Frequency and outcomes of reduced dose non-vitamin K antagonist anticoagulants: results from ORBIT-AF II (The Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II) - Steinberg, B A; Shrader, P; Pieper, K; Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT; ‐AF) II Investigators (J Am Heart Assoc, 2018)