Table 1

Feasibility, yield, usefulness and reliability per method
Method	Feasibility	Yield	Usefulness	Reliability*

General Practitioners registering events	+/-	+/-	- Different kind of events - Setting areas for improvement per practice in patient safety	-
Pharmacist registering events	+	-	- Only medication errors - Guidance in improving patient safety in prescribing medication	-
Patients' questionnaire about patient safety	++	+	- Different kind of events - Revealing GPs' blind spots - Setting areas for improvement per practice in patient safety	+/-
Random audit of medical records	+/-	+	- Mostly therapeutic and communication events - Time consuming	+
Audit of medical records of deceased patients	+	+/-	- Different kind of events - Low number of patients	-

*Is this measure a reliable estimate for the actual number of events in general practice
Wetzels et al. BMC Family Practice 2008 9:35 doi:10.1186/1471-2296-9-35