Guidelines for Designing and Selecting Accessible Medical Equipment

Molly Follette Story, MS1 , Melissa R. Lemke, MS2 , Christie MacDonald, MPP3 , June Isaacson Kailes, MSW3 , David M. Rempel, MD, MPH4 , Jack M. Winters, PhD2

Rehabilitation Engineering Research Center on Accessible Medical Instrumentation

1 Human Spectrum Design, 2 Marquette University, 3 Western University of Health Sciences, 4University of California, San Francisco

ABSTRACT

The RERC on Accessible Medical Instrumentation (RERC-AMI) has developed accessibility guidelines for the design of medical equipment. The guidelines are based on existing legislation and on the findings from a series of research activities conducted by the RERC-AMI to understand the barriers faced by people with disabilities as patients using medical equipment. Some of the guidelines apply to features that are common across different types of medical equipment, such as patient support surfaces embodied in medical tables and chairs and other platforms. Some of the guidelines apply only to specific types of medical equipment, such as mammography machines and syringe loading devices. The guidelines are intended to be used by medical device designers and manufacturers to produce and healthcare providers to select and purchase accessible medical equipment.

KEYWORDS

Guidelines, standards, accessibility, design

BACKGROUND

The safety, usability, and accessibility of medical equipment play significant, but often overlooked, roles in the quality and delivery of healthcare services to people with disabilities. When healthcare providers are unable to get accurate weights or perform complete examinations because patients cannot use traditional weight scales or get onto diagnostic, therapeutic or procedural equipment, then patients with disabilities may receive substandard health care. Patients may be misdiagnosed because of lack of sufficient assessment or they may lose the benefit of early detection and treatment of diseases. Appropriate access to medical instrumentation can make a difference.

Many people with disabilities do not receive basic healthcare services. A study based on a sample of 77,762 women aged 18 and over from data from the 1994-1995 National Health Interview Survey Supplement on Disability (NHIS-D) found that use of routine physical examinations/checkups varied by severity of disability. The survey revealed that 26.1% of women without functional limitations had received a physical in the past year as compared to 17.2% of women with 3 or more limitations; and 56.2% of women with no functional limitations had never had a routine physical, as compared to 67.8% of women with 3 or more limitations (1).

METHODS

The Rehabilitation Engineering Research Center on Accessible Medical Instrumentation (RERC-AMI, 2002-2007) was focused on medical instrumentation associated with healthcare and employment disparities for people with disabilities. It conducted research studies to identify barriers presented by a wide range of medical equipment and to investigate the most significant problems for the populations most affected. The studies comprised 2 national surveys and 12 regional focus groups, followed by targeted accessibility and usability testing of specific types of medical equipment.

The first survey (n=408) was of people with disabilities from across the U.S. in the role of medical patients (2). The study incorporated an exploratory, cross-sectional design. The survey solicited demographic information and contained questions about 15 broad categories of medical equipment. The second survey was of people with disabilities from across the U.S. in the role of healthcare providers. This study also had an exploratory, cross-sectional design. It recruited a diverse sample of professionals with a wide range of disabilities and medical specialties. The provider survey solicited less demographic information than the patient survey and allowed respondents to select from a list of 15 categories of medical equipment those with which they had professional experience.

Overall, for the patient survey, a majority of the respondents reported having had moderate, extreme, or impossible difficulty with four categories of medical equipment:

Impossible or extremely difficult equipment
Equipment Type n Percent with difficulty
Examination Tables 291 75%
X-ray (Imaging) Equipment 258 68%
Exercise and Rehabilitation Equipment 203 55%
Weight Scales 222 53%

In general, the most prominent concerns in the narrative patient survey data involved: safety issues, positioning and comfort issues, patient transfer issues, issues with visual displays and markings, and issues with activities requiring fine motor movements.

The respondents of the national provider survey (n=92) represented a wide range of medical professions, including physicians, physician’s assistants, nurse practitioners, nurses, occupational therapists, speech therapists, dentists and x-ray technicians. The provider survey results generally confirmed the findings of the patient survey, relative to the types of medical equipment that were problematic and the types of barriers encountered.

Following the two national surveys, the RERC-AMI conducted 12 focus groups in Wisconsin and California to explore, with people with disabilities, some of the most problematic equipment in greater depth and detail. The groups in Wisconsin focused on three topics separately: dental equipment with dental patients and care providers (dentists and dental hygienists); ergometers (exercise bicycles) with elders who used these machines; and medical monitors with people with visual or hearing impairments. The groups in Northern and Southern California focused on 4 categories of equipment with people with disabilities in the role of patients: examination tables, medical chairs, imaging equipment, and weight scales. Two additional California focus groups were conducted, one with elder women and the other with elder men, because these groups were underrepresented in the surveys and other focus groups. These two groups also discussed home health equipment (home monitoring equipment and medication administration equipment)

Following the surveys and focus group sessions, the RERC-AMI conducted accessibility and usability testing of specific types of equipment that were identified as difficult for patients with disabilities to use, including equipment involving positioning tasks (examination tables, weight scales, dental chairs, and hospital beds), radiology equipment (x-ray, CT-scan and fluoroscopy machines), monitoring equipment (infusion pumps and talking blood glucose meters), and medication administration equipment (pill bottles, pill splitters, pill organizer boxes, and syringe loading devices). The testing served to confirm the findings of the previous surveys and focus groups and provided an opportunity for the researchers to observe first-hand use barriers with subjects with various disabilities and obtain subject opinions of the equipment.

To aggregate the findings of these research activities, the RERC-AMI convened a meeting of all key staff and advisors in January 2008. The purpose of the meeting was to review the findings of the RERC-AMI’s research studies and from those findings, develop design recommendations to make medical equipment more accessible for patients with disabilities.

RESULTS

The RERC-AMI team discussed 7 medical equipment categories of which they had generated the most knowledge:

The team prepared a list of the major accessibility barriers and a list of design recommendations specific to each category of equipment. The guidelines are organized by type of equipment so that all needed information is available in one place. The lists overlap to a large degree, as some problems and recommendations are common, but this was deemed desirable because the team believed that the readers would tend to be interested in a single category and would not want to have to access multiple documents to obtain all relevant information.

In addition to specific design guidelines, the RERC-AMI team also posted to its web site general guidelines for Functional Modes for Access. These guidelines were based on existing legislation and associated standards, including Section 508 of the Rehabilitation Act (Section 508) and Section 255 of the Telecommunications Act (Section 255). It also posted guidelines for Design for All, which were based on the Principles of Universal Design (3) and described how they apply to the design of medical equipment. These documents provide a wealth of guidance on how to design accessible medical equipment. Some of the specific guidelines applied to more than one type of equipment, and the team generated a set of recommendations that were repeated among the guidelines for specific devices. One example was Telecommunications and Personalized Interfaces. Another was Patient Support Surfaces (e.g., a table, chair or other platform, such as for imaging). A few of sample guidelines were:

For design guidelines to support patients transferring on and off, the surface should not be too high. Making the surface height-adjustable is generally very helpful but the equipment needs to have a weight capacity that is sufficient to lift most of the patient population while they are on the equipment. The equipment should provide effective handholds to support patients while transitioning on or off. The platform cushion should be wide enough to allow the patient to manuever safely and comfortably into any body position that may be needed or desired (e.g., lie on one side, roll over, shift pressure points). The base of the equipment should not extend past the edge of the support surface or cushion so that wheelchair users can maneuver themselves close alongside, and the base should provide clearance for portable lift equipment. For maintaining specific body positions on the surface, patients need to be offered cushions or pillows to support the involved body parts; straps are helpful for some types of equipment and procedures.

The team also developed recommendations that were specific to single types of equipment. For example:

Patients who use mammography machines while seated in a wheelchair (or chair) need knee clearance below the imaging plate to accommodate their legs and wheelchair footplates. If a patient is required to stand on a weight scale, the scale platform should be large enough to allow patients to assume a wide stance position. The syringe loading device should communicate how much fluid is in the syringe in both visual and audible or tactile formats. It should be easy to position a pill properly in a pill splitter to accurately cut the pill into halves.

DISCUSSION

The accessibility guidelines developed by the RERC-AMI provide criteria for making medical equipment accessible for patients with disabilities. These guidelines build on previous accessibility recommendations, such as those associated with disability legislation (e.g., ADAAG, Section 508, Section 255) and other available documents (e.g., Principles of Universal Design). However, these guidelines interpret those recommendations and apply them specifically to medical equipment. The guidelines cover 7 categories of medical equipment but the process could be extended to other medical devices not sufficiently evaluated during this study.

The process used to develop the RERC-AMI guidelines considered a limited number of categories of medical equipment so not all barriers to healthcare were addressed. Also, the guidelines have not yet received input from the medical device industry and modifications may be needed after that occurs. The process utilized multiple sources of data, including surveys, focus groups and usability testing. It also involved a large number of research staff and advisors who reached consensus reflected in the guidelines.

The RERC-AMI guidelines are posted to their web site (www.rerc-ami.org) and are available for download. They are intended to support medical device designers to develop equipment that is more accessible for patients with disabilities. They may also assist professionals to select and purchase or recommend more accessible medical equipment, whether as procurement officials, healthcare facility administrators, or healthcare providers.

The guidelines are also intended to support the development of voluntary or mandatory standards associated with current legislation, such as the Americans with Disabilities Act (ADA), or future legislation. Some of the recommendations have already been incorporated in the forthcoming AAMI/ANSI HE75 standard, Human Factors Engineering – Design of Medical Devices. In addition, legislation is already pending in Congress. Sen. Tom Harkin (D-Iowa) introduced bills in 2006, S. 1050 and S. 3717, Promoting Wellness for Individuals with Disabilities Act. One section of this bill would require the Access Board to establish standards for accessible medical diagnostic equipment and the RERC-AMI design guidelines should support that effort.

REFERENCES

  1. Chevarley, F.M., Thierry, J.M., Gill, C.J., Ryerson, A.B & Nosek, M.A. (2006). Health, preventive heath care, and health care access among women with disabilities in the 1994-1995 National Health Interview Survey, Supplement on Disability. Women’s Health Issues, 16:297-312.
  2. Winters, J.M.W., Story, M.F., Barnekow, K., Kailes, J,.I., Premo, B., Schwier, E., Danturthi, R.S., & Winters, J.M. (2007). Results of a national survey on accessibility of medical instrumentation. In Winters, J.M. and Story, M.F., eds., Medical Instrumentation: Accessibility and Usability Considerations. Boca Raton, FL: CRC Press, 13-28.
  3. Story, M.F. (2007). Applying the Principles of Universal Design to Medical Devices. In Winters, J.M. & Story, M.F., Eds., Medical Instrumentation: Accessibility and Usability Considerations. Boca Raton, FL: CRC Press.

ACKNOWLEDGMENTS

This work was supported by the National Institute on Disability and Rehabilitation Research, U.S. Department of Education, under grant #H133E020729. The opinions contained in this manuscript are those of the authors and do not necessarily reflect those of the Department of Education.

Contact Information

Molly Follette Story, MS, Human Spectrum Design, 3717 Deauville Place, Santa Rosa, CA 95403, phone (707) 578-6839, email molly@humanspectrumdesign.com