  Background: Evaluation of the quality of research software is a challenging
and relevant issue, still not sufficiently addressed by the scientific
community.
  Methods: Our contribution begins by defining, precisely but widely enough,
the notions of research software and of its authors followed by a study of the
evaluation issues, as the basis for the proposition of a sound assessment
protocol: the CDUR procedure.
  Results: CDUR comprises four steps introduced as follows: Citation, to deal
with correct RS identification, Dissemination, to measure good dissemination
practices, Use, devoted to the evaluation of usability aspects, and Research,
to assess the impact of the scientific work.
  Conclusions: Some conclusions and recommendations are finally included. The
evaluation of research is the keystone to boost the evolution of the Open
Science policies and practices. It is as well our belief that research software
evaluation is a fundamental step to induce better research software practices
and, thus, a step towards more efficient science.
