[1] Northeastern Univ, Sch Nursing, Bouve Coll Hlth Sci, Boston, MA 02115 USA
[2] Univ Toronto, Toronto Gen Hosp, Lawrence S Bloomberg Fac Nursing, Univ Hlth Network,Peter Munk Cardiac Ctr, Toronto, ON M5G 1L7, Canada
[3] Univ Auckland, Sch Nursing, Auckland 1, New Zealand
[4] Univ Penn, Sch Nursing, Ctr Hlth Outcomes & Policy Res, Philadelphia, PA 19104 USA