Clinical Informatics Certification Usability & Human-Computer Interaction 2 — Questions and Answers
Question 1: Which usability evaluation method involves observing real users as they complete tasks without interference from the evaluator?
- Expert walkthrough
- Think-aloud protocol (Correct answer)
- Heuristic evaluation
- Cognitive walkthrough
Correct answer: Think-aloud protocol
The think-aloud protocol has users verbalize their thoughts while performing tasks, giving evaluators insight into real user reasoning and pain points.
Question 2: In clinical EHR design, what does the principle of 'error prevention' in Nielsen's heuristics primarily address?
- Providing clear undo functions after errors occur
- Designing the interface to prevent errors before they happen (Correct answer)
- Displaying error messages in plain language
- Offering detailed documentation for troubleshooting
Correct answer: Designing the interface to prevent errors before they happen
Error prevention focuses on designing the interface so problematic situations are impossible or unlikely to occur, rather than just recovering from them.
Question 3: A nurse consistently selects the wrong medication from a dropdown list because similar drug names appear adjacent. Which HCI principle is most violated?
- Flexibility and efficiency of use
- Recognition rather than recall
- Match between system and real world
- Error prevention (Correct answer)
Correct answer: Error prevention
Adjacent similar drug names in a list create high error risk; the interface should be designed to prevent such selection mistakes, violating the error prevention heuristic.
Question 4: What is the primary goal of a 'formative' usability evaluation compared to a 'summative' evaluation?
- To certify the product meets regulatory standards
- To identify and fix usability problems during development (Correct answer)
- To compare two finished products against each other
- To measure user satisfaction after deployment
Correct answer: To identify and fix usability problems during development
Formative evaluations occur during development to find and fix problems iteratively, while summative evaluations assess a finished product.
Question 5: Which cognitive model describes the time it takes a user to point to a target on a screen based on target size and distance?
- Miller's Law
- Fitts's Law (Correct answer)
- Hick's Law
- Norman's Action Cycle
Correct answer: Fitts's Law
Fitts's Law predicts that movement time to a target increases with distance and decreases with target size, informing button placement in clinical interfaces.
Question 6: An EHR system requires clinicians to navigate five menu levels to reach the allergy documentation screen. Which usability principle does this violate most directly?
- Aesthetic and minimalist design
- Visibility of system status
- Flexibility and efficiency of use (Correct answer)
- Consistency and standards
Correct answer: Flexibility and efficiency of use
Deep navigation hierarchies reduce efficiency; the flexibility and efficiency heuristic calls for shortcuts and streamlined workflows for frequent tasks.
Question 7: In the context of clinical decision support alerts, 'alert fatigue' is best addressed through which design strategy?
- Displaying all possible alerts to ensure completeness
- Increasing alert volume to emphasize urgency
- Tiering alerts by clinical significance and reducing non-actionable notifications (Correct answer)
- Requiring two-factor authentication before dismissing alerts
Correct answer: Tiering alerts by clinical significance and reducing non-actionable notifications
Tiering alerts by severity and eliminating low-value notifications reduces override rates and ensures clinicians attend to truly critical alerts.
Clinical Informatics Certification Usability & Human-Computer Interaction 2
Which usability evaluation method involves observing real users as they complete tasks without interference from the evaluator?