In 2004, the Canadian Adverse Events Study found that adverse events occurred in more than 7% of hospital admissions, and estimated that 9,000 to 24,000 Canadians die annually after an avoidable medical error.
2004年，加拿大不良事件研究（英文：Canadian Adverse Events Study）項目發現，在超過7%的醫院住院治療過程中發生過不良事件，並估計每年有9,000～24,000名加拿大人死於可以避免的醫療差錯。