According to a recent survey given to surgeons ...

... to assess how they disclosed adverse events to their patients, here are some of the results:

• 92% explained why the event happened
• 87% expressed regret for what happened
• 95% expressed concern for the patient's welfare
• 97% disclosed the event within 24 hours
• 98% discussed steps taken to treat any subsequent problems
• 55% apologized to patients
• 55% discussed whether the event was preventable
• 32% discussed whether recurrences could be prevented

Source: "Surgeons’ Disclosures of Clinical Adverse Events," JAMA Surgery, abstract only, July 20, 2016, http://archsurg.jamanetwork.com/article.aspx?articleid=2534133