Develop search termsusing PICO & PEO formats

Planning your search

Selecting appropriate search terms is the key to successful literature searching.

Without meaningful search terms you are unlikely to find useful articles. Rubbish in = rubbish out.

The PEO, PICO and SPICE formats are used widely in nursing and health research. They help you formulate your research question and identify the key concepts from which to develop appropriate search terms.

PEO example

Topic: Quality of life in older people living with a stoma

P Older people

E Stoma

O Quality of life

For each concept try to think of as many similar or related words as possible.

PEO example

Topic: Quality of life in older people living with a stoma

P Older people OR elderly OR ageing OR aged

E Stoma OR colostomy OR ostomy OR ileostomy

O Quality of life OR QOL OR experiences OR daily life

These are the key search words which will form the basis of your search strategy.

PICO example

Topic: Use of acupuncture as aid to stop smoking

P Smokers

I Acupuncture

C Other alternative therapies

O Stop smoking

For each concept try to think of as many similar or related words as possible.

Worked PICO example

Topic: Use of acupuncture as aid to stop smoking

P Smokers, nicotine, tobacco

I Acupuncture, acupoint

C Other alternative therapies, complementary therapies

O Stop, cease, cessation, quit, withdrawal

These are the key search words which will form the basis of your search strategy.

Search words to avoid

Keep things simple - do not try to overcomplicate your search with unnecessary search words.

These are not key concepts and need not normally be used:

Problems with Impact on

Effects on The affect of

Role of The link between

Implications for Compare with

Only use phrase like these if there is other way to limit a large set of search results.

Free-text searching

For best results use free text search terms - these are your own search words.

Free text searching enables quick, easy and very comprehensive searching. It may be your only option if subject headings or thesaurus terms are unavailable.

You may need to enter lots of different search terms and you may sometimes find some articles that are not relevant.

You will also need to differentiate between USA and UK spelling and terminology.

Synonyms and related words

To search comprehensively, you should use various types of search terms e.g.

Synonyms (similar words)

e.g. for older use elderly, aged or later life

Antonyms (opposite words)

e.g. for success use failure

Alternative search words

Acronyms and abbreviations

e.g. use QOL for quality of life

Alternative spellings

e.g. use anemia for anaemia

Broader & narrower terms

e.g. use body weight for obesity

e.g. use melanoma for cancer

Different terminology

Differences in terminology across national boundaries, e.g. for accident and emergency use emergency room

Old and new terminology e.g. for mongolism use down syndrome

Brand and generic names e.g. for coumadin use warfarin

Lay and medical terminology e.g. for stroke use cerebrovascular accident

Subject headings

Subject headings searching is an alterative to free-text keyword searching. It is useful for finding articles which use different terminology.

Subject headings are used to index articles in databases e.g. heart attack may be indexed under myocardial infarction

There is less need to think about all the different search terms that may be used e.g. to describe an illness.

See presentation on Subject headings for more information.