How long does it take to conduct a systematic review?

Systematic reviews and maps are the ‘gold standards’ in evidence reviews, providing the most reliable evidence for decision-making. However, these methods take a considerable amount of time to do well. The small tasks add up…

Being able to plan the resources needed for a systematic review is crucial for ensuring your review or your grant application is a success.But just how long do they take on average?

PredicTER is a tool for estimating how long a review will take to complete. The tool calculates the time requirements for various tasks involved in reviewing evidence, from planning and coordination to quantitative synthesis and reporting.

The tool contains default values provided by an assessment of 5 years of systematic reviews and maps published by the Collaboration for Environmental Evidence, but users can tailor the tool based on what they know about their own subject.

The Tool

About PredicTER

What is PredicTER?

PredicTER is a decision-support tool for estimating the time requirements of a systematic review or systematic map. The tool was produced as part of a wider project aimed at examining methods used in recent systematic reviews and maps.

How was PredicTER produced?

PredicTER evolved as a means of analysing patterns across recent reviews and is built on an underlying algorithm that combines volumes of evidence and working speeds from ‘average’ CEE reviews and experienced reviewers.

PredicTER is the result of a 4 year project to understand the type and volume of evidence found by researchers conducting CEE reviews. The analysis behind PredicTER involved an assessment of all CEE reviews and maps published between May 2012 and March 2017: 66 systematic reviews and 20 systematic maps. This analysis highlighted the ‘average’ volume of evidence dealt with at each stage of the review process for reviews and maps. These data were supplemented by a survey of 30 researchers with experience of conducting systematic reviews and maps to ascertain time requirements of individual stages.

You can find the data behind PredicTER here: The methods for producing PredicTER and the analysis of the data behind PredicTER’s default values is described in an article published in Conservation Biology here:

Who produced PredicTER?

The PredicTER tool was designed by Neal Haddaway (Stockholm Environment Institute) and Martin Westgate (Australian National University).

Neal is an experienced systematic reviewer, and has conducted a large number of reviews and maps on environmental and development topics. He also helps to develop review methodology, focusing on maximising transparency and efficiency in review processes. Martin is an ecologist and conservation biologist, studying how scientific information can be used to mitigate human impacts on the environment through evidence synthesis and empirical ecology.

Neal and Martin wanted to produce an evidence-based tool to predict the time needed for a systematic review to help with a grant application, and realised that the tool would be incredibly useful to other potential reviewers wanting to understand just how much effort is needed to conduct a review.

Contact us to know more

Contact us if you would like to know more about PredicTER.