Identifying search terms (concepts and synonyms)

Once the question has been formulated using the PICO method, the next step involves identifying the words that will be used to find information. These are the foundation for your search. You can start your search strategy by keeping a record of significant words while doing background reading on the subject, or by using a thesaurus or dictionary.

Concepts

Concepts are the main topics or headings that emerge from the question. Try to keep to a maximum of four or five concepts to avoid over-complicating the search.

Synonyms

Synonyms are alternative search terms for the same concept. Terms can vary between countries, for example: ‘Accident and Emergency’ in the UK has the same meaning as ‘Emergency Department’ in Australia. Synonyms are included under broad subject headings in sophisticated databases such as MEDLINE, Embase, or PsycINFO. Word spellings may also vary: ‘paediatrics’ in Australia is expressed as ‘pediatrics’ in the USA.

Let’s consider the PICO question: ‘Can brief intervention methods be used as an effective smoking cessation technique with teenagers?’ The following concepts and synonyms can be identified.

	P	I	O
Concepts	Teenagers	Brief Intervention	Smoking Cessation
Synonyms	Adolescents Young people	Brief advice Brief counselling Motivational interview	Stop smoking Quit smoking

More examples

Developing concepts and synonyms from focused clinical questions

Question: Can Cognitive behavioural therapy improve self-esteem in patients with eating disorders?

	P	I	O
Concepts	Eating disorders	Cognitive behavioural therapy	Outcome
Synonyms	Eating disorder(s) Appetite disorder/s Bulimia Anorexia	Cognitive behavioural therapy/ies CBT Talking treatment/therapy	Self esteem Self-worth Self-regard Self confidence

Question: In newborn babies, does a waterbirth increase the risk of morbidity or mortality?

	P	I	O
Concepts	Newborn babies	Waterbirth	Morbidity or mortality
Synonyms	Babies Neonates Newborns Infants	Water immersion Underwater birth Water birth	Death or illness Adverse outcomes