Barriers to enrollment in a randomized controlled trial of hydrocortisone for cardiovascular insufficiency in term and late preterm newborn infants. - Watterberg KL; Fernandez E; Walsh MC; Truog WE; Stoll BJ; Sokol GM; Kennedy KA; Fraga MV; Beauman SS; Carper B; Das A; Duncan AF; et al. (Journal of perinatology : official journal of the California Perinatal Association, 2017)