There are various ways to start a search in search tools (databases, library catalogs, discovery systems, and search engines). One of the best-known methods is the called “snowballing”:
Snowballing
With snowballing, you start with a publication that you have already found for your topic.
Then you can look at the list of works cited or bibliography of the publication. Note that the publication should be as up-to-date and relevant as possible, as you can then use its list of works cited and bibliography to find the most important recent and older publications on the topic. The starting point for this search strategy can be works from a course reading list or suggestions from lecturers or other experts. Databases such as „Web of Science“ display the reference of its articles, with direct links to the cited literature.
Some databases such as „Web of Science“ and „Google Scholar“ also make it possible to search forward in time. This means that you can find out which publications have cited your source and thus access the most recent publications on your subject.
Another starting point for a snowballing search can also be the author of a given article, as they often publish numerous works on the same topic. In various academic databases as well as in Google Scholar, links are provided that lead to an overview of an author’s publications. Another option is ResearchGate: an academic networking site on which researchers can list their publications. ResearchGate allows you to conduct a keyword search. Researchers usually also have a profile page on the website of their institution or university, on which you can find their current projects and publications.
If in the process of reading and reviewing the literature the amount of new information is becoming increasingly smaller, the search can be aborted.
Other Strategies
- Trial and error
This method is suitable if you are dealing with a very recent topic. When searching by trial and error, you use keywords and work with Boolean operators and truncations. This allows for an associative and flexible search. At the beginning of the search, a keyword search is carried out across all fields of a catalog, discovery system, database or search engine. All relevant search fields are searched simultaneously: Author, title, keyword, abstract etc. This usually yields a very large number of results, which can then be scanned for the most important titles. The list of results can also be filtered according to certain criteria such as language, year(s) of publication, publication type, etc., so that a meaningful list of results remains at the end. This type of search is also used in catalogs, discovery systems and databases to find the relevant keywords. Relevant titles can be checked for their keywords. If suitable, the keywords can then be added to the search. - Divide your topic into subtopics
Divide your topic into subtopics and conduct a search on these one by one.
For example, for the topic „Media use by young people“, you can first conduct individual searches on the topics of media use, media consumption, television consumption, Internet use, computer games, chatting and so forth. In the next step, you can then link your search queries to obtain results at their thematic intersection. - Structured search with controlled vocabulary
In a conventional, structured search, you use the thesaurus of a database and search using subject headings. In this, search terms are found using indexes (of for example subject headings or authors). Thanks to a standardized and normalized vocabulary, relevant results are obtained in a controlled way and unsuitable results are avoided. This type of search is only possible in traditional library catalogs and academic databases. Newer search tools such as swisscovery or SpringerLink no longer offer a controlled vocabulary in a comprehensive way.
Marius Metzger from the Lucerne School of Social Work has written a brief guide to conducting systematic literature searches for students (in German): Systematisch Recherchieren – Eine Anleitung für Studierende