- There are a range of situations where evidence is needed to enhance practice
- There are different types of questions to yield different information
- It is important to focus questions
- Use the PICO or SPICE framework to assist question development


(CASP, 2002, p10)
Population: the situation, population or person you are interested in (for example, elderly in-patients with problems of compliance with treatment). They may seem easy to identify, however, without explicit description of who the population is, the clinician can get off on the wrong foot in searching. Careful consideration of the patient and the setting of interest is a good idea. Limiting the population to a certain age group or other special subgroup is also useful.
Intervention: the thing that you think will make a difference, for instance - a self-medication training package (an intervention may not always be required or appropriate, depending on the type of question). The intervention may include but is not limited to: any exposure, treatment, patient perception, diagnostic test, or prognostic factor. The more specifically the intervention of interest is defined, the more focussed the search will be.
Comparison: the comparison is measured against the intervention (a comparison is not always required or appropriate depending on the type of question). The comparison needs special consideration. The comparison can be a true control, such as a placebo. More commonly the comparison is another treatment, sometimes the usual standard of care. For example a comparison to the ‘self training medical package’ could be nurse delivered instructions. If there is no standard of care, the comparison may be ‘no treatment’ or ‘no intervention’ .
Outcome: the outcome is the end point of interest.
Specifically identifying the outcome enables the researcher to find evidence that examined the same outcome variable. This is important because sometimes a variable may be measured in different ways. For example, smoking cessation may be measured in terms of the proportion of people who quit for 3 months, or the average reduction in cigarettes smoked per person over 3 months.
Melnyk, B.M. & Fineout-Overholt, E. 2005, Evidence-based practice in nursing & healthcare: a guide to best practice, Lippincott Williams & Wilkins, Philadelphia.
Critical Appraisal Skills Programme. (CASP) (2002) Evidence-based Health Care, CASP: Milton Keynes
The patient population or disease of interest:
The intervention used in the study, if applicable
The alternative to the intervention (such as the comparison) if applicable
Outcome of interest for example:
These are some examples of outcome that may be specified. It is important to make your outcome specific, to save wasting search time. However, the tricky part is to be specific enough to avoid wasting time but not so specific that you fail to find potentially useful research. Start by taking a quite narrow focus, then if this doesn’t find enough useful research, try widening your search bit by bit.
Melnyk, B.M. & Fineout-Overholt, E. 2005, Evidence-based practice in nursing & healthcare: a guide to best practice, Lippincott Williams & Wilkins, Philadelphia.
Population | Intervention | Comparison | Outcome |
---|---|---|---|
Rent boys < 25 years Glasgow |
Saliva HIV testing intervention Street based |
Blood HIV testing intervention Clinic based |
Know which service is more acceptable to population |
Here is a PICO framework completed for one topic which may lead to the practice based question of :
How acceptable would a street-based saliva HIV testing intervention be to rent boys under 25 in Glasgow compared to a clinic based service?
It may also help you to identify and focus your practice based question by considering what type of question you can ask about your topic. Here are six types of questions that could be asked, with examples. The population, intervention, comparison and outcome for each question is pointed out to further show the use of the PICO framework . This shows how using both PICO and considering the question type can help you to develop a focused practice based question.
Therapy questions
Causation questions
Diagnostic question
Prevention question
Prognosis question
Meaning and experiences
The next section will look at SPICE in detail and give you some general pointers and conclusions.