The number of victims of human trafficking has been selected as an indicator to measure progress towards the implementation of SDG target 16.2. In light of current efforts and challenges to collect this type of information, this research brief explores the potential of Multiple Systems Estimation as an alternative, efficient method of estimating the number of non-detected numbers of victims of trafficking in persons in a country.

In short, the MSE methodology utilizes existing lists of victims of trafficking by different authorities or NGOs and on the basis of a statistical methodology based on the concept of the caprture-ricaprture method the “dark figure” of victims that are not included on any list is estimated by analyzing the overlaps between the lists.

An analysis of the data on identified victims of countries in the UNODC database on trafficking in persons of 2012 suggests that MSE could potentially be applied to existing databases of around fifty countries around the world. This research brief provides some recommendations on the next steps in the design of an efficient international statistical system on detected and undetected victims of human trafficking as envisaged by the SDG indicator framework.