A Systemic View of Human Error
For decades, human error was often viewed as a simple failure of an individual. However, modern understanding reveals that errors are frequently the result of complex interactions between human cognitive processes and the systems in which they operate. Acknowledging this complexity is the first step toward building safer, more resilient systems in any field, from aviation to healthcare.
Execution Errors (Slips and Lapses)
Execution errors occur when a person's intended action is correct, but the execution of that action goes wrong. These are often linked to distractions, fatigue, or high workload.
1. Capture Slips
This occurs when a more frequent or well-practiced action "captures" or takes the place of a less frequent one. For example, a nurse who always administers a specific medication at 9 a.m. might accidentally give it to a different patient who is in the same bed from a different time shift, due to the automatic routine taking over. The intention was correct, but the habitual action overpowered the conscious decision.
2. Perseveration
Perseveration is the unnecessary repetition of a previous action. An example would be an anesthesiologist mistakenly re-administering a medication because they were distracted and lost track of which steps they had already completed. The repetition is an unintentional failure to recognize that a step was already performed.
3. Omission Errors
This is the failure to perform a necessary step in a sequence. A common example in a clinical setting is forgetting to conduct a final safety check before a procedure, possibly because of an interruption. The intended step is simply left out of the process, often due to distractions or fatigue.
4. Misordering
Misordering errors involve performing the steps of a task in the wrong sequence. For instance, a medical student might correctly identify the necessary steps for a sterile procedure but performs them out of order, compromising the entire process. This can happen under pressure or when memory is taxed.
5. Perceptual Confusion
Perceptual confusion is the misinterpretation of sensory input. This can be as simple as misreading a label due to poor lighting or the label being worn. In a pharmacy, confusing two different medications with similar-sounding names (look-alike, sound-alike drugs) is a classic and dangerous example of this type of slip.
6. Memory Lapses
Memory lapses are a subtype of execution failure where a person simply forgets to do something. This is different from an omission error in that the intention to perform the task is lost from memory. For example, a doctor might forget to update a patient's chart with a new finding immediately after an examination because they were called away by an emergency, and the memory of the task faded.
Planning Errors (Mistakes)
Mistakes happen when the plan or intention itself is flawed, even if the execution is perfect. The error lies in the initial decision-making process.
7. Rule-Based Mistakes (Misapplication)
This type of mistake occurs when an individual incorrectly applies a known, good rule. For example, a paramedic might follow a protocol correctly for a specific condition, but miscategorized the patient's symptoms, leading them to use the wrong rule. The process was followed perfectly, but the initial diagnosis was wrong.
8. Rule-Based Mistakes (Non-compliance)
In this case, a person fails to follow an established rule or procedure. This could be due to shortcuts, overconfidence, or a belief that the rule is unnecessary in a particular situation. An experienced technician might skip a checklist step for a common equipment setup, believing it's a waste of time, which leads to a critical error when a non-standard situation arises.
9. Knowledge-Based Mistakes
These are errors that occur in novel or unfamiliar situations where no clear rules or procedures exist. The individual must use their general knowledge and reasoning to develop a solution. A mistake here results from incomplete or incorrect knowledge. A new healthcare provider, facing a rare patient condition for the first time, might make a diagnostic error due to a lack of specialized knowledge.
10. Communication Errors
While not purely a psychological error, communication failures are a huge contributor to mistakes and slips, especially in complex systems. This involves the breakdown of information exchange between individuals or teams. In a health context, this can be a poorly executed patient handover, where critical information is omitted or misunderstood, leading to a cascade of errors.
Comparison of Error Types
| Feature | Slips & Lapses | Mistakes | Communication Errors |
|---|---|---|---|
| Cause | Execution Failure | Planning Failure | Information Exchange Failure |
| Awareness | Often noticed post-hoc (e.g., "Oops!") | Unaware at the time, only with new information | Often systemic and may not be individual's fault |
| Solution | Focus on process design, environment | Training, knowledge building, debriefing | Structured protocols, tools, safety culture |
| Primary Cognitive Process | Attention, Memory | Reasoning, Knowledge | Communication |
Preventing Human Error
Preventing errors requires a multi-layered approach that addresses both individual human factors and systemic issues. As outlined by resources like the National Institutes of Health, effective prevention strategies involve careful process design, technological support, and robust training.
Here are some key strategies:
- Improve System Design: Redesign processes and equipment to make it easier to do the right thing. For example, using different connectors for different tubing types (a form of 'forcing function') prevents misconnections.
- Standardize Workflows: Create clear, standardized checklists and protocols for critical tasks. Checklists have been proven to reduce errors in surgery and other complex procedures.
- Enhance Training: Provide targeted training that not only covers procedures but also addresses human factors like fatigue management, distraction avoidance, and communication skills.
- Promote a Safety Culture: Foster an environment where individuals feel safe to report errors without fear of punishment. This allows organizations to learn from mistakes rather than simply blame individuals.
- Utilize Technology: Employ technology to automate high-risk tasks and provide safety alerts. Automated dosage calculations and barcoding systems for medication administration are prime examples.
- Debrief and Analyze Errors: Conduct thorough root cause analyses of errors and near-misses. This proactive approach identifies systemic issues rather than focusing on individual blame, as highlighted in this article on medication errors from the National Institutes of Health: Medication errors: definitions and classification.
- Optimize the Environment: Reduce environmental stressors like noise, poor lighting, and frequent interruptions that can contribute to slips and lapses.
Conclusion
Recognizing what are the 10 types of human error is the foundation for creating safer systems and environments. By moving beyond the simple notion of human failure and adopting a systemic perspective, organizations in general health and beyond can implement more effective, evidence-based strategies for prevention. Addressing errors at their source—be it a slip of memory, a flawed rule, or a systemic communication gap—allows for genuine improvement and the protection of both people and processes. A comprehensive approach that combines smart design, continuous learning, and a non-punitive safety culture is the most effective way to manage and mitigate the risks associated with human fallibility.
