I agree with Stefan Hardt and colleagues on the benefits of a unified European medical doctorate (Nature 528, 333; 2015). However, removing the research component to create a vocational degree could result in a shortage of clinician scientists.

This is evident from our (unpublished) 2014 survey of 1,069 supervisors of dissertations at Charité in Berlin, one of Europe's largest university hospitals. Just under 1% of 3,714 research projects were of an MD-with-PhD type, more than two-thirds were MD projects and the rest were straight PhDs and dental or nursing projects. Thus, shifting to a purely vocational European medical doctorate system would mean many physicians missing out on useful research training (see also D. M. Milewicz et al. J. Clin. Invest. 125, 3742–3747; 2015).

One solution might be to integrate the European medical doctorate into the medical curriculum. This would also encourage more-consistent application of evidence-based medicine in daily practice throughout the European Union (see J. Hilgers et al. Med. Teach. 29, 270–275; 2007). Formal training of lecturers, tutors and supervisors responsible for this integration would help to standardize and improve the quality of dissertation supervision (see Nature 527, 7; 2015).