both singular and plural are included)
Search strategy: (Hospital acquired infection* OR cross infection* OR Nosocomial infection*) AND (hand washing or hand disinfection)
When focusing on a qualitative research question you may find it more useful to use PIE which stands for:
P - Patient/Population/Problem
I - Intervention/Issue
E - Evaluation/Effect (which measures or methods are you using to evaluate the outcome?)