In order to find out if your study is original, you need to check theses already completed. Often you may find a methodology or many references which are useful in conducting and writing up your own thesis.
Apart from searching the various links on this page, you may search individual university repositories which usually contain theses and dissertations. Quite often there is no full-text but you can use our Document Delivery/InterLibrary Loan Service to get a full-text copy if it is available. Often older theses are not available full-text but it may be possible to get an abstract at least.