The acronym is ROAD (no S) and it's a several decade old acronym for the four specialties which at the time provided a healthy balance of competitiveness, salary and light workload. Those specialties were radiology, ophthalmology, anesthesiology, and dermatology. It should be noted that anesthesiology has had an up and down history in terms of competitiveness and is now not as unattainable as the other fields, rad onc has since become a separate specialty from radiology and probably offers comparable competitiveness, salary and hours, and many pundits would suggest that thanks to shift work, EM now offers better hours for the buck than many of the more competitive field. But the ROAD acronym persists in the medical vernacular.