Rapid evidence synthesis during a pandemic, by Dr Barbara Clyne

SARS-CoV-2, the virus that causes COVID-19 has rapidly spread around the world, causing a substantial number of cases and deaths globally. The COVID-19 pandemic requires making rapid decisions based on sparse and rapidly emerging evidence. There has been a proliferation of scientific output in basic science, clinical medicine and public health, in both traditional academic journals and shared on preprint servers. Typically, evidence synthesis teams conduct systematic reviews for guideline developers, clinicians, and policy decision-makers which can take an average of 15 months to complete.(1) The speed at which new COVID-19 studies are becoming available and the urgent need for prompt evidence syntheses to inform decision making has meant that the traditional systematic review is not a feasible option. The urgent need for the prompt production of evidence synthesis, however, should not be done at the cost of quality and one way to ensure this is through the use of rapid reviews of evidence. While delivering outputs in shorter time frames than systematic reviews, several methodological challenges to the conduct of rapid reviews have become apparent during the COVID-19 pandemic such as the urgency of the request, identifying and accessing sources of evidence for inclusion, extrapolation of results from indirect evidence, and rapid dissemination of results.(2)

Our team of researchers at the Health Information and Quality Authority (HIQA) of Ireland, in collaboration with the Department of General Practice, Royal College of Surgeons in Ireland (RCSI) has conducted a series of 10 rapid reviews to date on various public health topics relating to COVID-19, at the request of the National Public Health Emergency Team (NPHET) and or its subgroups or its Clinical Expert Advisory Group to inform national strategic decision-making. In producing these rapid reviews, we have adhered to fundamental methodological principles, in keeping with international rapid review methodology guidance.(3, 4)

In order to address the methodological challenges to the conduct of rapid reviews our approach includes:

  • Agreeing on the protocol for each review with the NPHET Clinical Expert Advisory Group.
  • Publication of the protocol outlining a standardised approach to the process to increase transparency and inform others of our ongoing work to help avoid duplication;
  • Narrowing the scope: limiting the number of populations, interventions and outcomes considered;
  • Parallelisation of tasks: Increasing the intensity of work on review processes where multiple reviewers simultaneously complete review steps, for example, eligibility screening, data abstraction and risk-of-bias assessment;
  • Using review shortcuts: One or more systematic review steps may be reduced or omitted, for example, single eligibility screening as opposed to double screening;
  • Accessing external expert input where appropriate
  • Utilising a quality assurance framework for conduct and sign off on reviews
  • Publication of reviews on the HIQA website, available here.

Quality evidence synthesis is more important than ever. Our work helps ensure rapid access to the best available evidence relevant to the SARS-CoV-2 outbreak to inform decision-making at each stage of the pandemic. As COVID-19 is unlikely to be our last pandemic or public health emergency, we are currently evaluating our experience with rapid evidence synthesis to inform preparedness in future pandemics.

Dr Barbara Clyne is a Research Lecturer at the Department of General Practice, RCSI and is Principal Investigator of a HRB Emerging Investigator Award focused on approaches to the conduct and translation of evidence synthesis to support the development of national clinical guidelines and policy.

The HIQA team comprises a multidisciplinary research team, including a number of SPHeRE alum, and current and incoming scholars: Dr Barbara Clyne, Dr Sinead O’ Neill, Dr Kieran Walsh, Dr Susan Spillane, Dr Paula Byrne, Dr Daniela Rohde, Dr Eamon O’Murchu, Paul Carty, Karen Jordan, James Larkin, Susan Ahern.



  1. Borah R, Brown AW, Capers PL, Kaiser KA. Analysis of the time and workers needed to conduct systematic reviews of medical interventions using data from the PROSPERO registry. BMJ Open. 2017;7(2).
  2. Tricco AC, Garritty CM, Boulos L, Lockwood C, Wilson M, McGowan J, et al. Rapid review methods more challenging during COVID-19: Commentary with a focus on 8 knowledge synthesis steps. Journal of Clinical Epidemiology. 2020.
  3. Garritty C, Gartlehner G, Kamel C, King VJ, Nussbaumer-Streit B, Stevens A, et al. Cochrane Rapid Reviews. Interim Guidance from the Cochrane Rapid Reviews Methods Group. March 2020.
  4. Langlois EV, Straus SE, Antony J, King VJ, Tricco AC. Using rapid reviews to strengthen health policy and systems and progress towards universal health coverage. BMJ Global Health. 2019;4(1):e001178.