Errors in diagnostic radiology

Errors in diagnostic radiology occur for a variety of reasons related to human error, technical factors and system faults.

This classification was proposed by Renfrew et al. in 1992, and at the time of writing (July 2016) remains the most widely accepted classification.

Renfrew et al. proposed the following classification system :

type 1: complacency
- finding identified but attributed to wrong cause
type 2: faulty reasoning
- finding identified as abnormal but attributed to wrong cause
type 3: lack of knowledge
- finding identified but attributed to wrong cause due to lack of knowledge
type 4: under-reading
- missed abnormality that was appreciable in retrospect
type 5: poor communication
- finding identified as abnormal but poor communication to relevant clinician
type 6: technique
- abnormality was not identifiable (even in retrospect) secondary to poor technique
type 7: prior examination
- failure to review previous imaging results in missed finding
type 8: history
- finding missed due to incomplete clinical information
type 9: location
- finding missed because it was outside of region of interest
type 10: satisfaction of search
- failure to find a subsequent abnormality after the initial abnormality was detected
type 11: complication
- most often of interventional procedures
type 12: satisfaction of report
- over-reliance on the prior report

Brook et al. proposed the following classification as an alternative to the Renfrew classification which takes more than human error into account :

latent errors
- 'in-built' system or technical faults that predispose to errors
active failures or human error
- diagnostic errors and misinterpretation
- complications from procedures
- can involve more than one person or be secondary to latent errors
external causes
- beyond the control of the radiologist (e.g. power failures, quenches, etc.)
customer causes
- related to the patient and non-radiology staff (e.g. complying with instructions, unfamiliarity with procedure)