Frugal and reverse innovations in emergency medicine: a concepts piece.

We suggest that low-cost innovations, termed as frugal, when diffused from low-income and middle-income countries to high-income countries, offer an opportunity to diversify sources of ideas and solutions in emergency medicine. We outline examples from a preliminary search of the literature, consider the barriers faced by such innovations and suggest what needs to be done to improve their chances of being considered for use in emergency medicine.