PICO is a tool that will assist you to fully analyse your query and form a well constructed, focused and answerable question.
PICO is especially useful for therapeutic questions but can be adapted to any type of question.
PICO for clinical questions
PICo for qualitative questions
COPES (social work) - Client-Oriented, Practical, Evidence Search
Client type and problem, what you might do, alternate course of action, what you want to accomplish
PECODR (clinical) - Patient, Exposure, Comparison, Outcome, Duration, Results
Useful for case control studies and cohort studies. Duration (length of the follow up period), results (Number Needed to Treat or similar)
PESICO (rehabilitation) - Patient, Environment, Stakeholders, Intervention, Comparison, Outcome
PIPOH (guidelines) - Population, Interventions, Professionals/Patients, Outcome, Health Care Setting