Defining the research question and developing a protocol are the essential first steps in your systematic review. The success of your systematic review depends on a clear and focused question, so take the time to get it right.
PICO may be the most well-known model framework: it has its origins in epidemiology and now is widely-used for evidence-based practice and systematic reviews.
PICO normally stands for Population (or Patient or Problem) - Intervention - Comparator - Outcome.
| Population defines the group you are studying. It may for example be healthy adults, or adults with dementia, or children under 5 years of age with asthma. |
| Intervention is the type of treatment you aim to study, e.g. a medicine or a physical therapy. |
| Comparator is another type of treatment you aim to compare the first treatment with, or perhaps a placebo. |
| Outcome is the result you intend to measure, for example (increased or decreased) life expectancy, or (cessation of) pain. |
SPICE is used mostly in social science and healthcare research. It stands for Setting - Population (or Perspective) - Intervention - Comparator - Evaluation. It is similar to PICO and was devised by Booth (2004).
| Setting: the location or environment relevant to your research (e.g. accident and emergency unit) |
| Population (or perspective): the type of group that you are studying (e.g. older people) |
|
Intervention: the intervention/practice/treatment that you are evaluating (e.g. initial examination of patients by allied health staff) |
| Comparator: an intervention with which you compare the above comparator (e.g. initial examination by medical staff) |
| Evaluation: the hypothetical result you intend to evaluate e.g. lower mortality rates) |
The examples in the SPICE table are based on the following research question: Can mortality rates for older people be reduced if a greater proportion are examined initially by allied health staff in A&E?
Source: Booth, A (2004) Formulating answerable questions. In Booth, A & Brice, A (Eds) Evidence Based Practice for Information Professionals: A handbook. (pp. 61-70) London: Facet Publishing.
SPIDER was adapted from the PICO framework in order to include searches for qualitative and mixed-methods research. SPIDER was developed by Cooke, Smith and Booth (2012).
| Sample: qualitative research may have fewer participants than quantitative research and findings may not be generalised to the entire population. |
| Phenonemon of Interest: experiences, behaviours or decisions may be of more interest to the qualitative researcher, rather than an intervention. |
| Design: the research method may be an interview or a survey. |
| Evaluation: outcomes may include more subjective ones, e.g. attitudes. |
| Research type: the search can encompass qualitative and mixed-methods research, as well as quantitative research. |
Source: Cooke, A., Smith, D. & Booth, A. (2012). Beyond PICO: the SPIDER tool for qualitative evidence synthesis. Qualitative Health Research(10), 1435-1443. http://doi.org/10.1177/1049732312452938.
Module 1 in Cochrane Interactive Learning explains the importance of the research question, some types of review question and the PICO framework. The Library is subscribing to Cochrane Interactive Learning.
