In a previous article (The Purpose of the PhD Literature Review), I introduced the concept of the literature review, which is a required part of every PhD even if it is not presented as a self-contained chapter. The starting point must be to identify and retrieve the resources necessary for your review. In this article I will set out one possible approach to completing that task.
The search for suitable material must be systematic. This will reduce the risk of missing an important publication and will reinforce the notion that sources were rationally and intentionally selected. The particular system I will describe is a good basic strategy, but you should still adapt it to suit the context of your research and your own needs.
Start with a review article or textbook chapter. From this you should be able to identify keywords to use for the formal search and it is also likely to reference major publications. Follow this up with a general internet search. Personally I use Google, Google Scholar, and Google Books, which can return some very useful resources and are easy to work with as you can use both keywords and natural language phrases. There is an increasing amount of academic material freely available, but be careful when using something that has not been published in a peer reviewed journal. Many examiners will see it as lazy if you are over reliant on such internet material.
The central part of your strategy should be to use a structured keyword search of the electronic databases that cover your subject area (e.g. Medline for medical sciences). This database search should be supported by a manual or online search of recent issues of the leading journals for current and advance access articles that have not yet been included in the databases. If you follow this system then you will be unlikely to miss any key publication, but if you need advice or support, the PhD Consultancy has experts who can meet your needs.