An extended protocol for usability validation of medical devices: Research design and reference model

Area of Science:

• Medical device engineering
• Human-computer interaction
• Usability engineering

Background:

• Current medical device usability evaluation methods lack detailed interaction tracing and focus on cross-sectional studies.
• Existing methods often overlook crucial aspects like user learnability and the impact of training.

Purpose of the Study:

• To propose and demonstrate an extended protocol for medical device usability validation testing.
• To address shortcomings in current methods by introducing new measures and study designs.
• To enhance the assessment of medical device usability, learnability, and training effects.

Main Methods:

• Extension of the U.S. Food and Drug Administration's validation testing protocol.
• Introduction of 'normative path deviations' as a novel process measure for quantitative and qualitative analysis.
• Implementation of a longitudinal, within-subject study design to assess learnability and training effects.
• Application of a reference regression model using generalized linear mixed-effects models and Bayesian estimation.

Main Results:

• The extended protocol was implemented in a comparative study of a novel syringe infusion pump prototype against an existing design.
• Significant performance differences were observed between the two syringe pump designs across various usability measures.
• The study revealed varying training-on-the-job effects among healthcare professionals.

Conclusions:

• The extended protocol provides valuable insights into medical device usability, learnability, and training.
• The novel measures and longitudinal design offer enhanced perspectives for validation testing.
• Findings support the refinement of medical device validation testing guidelines for improved safety and efficacy.