Premature mortality from all causes and drug poisonings in the USA according to socioeconomic status and rurality: an analysis of death certificate data by county from 2000–15 oleh Meredith S Shiels, PhD, Amy Berrington de González, DPhil, Ana F Best, PhD, Yingxi Chen, PhD, Pavel Chernyavskiy, PhD, Patricia Hartge, ScD, Sahar Q Khan, MS, Eliseo J Pérez-Stable, MD, Erik J Rodriquez, PhD, Susan Spillane, PhD, David A Thomas, PhD, Diana Withrow, PhD, Neal D Freedman, PhD