NACSOS-nexus: NLP Assisted Classification, Synthesis and Online Screening with New and EXtended Usage Scenarios
Tim Repke, Max Callaghan
TL;DR
The paper presents NACSOS-nexus, an open-source rearchitecture of the NACSOS platform designed to support scalable, living evidence syntheses. It integrates multi-source data ingestion (including an OpenAlex snapshot), robust deduplication, ML-assisted prioritised screening with statistical stopping criteria, and a flexible, assignment-based annotation workflow. A dedicated query language (NQL), a literature hub, and reusable analytic pipelines enable transparent, reproducible maps and living reviews across research domains. The approach emphasizes data provenance, user-centric annotation management, and an extensible ecosystem for classifier tools and living maps, with broad potential impact on systematic maps and reviews.
Abstract
NACSOS is a web-based platform for curating data used in systematic maps. It contains several (experimental) features that aid the evidence synthesis process from finding and ingesting primary data (mainly scientific publications), basic search and exploration thereof, but mainly the handling of managing the manual and automated annotations. The platform supports prioritised screening algorithms and is the first to fully implement statistical stopping criteria. Annotations by multiple coders can be resolved and customisable quality metrics are computed on-the-fly. In its current state, the annotations are performed on document level. The ecosystem around NACSOS offers packages for accessing the underlying database and practical utility functions that have proven useful in a multitude of projects. Further, it provides the backbone of living maps, review ecosystems, and our public literature hub for sharing high-quality curated corpora.
