Read the tekst in the box 'Search fields'.
In PubMed, go to 'Advanced', and search for articles in Nederlands Tijdschrift voor Geneeskunde (field: 'Journal') and with title/abstract word ‘Alzheimer’.
How many articles do you find?
(Click on the question to view the answer)
Read the text in de box 'Truncation and quotation marks' .
Suppose you are looking for literature on Neoplasms. In the Search Builder, change 'all field' to 'Title/Abstract' and try out the word variants, and always click on 'Show Index'.
What would be the best place to truncate?
(Click on the question to view the answer)
Read the text in the text box 'Combining search terms'.
The Sydney University Library has developed an online game to practise using brackets and Boolean operators. You will find the game here. (Note: allow the use of Flash Player!)
Read the text in the text box 'History and Search Details'.
With the help of 'History and Search Details' perform a seach in PubMed on the side effects (side effects or adverse effects) of vaccination (vaccination) against Swine Flu(swine flu or H1N1). Think carefully if you have to combine the separate parts with AND or OR.
How many results do you get? Are they relevant?
(click on the question to view the answer)
The default search in PubMed is both on the literally entered search terms in all fields, and the MeSH terms. You can edit the default search of PubMed by indicating the search fields yourself. Some options are: author name [au], journal title [ta] and title/abstract [tiab]. Tiab searching also includes searching for author keywords!
Behind the search term you can put the fieldname between square brackets yourself. To this end you can also use the 'PubMed's Advanced Search Builder' under ‘Advanced’.
Using the 'Builder' you can indicate for each search term in what field(s) must be searched. Default setting is 'All Fields', but you can change this yourself in a preferred field.
To build a search, you can enter a search term in each line of the 'Builder' (and select in what field the term must be searched). The entered search terms appears automatically in the search line at the top of the screen. You can click on to add this part to the query box.
For each new search term you indicate how you want them combined with the previously added search terms: with AND, OR or NOT (for more explanation see the box 'Combining search terms' below.)
Finally, you click on 'Search' or 'Add to history' to perform the search. If you select 'Search' you will go to the screen with search results. If you select 'Add to history" you will remain in the 'Advanced search' screen where you can immediately perform a new search or combine searches (more on this subject in the box History and Search Details).
To find words with different endings or alternative spellings you can use the truncation symbol: an asterisk (*). In that case PubMed searches on all words and word combinations starting with the letters in question. For instance: obes* searches both on the word 'obese' as on the words 'obesitas', 'obesity' and all other words and word combinations starting with 'obes'.
Note 1: In contrast to the legacy version of PubMed you can (but don't have to) use truncation and quotes simultaneously
Note 2: You only can put an asterisk at the end of a phrase or word. Don't use h*ematology for instance, to find British and American spellings!
In PubMed you can combine search terms with the help of the so-called Boolean operators OR, AND, and NOT. With OR, PubMed searches for results in which one or both search terms occur (fig. 1 below). If you combine two search terms with AND, PubMed will only search for results in which both search terms occur (fig.2). NOT produces all results in which the first term occurs, but the second does not (fig.3).
If you want to combine more than two search terms we recommend using brackets. Without brackets PubMed carries out the commands OR, AND and NOT in the order in which they are entered. This may give unwanted results!!
Suppose you are looking for articles about vaccination against swine flue. If you set up your search as follows:
vaccination AND swine flu OR H1N1
You will find articles in which the words 'vaccination' and 'swine flu' both occur, as well as articles in which the term 'H1N1' occurs (but which do not necessarily have to be about vaccination).
So the right way to formulate your search is:
vaccination AND (swine flu OR H1N1)
When carrying out extensive searches, using brackets will soon become complicated. You lose track and before you know it, you have put a bracket in the wrong place. It is better to first search with separate search terms, and combine them later. To this end you can use the function 'History and search details', where you can make the combinations between elements of your search. For the first part, click on the bullets under the 'Actions'-button. Click on 'Add query'. For the second element you want to combine, you'll see options to combine with AND or OR.