SHARING R SCRIPTS TO RE-CODE CANCER REGISTRY DATA FOR INTERNATIONAL RESEARCH

We have prepared a set of R scripts for population-based cancer registries to trans-code their data to a standard format for collaborative research. As an example, we present the experience of disseminating these scripts to facilitate participation in CONCORD-4, for the global surveillance of trends in cancer survival. The CONCORD-4 specification requires separate files for 22 types of cancer in adults (15-99 years) and all cancers in children (0-14 years). Each file contains 54 variables (23 core, 31 optional). Vital status must be ascertained for all cases, even if passive, by computerised linkage or manual verification with the Mortality Information System (SIM). On 9 October 2023, CONCORD-4 was presented to Brazilian registries by webinar. The Belo Horizonte data were linked with SIM to update every patient’s vital status, then the R scripts were used to prepare data files. These were verified as compliant with the CONCORD-4 protocol. The scripts were demonstrated to Brazilian registries on 31 October. The Goiânia and Brasília registries then used the scripts and tutorials to submit data files to CONCORD-4. The scripts have also been adapted to re-code databases created in CanReg-5, in collaboration with the Lampang registry in Thailand. The CONCORD team has described these scripts as “incredibly useful”, and will make them available to registries that use CanReg-5 in other countries, with a users’ manual. This experience demonstrates the use of R, a free software, to prepare registry data for an international study. Script exchange enhances the use of the software.