If you struggle to identify additional keywords for your search terms you could:
The intervention or exposure is usually the easiest to define. If you get too many results you could consider redoing this search string as a title or abstract search. This will limit and focus the search results. Alternatively if you are not getting enough results, try searching just for the intervention or exposure.
You may not need to search for each part of the PICO, PIO or PEO formula. If you are not getting enough results, consider leaving one part out of your search. For example, outcomes can be difficult to define (e.g. improving patient care) and may make your results too specific.
If you are comparing an intervention to standard care or no intervention – you may need to do more than one search. One which includes the intervention and one which does not. Simply searching for terms like ‘standard care’ or ‘no intervention’ may not be effective on their own.
It does not matter if your database search does not follow the same order as your PICO, PIO or PEO statements.
Some terms may require more than one search string e.g. if your population is dementia patients in an acute setting. You will need to search for dementia and acute setting separately, before combining them together e.g.:
Search 1: Acute care OR acute setting OR hospital
Search 2: Dementia OR Alzheimer OR cognitive impairment OR memory loss
Search 3: Search 1 AND Search 2