“Physician-scientists” are broadly defined as those with MD degrees who devote a substantial part of their professional effort to biomedical research, ranging from basic science, through translational and patient-oriented research (Schafer, 2010). In recent decades, however, the idealized physician-scientist moving effortlessly between the bench, the clinic and the classroom on any typical day (the “triple threat” academic), has been substituted by a modern figure of physician who early in her/his career spends most of the time in primarily clinical practice, then, typically in mid-career, moves to primarily “protected time” for research, to more end in later years spending most of the time in  administrative responsibilities. Careful assessment of such dynamics is critical when developing programs to involve physicians in medical research (Schafer, 2009).
Physician-scientists play a unique and critical role in medical research. Nonetheless, a number of trends followed during the 1980s and 1990s revealed that this career pathway was in serious jeopardy.
Physician-scientists were declining in number and were getting older (Ley and Rosenberg, 2005). Medical school is a crucial entry point into academic medicine and research. One-third of medical students complete medical school without significant exposure to research (Young et al., 2014). This gap in their medical education is significant: research not only exposes medical students to scientific methodology and academic writing, but also encourages them to multitask and critically analyse the scientific literature –
valuable skills that will serve them well in their future medical careers (Solomon SS et al., 2003). Moreover, student participation in research-related activities develops skills in written and oral communication, teamwork, and problem-solving, which are transferable to clinical practice regardless of future research involvement (Yee et al., 2016)
Since the identification of the physician-scientist shortage, institutions have sought to increase student involvement in research through initiatives such as physician-scientist training programs and MD-PhD joint-degree programs, which offer consistent research opportunities throughout medical training and prepare students for dual roles in biomedical research and clinical practice (Yee, 2016). The timing of student exposure to research is critical: most students who participate in research begin their projects in
the first two years of medical school. Hence, it is important to provide mentorship and guidance for research early in preclinical education. (Young et al., 2014)
All over the world, medical-scientist training programmes allow students a unique opportunity to simultaneously intercalate MD and research PhD degrees (the so called ‘MD-PhD joint-degree programs’). 
The nature of these degrees means that the combined programme is arduous, and selection is often restricted to a few highly motivated students. However, graduates of such programmes, clinicianscientists, often go on to obtain substantial research funds and take successful academic and leadership roles. The output of these research programmes has helped to advance medical sciences from the bench to the bedside and maintain rigorously high academic standards in basic and clinical research (Alamri, 2016).