Assessing the appropriateness of helicopter emergency medical services for non-traumatic emergencies in a medically underserved rural area, Japan - Shohei Matsubara; Ken-ei Sada; Masataka Kudo; Sho Sasaki; Atsushi Morizane; Koshi Kajihara; Hidenao Okubo; Kosuke Hamagawa; Toshimi Mizobuchi; Toshikazu Yabe; Yuichi Saisaka; Kimiaki Tanaka; et al. (PLoS ONE, 2026)