The Psychology of Error

1. The Psychology of Error Dr Maria Woloshynowych Imperial College, London META Network - Medication Error research meeting 3-4 March 2004

2. Human error “We all make errors irrespective of how much training and experience we possess or how motivated we are to do it right” From Reducing error and influencing behaviour, HSE. 1999

3. Some myths about errors • Good people do not make mistakes • Errors and mistakes are intentional NB. Often actions, including violations are carried with the best intentions - exceptions • There is always someone to blame • Symmetry between action (cause) and consequence • Illusion of free will – we are in complete control of our actions and situations

5. Error in context The individual • Models and theories of human error The context • Immediate environment • Tasks • Teams • Organisation

6. Types of errors Slips/lapses (execution failures): • Skill based - recognition, attention, memory or selection failure Mistakes (planning or problem-solving failures): • Rule based (e.g. misapplication of a good rule) • Knowledgebased - occur in novel situations, use of inaccurate or incomplete mental models and subject to biases

7. Human performance Physiological factors • Fatigue, sleep, hunger, state of health Emotional factors • Mood states (e.g. anxiety), life events, confidence, motivation, personality Cognitivefactors • Thought processes involved in tasks including cognitive biases Stress: difficult or novel tasks, work load interruptions, urgent tasks, etc.

8. Model of an organisational accident Contributory factors influencing clinical practice Organisational & Corporate Culture Defence Barriers Task Accident / Incident Error Producing Conditions Errors Management Decisions and Organisational Processes Violation Producing Conditions Violations Latent failures in defences Adapted from Reason (1990)

9. Latent failures • Adverse consequences which lay dormant within the system for a long time, only becoming evident when they combine with other factors to break through the system’s defences • These are committed by those far removed in time and space from the immediate area: - designers, high-level decision makers, managers and maintenance personnel. • Decisions are shaped by various factors: - economic, political, practical constraints.

10. Active failures Unsafe acts committed by those at the sharp end (surgeons, physicians anaesthetists, nurses, etc.) These actions can have immediate adverse consequences (e.g. administering the wrong drug, dose, or route) Latent failures Created as a result of decisions taken at the highest levels of the organisation (e.g. staffing levels, choice of equipment) Their damaging consequences become evident when they combine with local trigger factors Differences

11. Framework for the analysis of risk and safety in medicine • Patient factors • Task factors • Individual staff factors • Team Factors • Work environment • Organisation and management • Institutional context Vincent et al., 1998

12. Framework for the analysis of risk and safety in medicine • Patient factors - medical condition, language, personality • Task factors - task design, decision-making aids availability & use of protocols, • Individual (staff) factors - knowledge, skills, health • Team factors - communication, supervision, leadership

13. Framework for the analysis of risk and safety in medicine • Environment - workload, skill mix, equipment • Organisational - financial resources, & managementpolicy, standards, safety culture • Institutional context - NHS executive, regulatory context

14. Person versus System view of error Person Centred View • Focus on the individual, excluding other factors • Individual responsibility and blame - careless, at fault, ‘bad’ • Solution: change behaviour / remove the individual System View • Focus on factors that influence errors • Human beings are fallible, errors to be expected • Solution: change system / conditions of work