Safety in numbers: lack of evidence to indicate the number of physicians needed to provide safe acute medical care.

Patient safety in hospital is dependent on a multitude of factors. Recent reports into the failings of healthcare organisations in the UK have highlighted low staffing levels as a significant factor. There is research into the impact of nurse-to-patient ratios on patient safety, but our literature search found little published data that would allow healthcare providers to define a minimum number of physician staff and skills mix that would assure safety in the largest hospital specialty: unscheduled (acute) medicine. Future work should focus on the evaluation of existing data on hospital mortality rates and physician staffing levels as well as on empirical time and motion studies to ascertain the resources required to undertake safe medical care at times of peak demand.