Formulating a question for systematic reviews Jenny Basford, Systematic Reviews Support Librarian mEsh

The systematic review process Formulate research / policy conclusions Search bibliographic databases Identify possible papers from titles/abstracts Retrieve papers Extract data Further selection of primary studies using inclusion criteria Synthesis Formulate research question Design search strategy Quality appraisal Write protocol

Learning outcomes To understand the importance and purpose of setting out a well-formulated research question To be aware of how bias can impact upon a systematic review from the outset To be able to develop a clear review question

Introduction: formulating a review question A statement of what you are going to do and how you will do it Gives a clear pathway to follow for the rest of the review Thus reduces bias and error

Creating a review question Comprised of two parts: – ‘Free form’ question – Structured question

Free-form question Defined by simple language Sometimes very vague Describes the query that you are interested in – e.g. what effect does statin use have on pregnancy?

Creating a structured research question: PICO(S) Populations Interventions Comparators Outcomes Study design

Populations The group of participants/patients of concern to the reviewer e.g. ‘all children under 16 years’; ‘men with history of heart conditions’

Interventions Actions/exposures e.g. treatments, social or educational interventions, risk factors, tests, drugs, surgical techniques Refined by dosage/duration Can be broad, e.g. ‘dietary supplement’ or specific, e.g. ‘Vitamin D, Cholecalciferol’

Comparators If including comparative studies: don’t always have this Similar definition as intervention Comparison can be: no intervention, placebo, current standard practice or an active comparator: e.g. comparing accuracy of ultrasound vs. MRI scan in diagnosis of adenomyosis

Outcomes Clinical changes in health state, e.g. morbidity, mortality, survival Health resource use Quality of life Behaviour

Study designs ‘major role in determining the reliability of the results’ (CRD) RCTs usually the study design of choice for effectiveness reviews Scoping search will help you decide whether to limit by study type Depends entirely on the nature of your topic

‘Free form’ review question To assess the impact of statin use in pregnant women upon their unborn child

Structured review question: PICOS for statins in pregnancy Population: pregnant women Intervention: statins Comparator: none Outcome: congenital malformations in the child Study design: RCTs

Conclusion Spending time on clearly defining your question at the beginning will help your review by providing a pathway and reducing bias It will ensure everyone on the review is asking the same question