RESNA 27th International Annual Confence

Technology & Disability: Research, Design, Practice & Policy

June 18 to June 22, 2004
Orlando, Florida

Physical Independence and Mobility: A Study of Functional Performance of Individuals With and Without Service Dogs

Collins DM1,2, Fitzgerald SG1,2, Martin SG1,2,
Furhman SI1,2, Boninger, ML1,3
1Human Engineering Research Laboratories,
VA Pittsburgh Medical Center, Pittsburgh, PA;
2Department of Rehabilitation Science and Technology, University of Pittsburgh, Pittsburgh, PA
3Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA


To examine differences in functional performance, a cross-sectional study compared 145 adults with service dogs to 80 adults without service dogs. The groups differed demographically, as participants with service dogs were significantly older and had lived significantly longer with their disabilities than those not partnered with service dogs. Functional performance was defined as the “Physical Independence” and “Mobility” scores on the Craig Handicap Assessment and Reporting Technique. Though similar in “Physical Independence” scores, participants with service dogs scored significantly higher on “Mobility.” Thus, service dogs may be a viable intervention to improve the mobility of individuals who use wheelchairs.


CHART, mobility, physical independence, service dogs, wheelchairs


Quality of life and fulfillment result from striking a balance between functional demands and having the resources and opportunities available to meet those demands (1). Service dogs are one such resource to assist in meeting the daily functional needs of individuals who use wheelchairs. Service dogs have been reported to decrease reliance of human help and attenuate physical and social obstacles, thus enhancing the quality of life and fulfillment of their partners (2-5).

Changes in functional performance are primary outcome measures of rehabilitation interventions (5-6). Better functional performance permits individuals to live in more independent settings, and reduces the workload of caregivers and paid assistants (7). The tasks with which service dogs are trained to assist include self-care activities, such as dressing, transferring to and from a wheelchair, and mobility. Service dogs also help with household management and community activities as they open doors, pull manual wheelchairs, carry small packages, pay cashiers, and serve as social icebreakers (2-5).

Because functional limitations are significantly correlated to health care utilization, work disability, and socioeconomic status, enhancements in functional performance from partnering with service dogs would be positive indicators for recommending the use of these dogs (6-9). If service dogs do assist their partners as anticipated, they may allow their partners to live in their own homes and to remain in their communities (2,4). Thus, service dogs would improve the quality of life of their partners by being a resource to meet the daily demands of physical independence and mobility.


For individuals who use wheelchairs or scooters, do those partnered with service dogs differ from those not partnered with service dogs in the functional performance areas of “Physical Independence” and “Mobility” as measured by the Craig Handicap Assessment Reporting Technique (CHART)?


A cross-sectional study was conducted of 225 individuals who used wheelchairs or scooters for 80% or more of their daily mobility. One hundred forty-five participants with service dogs comprised the service dog group; 80 participants, without service dogs, comprised the comparison group. These two groups were compared demographically by age, years living with their disabilities, gender, ethnicity, marital status, type of wheelchair used, and type of disability or disabling condition. The functional performance outcomes included the “Physical Independence” and “Mobility” scores of the Craig Handicap Assessment Reporting Technique (CHART). The CHART assesses function, and has been widely used and validated (10). Several domains are included in the CHART: physical independence, mobility, occupation, social integration, and economic self-sufficiency. Higher scores indicate greater independence in the areas being assessed (10).

The service dog group participants were recruited by agencies such as Paws with a Cause® and Canine Companions for Independence. These agencies sent letters describing the study, along with study brochures, to their clients. Comparison group participants were recruited using advertisements placed in newsletters and websites of interest to individuals with disabilities, such as the Muscular Dystrophy Association website, Quest Magazine, and Study brochures were also sent to registry participants of the Human Engineering Research Laboratory, University of Pittsburgh/VA Pittsburgh Healthcare System. Individuals who signed consent forms completed study questionnaires.

An alpha level of 0.05 was established a priori for all analyses. Distributions of the continuous variables were examined, and if skewed, were analyzed with nonparametric statistics. Chi-square or Fisher's exact statistics were used to compare categorical variables. T-tests were used to compare the groups in normally distributed, continuous variables (e.g., age, years living with a disability); Mann Whitney U statistics were employed to compare continuous variables not normally distributed (i.e., “Physical Independence” and “Mobility” scores from the CHART).


Study participants were predominately Caucasian (93.3%) women (74.2%) who used power wheelchairs for mobility (56.0%), were not married (53.3%), and averaged 14.8 years of education. Most of the participants reported having progressive conditions (76%) such as multiple sclerosis, muscular dystrophy, or rheumatoid arthritis. Those with service dogs were significantly older and had lived longer with their disabilities than did those without service dogs (Table 1). Though the groups did not differ in “Physical Independence,” those with service dogs scored significantly higher on “Mobility” than individuals without service dogs (Table 2).

Table 1: Demographic Variables by Dog Ownership and Veteran Status


Comparison Group

Service Dog Group





39.5 ( + 11.6)*

43.3( + 12.8)*

Years with Disability

19.9 ( + 14.6)*

25.1 ( + 15.4)*


56 (70)

111 (76.6)

Use Power Wheelchair

40 (50.6)



71 (88.75)

139 (95.9)


44 (55.0)

61 (42.1)

Years of Education

14.7 ( + 1.9)

15.0 ( + 2.0)

Most Common Disability



* p <0.05


Table 2: Physical Independence and Mobility by Service Dog and Veteran Status



Service Dog




Physical Independence

82.8 ( + 25.6)

87.3 ( + 17.6)


82.9 ( + 19.3)*

88.7 ( + 15.7)*

* p <0.05


Research by Kennedy and LaPlante indicated that as people age they are more likely to require assistance with daily tasks (9). Participants in the service dog group were significantly older and had lived significantly longer with their disabilities than those in the comparison group. As a result, those in the service dog group were expected to have greater functional limitations, and therefore, lower scores in “Physical Independence” and “Mobility” on the CHART. Surprisingly, despite their demographic differences, individuals in the service dog group were similar to the comparison group in “Physical Independence.” Further, individuals partnered with service dogs scored significantly higher on “Mobility” than those in the comparison group. Service dogs may remediate the problems anticipated with older individuals who have lived longer with disabilities.

These findings are positive indicators for recommending service dogs as viable assistance to improve the mobility of individuals who use wheelchairs or scooters. Service dogs may provide assistance for individuals aging with their disabilities.

Further studies should examine the relationship between “Physical Independence” and “Mobility” and the secondary conditions often found with disability—fatigue, pain, and depression. In addition, similar studies should be conducted to increase sample size of groups: males, users of manual wheelchairs, and non-progressive disabilities such as spinal cord injuries, cerebral palsy, or spina bifida.


  1. Granger CV, et al. (1996) Quality and outcome measures for rehabilitation. Physical Medicine and Rehabilitation, R. L. Braddom, ed. p. 240, W. B. Saunders Company.
  2. Lane DR, McNicholas J & Collis GM. (1998) Dogs for the disabled: benefits to recipients and welfare of the dog. Applied animal Behaviour Science 59: 49-60.
  3. Fairman SK & Huebner RA. (2000) Service dogs: a compensatory resource to improve function. Occupational Therapy in Health Care, Vol. 13(2): 41-52.
  4. Allen K & Blascovich J. (1996) The value of service dogs for people with severe ambulatory disabilities. Journal of the American Medical Association, 275(13): 1001-1006.
  5. Camp, MM. (2001) The use of service dogs as an adaptive strategy: a qualitative study, The American Journal of Occupational Therapy , ( 55) 5: 509-517.
  6. Dittmar SS & Gresham GE. (1997) Functional Assessment and Outcome Measure for the Rehabilitation Health Professional. Aspen Publishers, Gaithersburg, MD, p. 233.
  7. Hoenig H, Taylor DH & Sloan FA. (2003) Does assistive technology substitute for personal assistance among the disabled elderly? American Journal of Public Health, 93(2): 330-337.
  8. LaPlante M. (1988) Data on disability from the National Health Interview Survey, 1983-85, NIDRR: Washington, DC.
  9. Kennedy J & LaPlante MP. (1997) A profile of adults needing assistance with activities of daily living, 1991-1992. Disability Statistics Report, 11. U.S. Dept. of Education, National Institute on Disability and Rehabilitation Research: Washington, DC.
  10. Tate D, Forchheimer M, Maynard F, & Dijkers M. (1994) Predicting depression and psychological distress in persons with spinal cord injury based on indicators of handicap. American Journal of Physical Medicine & Rehabilitation. 73(3): 175-183.


Funding for this research was provided by the VA Merit Review Grant D3078R, by VA Stars and Stripes Funding, and the VA JRR&D Pre-doctoral Grant AHRRFP.


Diane M. Collins,
VA Pittsburgh Healthcare System,
Human Engineering Research Laboratories,
7180 Highland Dr., 151R-1,
Pittsburgh, PA 15206;

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