Having created a basic protocol, you will need to develop it into an effective search strategy. In health sciences you can use the PICO format to develop your research question. You should identify the population (P) and the intervention (I), plus a comparator (C) and the outcomes (O) for your research, where relevant. If you are doing an intervention review then PICO may be suitable, but for other types of review, other frameworks or tools may be more appropriate. You can find more information about PICO at the Information Skills 3 section of the HYMS Skills Tutorials page.
It is very important to define clearly which kind of studies will be included in your review before starting the search.
Doing this will help you to establish clear exclusion and inclusion criteria for your review and allow you to save time and effort.
You should check that your review has not already been done or that there is one currently in progress (eg for health reviews check CDSR, DARE, PROSPERO -- see the links below).
It is advisable to add your final protocol to PROSPERO (if health-related) so you can cite it and others can be aware of your ongoing research (see the link below).