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Systematic Reviews

Develop a Focused Research Question

Frameworks have been designed to structure research question.  PICO framework has been applied commonly to help user to easily identify the key concepts of the research question. If your question cannot fit into PICO, an alternative is to use the concept framework, i.e. to identify the key concepts involved and structure the search accordingly based on these key concepts.  

It is important to discuss with a librarian to find out more on how to structure a focused question and conduct a preliminary search  using these key concepts to ensure that there are enough studies before doing a review.

PICO for quantitative studies

PICO is a useful tool for asking quantitative focused questions and to translate the search question into search concepts.

Here is an example on how to formulate a research question using the PICO formulation:

Topic: Sleep quality of dementia patient

Example of less specific research question: How to improve sleep quality of dementia patient?

Your initial search terms might be : Sleep quality AND dementia

Example of a specific research question: Light therapy for improving cognition, activities of daily living, sleep, challenging behaviour, and psychiatric disturbances in dementia. Source: https://pubmed.ncbi.nlm.nih.gov/24574061/

With the specific type of intervention ('light therapy'), the initial search terms can then be changed to: (light therapy OR phototherapy) AND dementia.  The PICO/PECO elements are presented as follows: 

PICO/PECO Elements Question: Light therapy for improving cognition, activities of daily living, sleep, challenging behaviour, and psychiatric disturbances in dementia.
P Problem/population Dementia
I/E Intervention /Exposure Light therapy
C Control, Comparison Usual care
O Outcome Improving cognition, activities of daily living, sleep, challenging behaviour, and psychiatric disturbances
Framework Elements Source Diciplines
PICO Patient
Intervention
Comparison
Outcome

Eriksen, M. B., & Frandsen, T. F. (2018). The impact of patient, intervention, comparison, outcome (PICO) as a search strategy tool on literature search quality: a systematic review. Journal of the Medical Library Association : JMLA106(4), 420–431. https://doi.org/10.5195/jmla.2018.345

Clinical medicine
PICO+

Patient
Intervention
Comparison
Outcome

+context, patient values, and preferences

Bennett, S., & Bennett, J. W. (2000). The process of evidence‐based practice in occupational therapy: Informing clinical decisionsAustralian Occupational Therapy Journal, 47(4), 171-180. Occupational therapy
PICOC

Patient
Intervention
Comparison
Outcome

Context

Petticrew, M., & Roberts, H. (2006). Systematic reviews in the social sciences: A practical guide. Malden, MA: Blackwell Publishers.  Social Sciences
PICOS

Patient
Intervention
Comparison
Outcome

Study Type

Methley, A. M., Campbell, S., Chew-Graham, C., McNally, R., & Cheraghi-Sohi, S. (2014). PICO, PICOS and SPIDER: a comparison study of specificity and sensitivity in three search tools for qualitative systematic reviewsBMC health services research14, 579. https://doi.org/10.1186/s12913-014-0579-0 Medicine
PICOT

Patient
Intervention
Comparison
Outcome

Time

Riva, J. J., Malik, K. M., Burnie, S. J., Endicott, A. R., & Busse, J. W. (2012). What is your research question? An introduction to the PICOT format for cliniciansThe Journal of the Canadian Chiropractic Association56(3), 167–171. Education, health care
PICO specific to diagnostic tests Patient/participants/population
Index tests
Comparator/reference tests
Outcome
Kim, K. W., Lee, J., Choi, S. H., Huh, J., & Park, S. H. (2015). Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers - Part I. General guidance and tips. Korean Journal of Radiology, 16(6), 1175-1187. Diagnostic questions

 

Adapted from :Foster, M. & Jewell, S. (Eds). (2017). Assembling the pieces of a systematic review: Guide for librarians. Medical Library Association, Lanham: Rowman & Littlefield. p. 38-39, Table 3.3

Other Frameworks

The PEO question format is useful for answering aetiology or risk reviews.

Here is an example on how to formulate a more specific research question using the PEO formulation:

Topic: Association of sleep duration in middle and old age with incidence of dementia 

Source: https://www.nature.com/articles/s41467-021-22354-2 

PEO Elements Example

P

Population

Aged between 50-70 (middle and old age) 

E

Exposure

Sleep duration (less than 6 hours compared to normal) 

O

Outcome

Dementia 

Based on this example, the initial search terms proposed might be: sleep AND dementia

Khan, K. S., Kunz, R., Kleijnen, J., & Antes, G. (2003). Systematic reviews to support evidence-based medicine: How to review and apply findings of healthcare research. London: Royal Society of Medicine Press.

 

Using the SPIDER tool enabled us to search the literature in this exploratory study in a more timely and sensitive manner because of the suitability of the refined components for qualitative and mixed-methods research.  

Here is an example on how to formulate a more specific research question using the SPIDER formulation:

Topic: First-time parents’ prenatal needs for early parenthood preparation-A systematic review and meta-synthesis of qualitative literature 

Source: https://www.sciencedirect.com/science/article/pii/S0266613816300341 

SPIDER Elements Example
S Sample First-time parents
PI Phenomenon of interest antenatal education 
D Design Interview
E Evaluation  experience 
R Research Type  qualitative 

Based on this example, the initial search terms proposed might be: “first-time parents” AND “parenthood preparation” (i.e. combining the search using S and PI). Depending on the number of results retrieved, the other elements ( D, E and R) can be added later on to look for a specific type of study related to the main focus.

Cooke A, Smith D, Booth A. Beyond PICO: The SPIDER tool for qualitative evidence synthesis. Qualitative Health Research 2012;22(10):1435-43. doi: 10.1177/1049732312452938

SPICE was developed in the context of evidence-based librarianship and subsequently promoted by the Joanna Briggs Institute for qualitative systematic reviews

Here is an example on how to formulate a more specific research question using the SPICE formulation:

Topic: A systematic review of qualitative evidence of cancer patients’ attitudes to mindfulness 

Source: https://onlinelibrary-wiley-com.libproxy1.nus.edu.sg/doi/10.1111/ecc.12783  

SPICE Elements Example
S Setting Clinical setting
P Perspective Experiences, perspectives or attutudes of mindfulness interventions following a cancer diagnosis 
I Intervention Mindfulness and cancer care
C Comparison  control group 
E Evaluation

(1) Coping strategies developed through mindfulness  

(2) Positive outcomes of mindfulness practice  

(3) Challenges with engaging in mindfulness practice  

(4) Group identification and shared experiences 

Based on this example, the initial search terms proposed might be: mindfulness AND cancer AND diagnos* AND (coping OR outcome OR challeng* OR experience) 

Booth A. Clear and present questions: formulating questions for evidence based practice. Library Hi Tech 2006;24(3):355-68. doi: 10.1108/07378830610692127

ECLIPSE search strategy was introduced to handle health management topics.

Here is an example on how to formulate a more specific research question using the ECLIPSE formulation:

Topic: Interventions to improve discharge from acute adult mental health inpatient care to the community: systematic review and narrative synthesis 

Source: https://bmchealthservres.biomedcentral.com/articles/10.1186/s12913-019-4658-0 

ECLIPS(E) Elements Example
E Expectation Interventions to improve the discharge procedure from the hospital to the community where rehabilitation will continue.
C Client Acute mental health inpatient
L Location Community care 
I Impact Reduced readmission, improved wellbeing, reduced homelessness, improved treatment adherence, accelerated discharge, reduced suicide. 
P Professionals Hospital nurses, community staff, social services.
S Service

Community services particularly for rural community services 

Based on this example, the initial search terms proposed might be: "mental health" AND discharg* AND intervention*

Wildridge, V., & Bell, L. (2002). How CLIP became ECLIPSE: A mnemonic to assist in searching for health policy/management information. Health Information & Libraries Journal, 19(2), 113–115. https://doi.org/10.1046/j.1471-1842.2002.00378.x

SDMO approach is used in methodology systematic reviews or any evidence syntheses to examine any methodological issues relating to the design, conduct and review of research studies.

Topic: Characteristics of Qualitative Descriptive Studies: A Systematic Review

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5225027/  

SDMO Elements Example
S Studies Qualitative Descriptive (QD) Studies
D Data Individual and/or focus-group interviews that were semi structured.
M Methods Report on specific characteristics of methods and findings reported in journal articles self-identified as QD and published during one calendar year. 
O Outcomes Differences of each QD methods and how other researchers had combined QD with other methods. Justification for how QD was chosen in the paper

Based on this example, the initial search terms proposed might be: "qualitative descriptive" AND "Nursing".  These search terms can be combined with 2nd concept such as nursing or allied health or hearing loss, etc.

Munn, Z., Stern, C., Aromataris, E. et al. What kind of systematic review should I conduct? A proposed typology and guidance for systematic reviewers in the medical and health sciences. BMC Med Res Methodol 18, 5 (2018). https://doi.org/10.1186/s12874-017-0468-4

The CoCoPop question format is useful for answering prevalence and incidence reviews.

Here is an example on how to formulate a more specific research question using the CoCoPop  formulation:

Topic:   The prevalence of dementia in urban and rural areas of China

Source:  https://pubmed.ncbi.nlm.nih.gov/23871765/

CoCoPop Elements Example
Co Condition dementia
Co Context urban and rural areas of China
Pop Population  Chinese population

Based on this example, the initial search terms proposed might be: (prevalence OR incidence) AND Dementia AND (China OR Chinese)

Munn Z, Moola S, Lisy K, et al. Methodological guidance for systematic reviews of observational epidemiological studies reporting prevalence and cumulative incidence data. Int J Evid Based Healthc 2015;13(3):147-53. doi: 10.1097/XEB.0000000000000054

The PFO question format is useful for answering prognostic studies.

Here is an example on how to formulate a more specific research question using the PEO formulation:

Topic:  The prognostic and diagnostic utility of tests of platelet function for the detection of 'aspirin resistance' in patients with established cardiovascular or cerebrovascular disease: A systematic review and economic evaluation

Source: https://www.journalslibrary.nihr.ac.uk/hta/hta19370/#/full-report  

PFO Elements Example
P Population Patients aged ≥ 18 years on aspirin (as monotherapy or in combination with other antiplatelet agents), with established cardiovascular disease or CVD, or diabetes. Studies with mixed populations were included as long as data for relevant patients were extractable. Studies with patients on aspirin for peripheral vascular disease were noted.
F Prognostic Factors (or models of interest) Studies reporting prognostic models, in which a platelet function tests (PFT) was one of multiple prognostic factors predicting clinical outcomes in a population of interest, were eligible for review, in order to examine the contribution of the PFT to the overall performance of the prognostic model, and to establish whether or not predictive accuracy of clinical outcomes was improved by combining test results with other prognostic factors.
O Outcome Clinical outcomes, such as vascular events [non-fatal and fatal ischaemic stroke, TIA, systemic embolism (pulmonary embolism, peripheral arterial embolism), MI, revascularisation procedures]; haemorrhagic events; all-cause mortality; mortality due to vascular events; composite outcomes containing the above [e.g. major adverse cardiac events (MACEs)].

Based on this example, the initial search terms proposed might be: (predictor* OR prognos*) AND "platelet function" AND ("cardiovascular disease" OR diabetes)

Dretzke J, Ensor J, Bayliss S, et al. Methodological issues and recommendations for systematic reviews of prognostic studies: an example from cardiovascular disease. Syst Rev 2014;3:140. doi: 10.1186/2046-4053-3-140 [published Online First: 2014/12/04]