The PICOT question is made in a formula (format) of creating re-searchable and answerable inquiry.
Example of PICOT question; Patients aging 55 years and above (P), how is the application of an influenza vaccine (I) compare not obtaining related vaccine influence the possible pneumonia contract (O) in the flu season (T)?
Levels of evidence; evidence levels, pyramid normally give a way to see the quality of evidence plus the available evidence. Example, systematic reviews are at top of pyramid. Evidence increases as quality of the evidence decreases downwards.
Databases
1. Academic Search Complete. It is a multidisciplinary database that usually contain reviewed peer journals, the conference papers, the newspapers, the magazines plus many more