Library Tutorial for Nursing

Section 8. Advanced searching for higher degree students.

When you embark on a higher degree the dreaded literature review will loom large in your early preparations. It can seem rather daunting, but if you follow a few simple rules you'll save time, and avoid a lot of confusion and frustration. Essentially you are dealing with two simple components - language, and logic. This page is to help you with both.

Language - trawling PubMed for terms

Logic - constructing your search from the terms you've collected

Useful tips - to save you time

Other databases - moving on from PubMed to Scopus (my favourite) and other sources

Language

One of the problems we all have is that we expect other people to call things by the same name that we do. Even if they don't, in normal conversation this is not a problem, as we rapidly process the alternatives as equivalents. So if I talk about sickness, and you talk about illness it really doesn't matter, as we still understand one another. Databases (with very few exceptions) don't work like this. Instead they search only the exact words we use (including misspellings!). This means that for comprehensive searching you need to provide them with as many possible alternatives as you can. Some of them (like PubMed and CINAHL) even have their own indexing language, or thesaurus which needs to be considered as well. PubMed has a thesaurus which is called MeSH - which is simply an acronym for Medical Subject Headings.

I'm starting with PubMed (help with searching CINAHL is on another page), and the topic I've chosen is - nursing management of fatigue in cancer patients.
Most postgraduate topics will have more components than this, but I'm using a simple example to demonstrate general principles.
At this stage we will just explore the language you'll need to use in your search, without worrying about how many, or how few articles your retrieve, or even how relevant most of them are.

Method

• Open a Word document and set up a logic grid - you'll need a column for each concept.

A	B	C
cancer	fatigue	nursing

• Perform a simple search, using your own words - cancer AND fatigue AND nursing

• Scroll through the results to see if there are any articles that look as if they're on your topic. What you'll need is one that includes

(PubMed - indexed for MEDLINE)

Very new material will be labelled either

(PubMed - as supplied by publisher)

or
(PubMed - in process)

and will not have indexing (MeSH) terms added to it.

• Once you have found a suitable article click on the title. This will display the article details, plus its abstract, and a link to enable you to view MeSH Terms

• Clicking on the + sign will allow you to see the indexing (MeSH) terms which have been used to describe the content of the article.
  The article I will use here is

Fatigue and physical activity in older patients with cancer: a six-month follow-up study.
Luctkar-Flude M, Groll D, Woodend K, Tranmer J.
Oncol Nurs Forum. 2009 Mar;36(2):194-202.

and the indexing is

Terms with an asterisk after them are Major terms, and represent the most important subject aspects of the article. Those without an asterisk are Minor terms, and represent less important aspects of the article's content.

Some of the indexing terms in this example have subheadings - for example /prevention & control.

When searching, using subheadings is very risky, as indexing at this level is rather variable. However prevention & control is an exception to the rule, and is available only as a subheading

• Check it out in MeSH - there's a link to the MeSH Database in the drop down box from the Search box

• Look up fatigue in MeSH

• Look up cancer as a MeSH
  You'll find that MeSH uses Neoplasms rather than the term cancer. Under neoplasms you'll see a huge list of more specific subcategories. If you want to search all categories it's very easy, as PubMed's default is to do what's called exploding MeSH terms, and it will search all of the terms in the list of neoplasms - much easier than typing them into your search one by one!!

• Look up nursing as a MeSH. Nursing also has a list of more specific categories which will be searched

• Now udate your logic grid

A	B	C
neoplasms[mh]	fatigue[mh]	nursing[mh]

• Repeat this process with other articles which look relevant to see whether consistent indexing patterns emerge, and to extend your range of MeSH.

As new material in PubMed is not indexed, and as indexers, being human, are prone to error, or variation in the way they interpret the content of an article, words in titles and abstract need to be searched too.

• Add terms to the logic grid to allow for this - the list below is not intended to be comprehensive, but will give you an idea of how to build a search. If phrases are to be searched in titles and abstracts, inverted commas must be used to enclose the phrase, and ensure that words are not searched independently.

A	B	C
neoplasms[mh] neoplasm*[tiab] cancer*[tiab] carcinoma*[tiab] malignan*[tiab] tumour*[tiab] tumor*[tiab] oncolog*[tiab]	fatigue[mh] fatigue*[tiab] exhaustion[tiab] "lack of energy"[tiab] tiredness[tiab] weakness[tiab]	nursing[mh] nursing[tiab] nurse*[tiab]

There's also a complication with the logic of this search as there is a MeSH available which covers the subject matter of two of the columns - oncologic nursing
How would you deal with this?

The easiest way would be to construct a separate logic grid, perform a separate search, then "OR" it with your first search

Logic

When you have finished collecting terms you are ready to search. PubMed requires that Boolean operators are in upper case, so it's important when searching PubMed to use AND, OR, NOT to connect your search terms. PubMed's tutorial gives a clear explanation of how Boolean logic works.

You will need to OR the individual words in each column, and then AND the groups of words together - remembering to use brackets around the groups of terms from each column to preserve the logic of your search.

Useful Tips

• Click on Details to see how PubMed has interpreted your search

• Use the Citation display to see MeSH terms for articles

• Add [mh] when searching for Mesh terms
  eg. neoplasms[mh]

• Use [mh:noexp] if you don't want to explode the search term
  eg. neoplasms[mh:noexp] will search only for the term Neoplasms, not those in the list below

• Use [majr] to restrict your search to major indexing terms only
  eg. neoplasms[majr]

• Use [tiab] to search for words in titles and abstracts - this is essential for searching the most recent literature
  eg. neoplasm*[tiab]

• Expert Searching in PubMed
  This is a single page guide produced by the Countway Library at Harvard University. Don't be put off by the "expert" - it's a very useful and easy to follow guide with lots of examples to help you to take advantage of PubMed's incredible search power.

Other databases

There may well be databases, apart from PubMed and CINAHL, that are useful for your topic, and I've included a list of additional databases I think may be relevant for nursing.

The biggest of these is Scopus, and although it doesn't have the sophisticated subject search capability of PubMed or CINAHL it has some extremely useful features which will allow you to extend your search with very little effort.

• Try copying the title of a really good article from PubMed, and pasting it (enclosed in inverted commas) into the Scopus Search box.

• Set the in box to Article Title, and search

• Once the result is displayed click on Abstract +Refs

This will allow you to see

• the abstract for the article

• articles which have cited this article,

• the list of references from the bibliography at the end of the article, along with a link to other articles which have cited each reference

Each reference in the list also has links to full text, as well as its own abstract and references.