A systematic review is a method of synthesizing scientific evidence. Systematic reviews of animal-based studies help to improve the quality of science. They also contribute to the reduction and refinement of animal use in science.
Synthesis refers to “the contextualization and integration of research finds of individual research studies within the larger body of knowledge on the topic. A synthesis must be reproducible and transparent in its methods”. Systematic reviews are one form of synthesis. (see the Canadian Institute of Health Research).
Systematic reviews of animal-based studies originated from a process that is widely used in human medicine to assess the effectiveness of health care interventions and forms the foundation for evidence-based medicine (see the Cochrane Collaboration and the Canadian Cochrane Collaboration). Systematic reviews of animal-based studies are rare compared with the clinical field and most originate from the CAMARADES group. Systematic reviews can be applied to animal-based studies in areas such as basic and applied research, testing, and the use of animals in education.
In August 2011, support for the increased use of synthesis of evidence reviews in animal-based research was expressed in the Montréal Declaration on the Synthesis of Evidence, adopted by the participants of the 8th World Congress in Alternatives to Animal Use in the Life Science. It is a call for a change in the culture of planning, executing, reporting, reviewing and translating animal research.
Participants agreed that global adoption of a process of synthesis of evidence to review animal studies would:
Conducting Systematic Reviews
The quality of a systematic review is dependent on the quality of the primary studies. Insufficient reporting of methodology and/or poor design in primary studies will hamper a systematic review. Many resources for reporting of primary studies are available There are also resources to assist in conducting and assessing systematic reviews and examples of published systematic reviews of animal studies.
Henderson V.C., Kimmelman J., Fergusson D., Grimshaw J.M. and Hackam D.G. (2013) Threats to validity in the design and conduct of preclinical efficacy studies: a systematic review of guidelines for in vivo animal experiments. PLOS Medicine 10(7): e1001489.
Hooijmans C.R., Leenaars M. and Ritskes-Hoitinga M. (2010) A gold standard publication checklist to improve the quality of animal studies, to fully integrate the Three Rs, and to make systematic reviews more feasible. Alternatives to Laboratory Animals (ATLA) 38(2):167-182.
Kilkenny C., Browne W.J., Cuthill I.C., Emerson M. and Altman D.G. (2010) Improving Bioscience Research Reporting: The ARRIVE Guidelines for Reporting Animal Research. PLoS Biology 8(6).
Landis S.C. et al. (2012) A call for transparent reporting to optimize the predictive value of preclinical research. Nature 490:187-191
National Research Council (2011) Guidance for the Description of Animal Research in Scientific Publications.
The ARRIVE guidelines - Examples. Animal Research: Reporting In Vivo Experiments
Cochrane Collaboration, The (2012) Essential resources for review authors.
Leenaars M., Hooijmans C.R., van Veggel N., ter Riet G., Leeflang M., Hooft L., van der Wilt G.J., Tillema A. and Ritskes-Hoitinga M. (2012) A step-by-step guide to systematically identify all relevant animal studies. Laboratory Animals 46(1):24–31.
Mignini L.E. and Khan K.S. (2006) Methodological quality of systematic reviews of animal studies: a survey of reviews of basic research. BMC Medical Research Methodology 6:10.
Moher D., Liberati A., Tetzlaff J. and Altman D.G. (2009) Preferred reporting items for systematic reviews and meta-analyses: The PRISMA Statement. PLoS Med 6(7).
Mulrow C.D. (1994) Rationale for systematic reviews. BMJ 309(6954):597-599.
Peters J.L., Sutton A.J., Jones D.R., Rushton L. and Abrams K. R. (2006) A systematic review of systematic reviews and meta-analyses of animal experiments with guidelines for reporting. Journal of Environmental Science and Health Part B 41(7):1245–1258.
Radboud University (2012) SYRCLE (Systematic Review Centre for Laboratory animal Experimentation).
Shea B.J., Grimshaw J.M., Wells G.A., Boers M., Andersson N., Hamel C., Porter A.C., Tugwell P., Moher D. and Bouter L.M. (2007) Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews. BMC Medical Research Methodology 7:10.
de Vries, RBM et al. (2014) The Usefulness of Systematic Reviews of Animal Experiments for the Design of Preclinical and Clinical Studies. ILAR Journal 55(3): 427-437. doi: 10.1093/ilar/ilu043
Ahmed K., Jawad M., Abboudi M., Gavazzi A., Darzi A., Athanasiou T., Vale J., Khan M.S. and Dasgupta P. (2011) Effectiveness of procedural simulation in urology: A systematic review. The Journal of Urology 186(1):26-34.
Blackman K., Brown S.G. and Wilkes G.J. (2001) Plasma alkalinization for tricyclic antidepressant toxicity: a systematic review. Emergency Medicine 13(2):204-10.
Horn J., de Haan R.J., Vermeulen M., Luiten P.G and Limburg M. (2001) Nimodipine in animal model experiments of focal cerebral ischemia: a systematic review. Stroke 32(10):2433–2438.
Krauth D., Woodruff T.J. and Bero L. (2013) Instruments for assessing risk of bias and other methodological criteria of published animal studies: a systematic review. Environmental Health Perspectives 121(9):985–992.
Lucas C., Criens-Poublon L.J., Cockrell C.T. and de Haan R.J. (2002) Wound healing in cell studies and animal model experiments by Low Level Laser Therapy; were clinical studies justified? a systematic review. Lasers in Medical Science 17(2):110-134.
Mapstone J., Roberts I. and Evans P. (2003) Fluid resuscitation strategies: a systematic review of animal trials. Journal of Trauma-Injury Infection & Critical Care 55(3):571-589.
Patronek G.J. and Rauch A. (2007) Systematic review of comparative studies examining alternatives to the harmful use of animals in biomedical education. Journal of the American Veterinary Medical Association (JAVMA) 230(1):37–43.
Percie du Sert N., Rudd J.A., Apfel C.C., Andrews P.L. (2011) Cisplatin-induced emesis: systematic review and meta-analysis of the ferret model and the effects of 5-HT3 receptor antagonists. Cancer Chemotherapy and Pharmacology 67(3):667–686.
Perel P., Roberts I., Sena E., Wheble P., Briscoe C., et al. (2007) Comparison of treatment effects between animal experiments and clinical trials: systematic review. BMJ 334(7586):197.
Sena E.S., Briscoe C.L., Howells D.W., Donnan G.D., Sandercock P.A.G. and Macleod M.R. (2010) Factors affecting the apparent efficacy and safety of tissue plasminogen activator in thromboticocclusion models of stroke: systematic review and meta-analysis. Journal of Cerebral Blood Flow and Metabolism 30(12)1905-1913.
Van der Worp H.B., Sena E.S., Donnan G.A., Howells D.W. and Macleod M.R. (2007) Hypothermia in animal models of acute ischaemic stroke: a systematic review and meta-analysis. Brain 130(12):3063–3074.
Vesterinen H.M., Sena E.S., Egan K.J., Hirst T., Churolov L., Currie G., Antonic A., Howells D.W. and Macleod M.R. (2013) Meta-analysis of data from animal studies: A practical guide. Journal of Neuroscience Methods 221:92-102.