Herold R (2026). ctrdata: Retrieve and Analyze Clinical Trials Data from Public Registers. doi:10.32614/CRAN.package.ctrdata, R package version 1.26.1, https://CRAN.R-project.org/package=ctrdata.

Herold R (2025). “Aggregating and analysing clinical trials data from multiple public registers using R package ctrdata.” Research Synthesis Methods, 1–33. doi:10.1017/rsm.2025.10061.

Corresponding BibTeX entries:

  @Manual{,
    title = {ctrdata: Retrieve and Analyze Clinical Trials Data from
      Public Registers},
    author = {Ralf Herold},
    year = {2026},
    note = {R package version 1.26.1},
    url = {https://CRAN.R-project.org/package=ctrdata},
    doi = {10.32614/CRAN.package.ctrdata},
  }

  @Article{,
    title = {Aggregating and analysing clinical trials data from
      multiple public registers using R package ctrdata},
    doi = {10.1017/rsm.2025.10061},
    journal = {Research Synthesis Methods},
    author = {Ralf Herold},
    year = {2025},
    pages = {1–33},
  }