Before starting your search, you need to be clear about what sort of evidence you are looking for. To begin with, you need to have a clearly formulated question. Understanding the type of question you have, and knowing what the best study design is to answer that question, will help to determine where and how to search for evidence.
This following presentation uses a scenario to formulate a clinical question, and demonstrates the steps involved in building an effective search strategy.
As you have seen, there are many sources of evidence available to you, in a range of databases, publications and websites. Any search can retrieve several thousands of articles, so to perform an accurate search for relevant high quality evidence you need to be able to search specific aspects of your question and limit the number of search results to a manageable level.
However, when you are creating a search strategy it is a good idea to start with a wide or "sensitive" search. This will mean that you find a lot of papers initially that may not be relevant, but to narrow or limit the search too quickly could mean that you miss a vital piece of evidence relevant to your question.
The following presentation will take you through the process of building your search strategy and using a range of search techniques. It will also help you to filter your results by quality to ensure that you retrieve the best available evidence for your question.