Assessing Fitness to Drive

Table of Contents

10.3 Medical standards for licensing

Requirements for unconditional and conditional licences are outlined in the following table for:

  • visual acuity
  • visual fields including monocular vision
  • diplopia.

It is important that health professionals familiarise themselves with both the general information above and the tabulated standards before making an assessment of a person’s fitness to drive.

Medical standards for licensing –Vision and eye disorders
Condition

Private standards

(Drivers of cars, light rigid vehicles or motorcycles unless carrying public passengers or requiring a dangerous goods driver licence – refer to definition)

Commercial standards

(Drivers of heavy vehicles, public passenger vehicles or requiring a dangerous goods driver licence – refer to definition)

Visual acuity

(refer to Figure 15)

Refer to assessment method.

A person is not fit to hold an unconditional licence:

  • if the person’s uncorrected visual acuity in the better eye or with both eyes together is worse than 6/12.

A conditional licence may be considered by the driver licensing authority subject to periodic review if the standard is met with corrective lenses.

Some discretion is allowed in application of the standard by an optometrist/ophthalmologist. However, a driver licence will not be issued when visual acuity in the better eye is worse than 6/24.

A person is not fit to hold an unconditional licence:

  • if the person’s uncorrected visual acuity is worse than 6/9 in the better eye; or
  • if the person’s uncorrected visual acuity is worse than 6/18 in either eye.

A conditional licence may be considered by the driver licensing authority subject to periodic review if the standard is met with corrective lenses.

If the person’s vision is worse than 6/18 in the worse eye, a conditional licence may be considered by the driver licensing authority subject to periodic review, provided the visual acuity in the better eye is 6/9 (with or without corrective lenses) according to the treating optometrist/ophthalmologist. The driver licensing authority take into account:

  • the nature of the driving task;
  • the nature of any underlying disorder; and
  • any other restriction advised by the optometrist or ophthalmologist.

Visual fields (including monocular vision)

Refer to assessment method.

See also text in relation to further considerations for assessing field defects (section 10.2.2).

A person is not fit to hold an unconditional licence:

  • if the binocular visual field does not have a horizontal extent of at least 110 degrees within 10 degrees above and below the horizontal midline; or
  • if there is any significant visual field loss (scotoma) within a central radius of 20 degrees of the foveal fixation or other scotoma likely to impede driving performance; or
  • if there is any significant visual field loss (scotoma) with more than 4 contiguous spots within a 20 degree radius from fixation.

A conditional licence may be considered by the driver licensing authority subject to annual review, taking into account the nature of the driving task and information provided by the treating optometrist or ophthalmologist.

Monocular vision

A person is not fit to hold an unconditional licence:

  • if the person is monocular.

A conditional licence may be considered by the driver licensing authority subject to two-yearly review, taking into account the nature of the driving task and information provided by the treating optometrist or ophthalmologist as to whether the following criteria are met:

  • the visual acuity in the remaining eye is 6/12 or better, with or without correction; and
  • the visual field in the remaining eye has a horizontal extent of at least 110 degrees within 10 degrees above and below the horizontal midline.

A person is not fit to hold an unconditional licence:

  • if the person has any visual field defect.

A conditional licence may be considered by the driver licensing authority subject to annual review, taking into account the nature of the driving task and information provided by the treating optometrist or ophthalmologist as to whether the following criteria are met:

  • the binocular visual field has an extent of at least 140 degrees within 10 degrees above and below the horizontal midline
  • the person has no significant visual field loss (scotoma, hemianopia, quadrantanopia) that is likely to impede driving performance
  • the visual field loss is static and unlikely to progress rapidly.

Monocular vision

A person is not fit to hold an unconditional licence:

  • if the person is monocular.

A conditional licence may be considered by the driver licensing authority subject to two-yearly review, taking into account the nature of the driving task and information provided by the treating ophthalmologist or optometrist, and the comments made in section 10.2.2 under the subheading Monocular vision (one-eyed driver).

Diplopia

A person is not fit to hold an unconditional licence:

  • if the person experiences any diplopia (other than physiological diplopia) when fixating objects within the central 20 degrees of the primary direction of gaze.

A conditional licence may be considered by the driver licensing authority subject to annual review, taking into account the nature of the driving task and information provided by the treating optometrist or ophthalmologist as to whether the following criteria are met:

  • the condition is managed satisfactorily with corrective lenses or an occluder; and
  • the person meets other criteria as per this section, including visual fields.

The following licence condition may apply if corrective lenses or an occluder prevents the occurrence of diplopia.

Corrective lenses or an occluder must be worn while driving. A 3 month non-driving period applies for use of occluders, in order to re- establish depth perception.

A person is not fit to hold an unconditional licence or a conditional licence:

  • if the person experiences any diplopia (other than physiological diplopia) when fixating objects within the central 20 degrees of the primary direction of gaze.

IMPORTANT: The medical standards and management guidelines contained in this chapter should be read in conjunction with the general information contained in Part A of this publication. Practitioners should give consideration to the following:

Licensing responsibility

The responsibility for issuing, renewing, suspending or cancelling, or reinstating a person’s driver licence (including a conditional licence) lies ultimately with the driver licensing authority.

Licensing decisions are based on a full consideration of relevant factors relating to health and driving performance.

Conditional licences

For a conditional licence to be issued, the health professional must provide to the driver licensing authority details of the medical criteria not met, evidence of the medical criteria met, as well as the proposed conditions and monitoring requirements.

The nature of the driving task

The driver licensing authority will take into consideration the nature of the driving task as well as the medical condition, particularly when granting a conditional licence. For example, the licence status of a farmer requiring a commercial vehicle licence for the occasional use of a heavy vehicle may be quite different from that of an interstate multiple combination vehicle driver. The examining health professional should bear this in mind when examining a person and when providing advice to the driver licensing authority.

The presence of other medical conditions

While a person may meet individual disease criteria, concurrent medical conditions may combine to affect fitness to drive, for example, hearing, visual or cognitive impairment (refer to Part A section 2.2.7 Multiple medical conditions and age-related change).

Reporting responsibilities

Patients should be made aware of the effects of their condition on driving and should be advised of their legal obligation to notify the driver licensing authority where driving is likely to be affected. The health professional may themselves advise the driver licensing authority as the situation requires (refer to section 3.3.1 and step 6 of the assessment and reporting process).

References and further reading

  1. Monash University Accident Research Centre. Influence of chronic illness on crash involvement of motor vehicle drivers, 2nd edition, November 2010. Available: http://monashuniversity.mobi/muarc/reports/muarc300.html.
  2. Wood J. Aging, driving and vision. Clinical and Experimental Optometry. 2002; 85: 214–220.
  3. Owsley C, Wood JW, McGwin G. A roadmap for interpreting the literature on vision and driving. Survey of Ophthalmology. 2015; 60; 250–262.

    Visual acuity
  4. Hills BL, Burg A. A reanalysis of California driver vision data: general findings. Crowthorne, Berkshire, Transport and Road Research Laboratories. 1977.

    Visual fields
  5. Clinical methods: the history, physical, and laboratory examinations. In: Walker HK, Hall WD, Hurst JW (eds), 3rd edition. Boston. Butterworths; 1990.
  6. Optometrists Association of Australia. 2012. Clinical guideline: visual field testing. Available: www.optometry.org.au/for-optometrists/guidelines/optometry-australia.aspx.
  7. Imaging and Perimetry Society. 2010, IPS Standards and guidelines.
  8. Schiefer U, Patzhold J, Dannheim F, Artes P, Hart W. Conventional perimetry: Basic terms. Ophthalmologe. 2005; 102(6): 627–646.
  9. International Standards Organization (ISO) standard for perimeters (ISO 12866):1999. Available: http://www.iso.org/iso.
  10. Delaey JJ, Colenbrander A. Visual standards: vision requirements for driving safety with emphasis on individual assessment. Sao Paulo, Brazil. 2006.
  11. Bowers A, Peli E, Elgin J, Mcgwin G, Owsley C. On-road driving with moderate visual field loss. Optometry and Vision Science. 2005; 82: 657–667.
  12. Wood JM, McGwin G Jr, Elgin J, Vaphiades MS, Braswell RA, DeCarlo DK, Kline LB, Meek GC, Searcey K, Owsley C. On-road driving performance by people with hemianopia and quadrantanopia. Investigative Ophthalmology & Visual Science. 2009; 50: 577–585.
  13. McKnight AJ, Shinar D, Hilburn B. The visual and driving performance of monocular and binocular heavy-duty truck drivers. Accident Analysis & Prevention. 1991; 23: 225–237.
  14. Bohensky M, Charlton J, Odell M, Keefe J. Implications of vision testing for older driver licensing. Traffic Injury Prevention. 2008; 9: 304–313.
  15. Wood JM, Lacherez P, Anstey KJ. Not all older adults have insight into their driving abilities: evidence from an on-road assessment and implications for policy. Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 2013; 68: 559–566.
  16. Driver and Vehicle Licensing Agency, United Kingdom. Assessing fitness to drive: guide for medical practitioners. 14 March 2016. Available: https://www.gov.uk/guidance/visual-disorders-assessing-fitness-to-drive.