Bellwether Procedures for Monitoring Subnational Variation of All-cause Perioperative Mortality in Brazil - Truche, Paul; Roa, Lina; Citron, Isabelle; Caddell, Luke; Neto, Joao; Reis, Matheus; Moore, Eileen; Botelho, Fabio; Alonso, Nivaldo; Watters, David (World journal of surgery, 2020)