[1] Univ New Brunswick, Fac Nursing, Fredericton, NB E3B 5A3, Canada
[2] Univ Western Ontario, Sch Nursing, London, ON, Canada
[3] Middlesex London Hlth Unit, London, ON, Canada
[4] Johns Hopkins Univ, Sch Nursing, Baltimore, MD USA
[5] Univ Western Ontario, Schulich Sch Med & Dent, London, ON, Canada