5 Searching for Evidence 89
- Use alternative spellings to create an exhaustive search. Remember that
even within the English language, you have spelling variations in American
and British literature. In British literature, Ss often replace Zs, and OUs of-
ten replace Os. Two examples of this are organisation versus organization
and behaviour versus behavior.
- Use limits where appropriate. Most databases have extensive limits pages.
PubMed and CINAHL allow you to limit by age, gender, species, date of
publication, and language. The limit for publication types assists in select-
ing the highest levels of evidence: meta-analysis, practice guidelines, ran-
domized controlled clinical trials, and controlled clinical trials.
- Revise your search. As you move through steps 1–4, you are likely to find
new terms, alternate spellings of keywords, and related concepts. You need
to revise your search to incorporate these changes. Your search is only
complete when you can answer your question. If you were given a previ-
ous search to update, you will need to make revisions, because terms
may have changed over time and new related areas of research may have
developed.
Free Resources
Most databases require a paid subscription, but some are available for free on-
line. Table 5.3 lists quality resources available for free on the Internet. Check
the local medical or public library to see what is accessible. Medical librarians,
knowledgeable about available resources and how each functions, can assist in
the search for evidence and can provide invaluable personalized instruction. Nev-
er be afraid to ask for help! The only foolish question is the one unasked.
