Systematic Evidence Evaluation

Systematic Review

Systematic reviews are reports that assess the best available research on a specific question by synthesizing the results of all relevant studies according to carefully defined and described criteria documented in a Protocol. This process minimizes bias in presenting the best current evidence, thus facilitating better-informed decision-making. Systematic reviews begin with the identification of priority questions by stakeholders from research, governmental, and civil society arenas in a collaborative process. These selected questions are examined using a rigorous methodology to identify and assess all relevant literature, and the findings are then actively disseminated to inform decision-making in research and policy arenas.  The review methods are agreed collaboratively with stakeholders and explicitly defined in advance, to ensure maximum transparency and to enable the methods to be replicated - the basis of good science. This is in contrast with literature reviews which provide no description of how they found, assessed and analysed the references they review and which are therefore not scientific in approach.

Find out more about how OXSREV can help with your systematic review projects Here

Systematic Mapping

Systematic maps are systematically conducted reports that include visual presentations of the availability of robust research of relevance to specific policy or practice questions. They aim to consolidate ‘what is known’ and, unlike a systematic review, they do not assess ‘what works’ because they do not include detailed critical appraisal or data synthesis. Their strength is that by providing a geographical visualisation that can be filtered by aspects of the review question decision-makers can see where research has been neglected either geographically or thematically. In common with systematic reviews, the conduct of a systematic map is driven by a detailed Protocol agreed in collaboration with stakeholders.

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Find out more about how OXSREV can help with your systematic mapping projects Here

Meta-Analysis

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source Savilaasko et al. 2014 

Systematic reviews normally aim to assess ‘what works’ -  the effect of an intervention or exposure, a quantitative synthesis is desirable - and this requires quantitative data synthesis. Meta-analysis is a commonly used statistical technique to pool data from many independent studies. It provides summary effect sizes calculated from several studies.  Each study is weighted in proportion to its sample size so that more weight is given to large studies with precise effect estimates and less weight is given to small studies with imprecise effect estimates. Meta-regression aims to provide summary effects after adjusting for study-level covariates. There are many examples of meta-analysis used without the Protocol-driven approach of systematic reviews, and these are as liable to uncontrolled biases as literature reviews without data analysis.

Robust Evidence-Based Reports

The reports produced by OXSREV, whether systematic reviews or systematic maps, are always driven by a Protocol produced in collaboration with relevant stakeholders. We work with clients to help frame reviewable questions, scope the evidence base,  draw up the Protocol for a systematic evidence evaluation, and conduct the evaluation.

Stakeholder Engagement

During the process of systematic evidence evaluation, different groups will need to be involved.
These groups are not mutually exclusive and will vary between projects. 
In OXSREV we use the Collaboration for Environmental Evidence groupings:

User Group - (e.g. Client, Commissioning organisation) – policy or practice groups that identify the need for evidence and might commission an Evidence Synthesis and/or use its findings in the context of their work.

Review Group – the team that conducts the synthesis and produces the report.

Stakeholder Group – all individuals and organisations that might have an interest (a ‘stake’) in question formulation and the findings of the systematic evidence synthesis.

Protocols & Project Plans

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In systematic evidence evaluation, a Protocol is an independent document that acts as a priori guide and reference to the conduct of
the evaluation that reflects the views of stakeholders.

It is reviewed by people with expertise in the topic under review. Its aim is to minimise bias in the evaluation by setting out clear methodological steps to be followed.

It contributes to the transparency of the evaluation process. The principles of the systematic evaluation Protocol can be adopted during the planning phase for any project to ensure minimum bias and maximum transparency.

Find out more about how OXSREV can help with your protocols and project plans Here

Find out more about our work here at OXSREV or please feel free to get in contact to discuss how we can help with your projects.