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Systematic literature studies, Health & Sport

Library subject page. The University Library, Agder University

1. What - Your search question - and main search concepts

Formulate a Question

Focus your search question and choose the main search concept from your question, using framework like the PICO or similar. The framework is used to focus your question and to structure the search in the database.  Different framework below

PICO framework to formulate the search question and structure the search

PICO or similar framework is used for

  1. Formulate, focusing the search question and decide about the main search question
  2. Decide inclusion and exclusion criteria
  3. Structuring the search in the database
P Population - or problem. (Age, sex, diagnosis)
I Intervention, or Exposition, or risk factor, or Issue - or phenomena of Interest  - or Instrument
C Comparison, or Context or setting
O Outcomes, results - or experiences (or evaluation, or measurement properties)
T Time  (or type of study)
S Study design (or settings)


  • It's not all question that includes all the elements, and it is not either necessary or desirable to search with words for all the elements. For a broad sensitive search, include 2-3 elements, consider the amount of literature and your review aim
  • If it's difficult to frame your search question with PICO or similar - use Who, What and Why. The main thing is to find the different elements, pieces in your question. You need to break down your search question into search concepts.


from Bramer et al 2018:

"Elements in a search strategy do not necessarily follow the patient, intervention, comparison, outcome (PICO) structure or any other related structure. Using the PICO or another similar framework as guidance can be helpful to consider, especially in the inclusion and exclusion review stage of the SR, but this is not necessary for good search strategy development"

"Not all elements of a research question should necessarily be used in the search strategy. Some elements are less important than others or may unnecessarily complicate or restrict a search strategy. Adding an element to a search strategy increases the chance of missing relevant references. Therefore, the number of elements in a search strategy should remain as low as possible to optimize recall"


Bramer, W. M., de Jonge, G. B., Rethlefsen, M. L., Mast, F., & Kleijnen, J. (2018). A systematic approach to searching: an efficient and complete method to develop literature searches. Journal of the Medical Library Association: JMLA, 106(4), 531–541.

  1. P - Population, problem
  2. E - Exposition / Issue / Interest 
  3. O - Outcome
  4. (S = Study design)

Or for questions about experiences or percpetions (qualitative studies)

  1. Population: Older people
  2. Exposition: Cancer
  3. Outcome: Patients views, experiences etc.
  4. (S  - Study design)

From: Bettany-Saltikov, J., & McSherry, R. (2016). How to do a systematic literature review in nursing : A step-by-step guide (2nd ed.). London: Open University Press. S. 24. 

For qualitative questions, or use the PEO framework

  1. Population
  2. phenomen of Interest
  3. Context
  4. (S - Study design)


Population (nurses)
phenomen of Interest (views or attitudes towards, or experiences on, relatives witnessing resuscitation)
Context (emergency room)
Question: What are nurses (P) views or attitudes (I) towards relatives witnessing resuscitation (I) in emergency rooms (Co)

p. 33, Aveyard, 2019. Doing a literature review in health and social care. Open University Press

Search with a block for qualitative studies/designs:

Possible often used words:

qualitative OR phenomenolog* OR interview* OR experienc* OR themes OR thematic OR Ethnographic* OR Ethnological* OR "grounded theor*" OR ethnonursing*  OR  audiorecording* OR hermeneutic* OR "content analys*" OR "focus group*"

In some cases - just a population and experiences.  You can also use the PEO, PIO or PICo


  • P: children of parents with a severe mental illness
  • O: experience their lives
  • (S: Study design)

Q: how  do children of parents with a severe mental illness experience their lives

S- Study design, Qualitative studies: Exampel search words: 

  • qualitative OR phenomenolog*  OR interview* OR experienc* OR themes OR thematic OR Ethnographic* OR Ethnological* OR "Grounded Theor*" OR Ethnonursing*  OR  Audiorecording* OR hermeneutic*


  • P: Population/participants
  • C: Concept
  • C: Context

Peters MDJ, Godfrey C, McInerney P, Munn Z, Tricco AC, Khalil, H. Chapter 11: Scoping Reviews (2020 version). In: Aromataris E, Munn Z (Editors). JBI Manual for Evidence Synthesis, JBI, 2020, section, 11.2.2.

  1. S - Setting:
  2. P - Perspective:
  3. I - Intervention:
  4. C - Comparison:
  5. E - Evaluation

SBU:s metodbok. 3.4.1 SPICE

Noyes et al (2022). Chapter 21: Qualitative evidence (Section 21.5 Question development). In: Higgins et al, Cochrane Handbook for Systematic Reviews of Interventions. Link

used for qualitative studies, alternative use PICo, PIO/PEO/PO

  • S - Sample
  • PI - Phenomen of interest
  • D - Design
  • E - Evaluation
  • R - Research type (qualiative, quantiative, or mixed method)


Combine the search element like this for a broad sensitive search: S AND PI AND E AND (D OR R)

C - Construct to be measured, or the name(s) of the measurement instrument: ex pain, ex fatigue
P - Population of interest, examples  patients with multiple sclerose - adult with cognitive impairments
I -  Type of instrument, examples:  self-report questionnaire, laboratory test, observational scales, performance-based instruments, interviews
M - Measurement properities of interest: all measurement properities, examples reliability, validity, consistency, psychometrics ... Example search words

Ex page 20 from: 

Mokkink, L. B., Prinsen, C. A. C., Patrick, D. L., Alonso, J., de Vet, H. C. W., & Terwee, C. B. (2018). COSMIN methodology for systematic reviews of Patient‐Reported Outcome Measures (PROMs) user manual.  Retrieved from 

See also: Vet, H. (2011). Measurement in medicine : A practical guide. Cambridge University Press: Kap, 9, s. 275-311 Systematic review of measurment properites

See also the PCC framework

"Patient Reported Outcome (PRO) er pasientrapporterte utfallsmål som til dømes opplevingar knytt til helse og sjukdom. Patient Reported Outcome Measures (PROM) er skjema som måler korleis pasientane opplever forhold knytt til helse og sjukdom og behandlingseffektar. PROM inkluderer mål på symptom, funksjonsnivå, helsestatus og/eller helserelatert livskvalitet. Pasientrapporterte mål inneberer ikkje alltid å måle eit utfall (outcome). Det kan også vere at ein vil nytte pasientrapporterte mål til dømes for å identifisere pasientar eller grupper som har behov for spesielle intervensjonar" From:

  • P: Population (health condition, diagnose, age)
  • I: Index test
  • R: Referanse standard
  • O: Outcomes

Campbell JM, Kulgar M, Ding S, Carmody DP, Hakonsen SJ, Jadotte YT, White S, Munn Z.  Chapter 9: Diagnostic test accuracy systematic reviews. In: Aromataris E, Munn Z (Editors). Joanna Briggs Institute Reviewer's Manual. The Joanna Briggs Institute, 2017. Available from 

Yao, X., Vella, E. & Brouwers, M. (2018). How to conduct a high-quality systematic review on diagnostic research topics. Surgical Oncology, 27(1), 70-75.


Context - Intervention - Mechanisms - Outcomes - (CIMO) framework) - for use in research synthesis in management and organization studies

Source: Denyer, D., Tranfield, D., & van Aken, J. E. (2008). Developing Design Propositions through Research Synthesis. Organization Studies, 29(3), 393–413.