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Published on: February 11, 2014
Occupational psychophysics to establish vision requirements
1Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242-1091, USA. chris-a-johnson@uiowa.edu
Summary
A new method called "occupational psychophysics" quantifies vision requirements for jobs. This systematic approach ensures vision standards are job-related, safe, and consider accommodations.
Area of Science:
- Occupational health
- Vision science
- Human factors engineering
Background:
- Defining vision requirements for occupations is complex.
- Existing methods may not be sufficiently objective or job-specific.
- A standardized, quantitative approach is needed for vocational vision assessments.
Purpose of the Study:
- To develop and implement a comprehensive procedure for determining vision requirements for vocational and occupational tasks.
- To establish a quantitative, systematic method for defining essential job functions related to vision.
Main Methods:
- Conducted evaluations for over 10 state agencies and businesses over 9 years.
- Utilized literature review, job analysis, worker interviews, expert consultation, and simulation studies.
- Assessed visual functions, work environments, and reviewed appeals/incidents.
Main Results:
- Developed occupational simulations to quantitatively assess task performance under various visual conditions.
- Demonstrated changes in task performance and confidence ratings with degraded vision.
- Presented examples for visual acuity, color vision, and binocularity.
Conclusions:
- Introduced "occupational psychophysics" as a quantitative, systematic method for defining job-related vision requirements.
- This approach provides a rational basis for setting vision standards, considering safety and accommodation.
- Facilitates informed decisions on job entry, reasonable accommodation, and work environment adjustments.
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