Clinicians are routinely required to make decisions about fall risk among lower limb prosthesis users. For these decisions, clinicians should use valid, reliable, quantitative, and multidimensional measures of balance test for individuals with lower-limb amputations. The objective of this study was therefore to establish, validity and reliability for 3 meter backward tests administered to established unilateral lower-limb amputations. This study included a total of 30 lower limb amputees [age (18-65) years]. 3 Meter Backward Walking Test, Rivermead Mobility Index, Timed Up and Go test (TUG) was applied to the patients. The second evaluation (retest) was carried out by the same physiotherapist two days following the first evaluation (test) in order to measure test-retest reliability.

Lower limb amputees (LLA) were recruited from local prosthetic clinics. The inclusion criteria were as follows: unilateral transtibial or transfemoral amputation due to traumatic, dysvascular, or oncologic causes, 18 years of age or older, one or more years of using a prosthesis (i.e., established users), and could walk independently for minimum 10 m). Patients unable to ambulate at least 10 m without an upper extremity assistive device (e.g., cane), have an orthopedic or neurological disease that might influence balance, with complications to their contralateral leg (e.g., joint replacement, arthritis, or wounds), have the severe vision and hearing impairment, amputation of a second limb and individuals with stump wounds and gait problems were not enrolled in the research. This study was conducted as a "test-retest" design and the psychometric properties of the 3-m backward walk test were examined in LLA. The Rivermead Mobility Index, 3-m backward walk test, Berg Balance Scale, Timed Up, and Go test was applied to the patients. An experienced physiotherapist performed all these tests. In order to measure test-retest reliability, the second evaluations (retest) were carried out by the same physiotherapist two days following the first evaluation (test). The same evaluator collected data in order to avoid the inter-rater variability error rate between the evaluations. The patient was evaluated at one time of the day for test and retest.

Participants were asked to walk backward within the 3-meter distance marked with black bands on the floor. Participants were asked to walk backward as soon as possible with the "walk" command, to stop at the end of 3 meters, and the elapsed time was recorded in seconds.

Individuals were allowed to look back if they wanted to. To prevent the individual from falling during walking backward and to support the individual, the physiotherapist who made the evaluation walked with an amputee. Measurements were made 3 times and the average time was recorded. During walking backward, there is a greater feeling of insecurity compared to walking forward and causes fear of falling. Therefore, the therapist stood approximately half a meter behind the patient during the test.

Inclusion Criteria:

• unilateral transtibial or transfemoral amputation due to traumatic, dysvascular, or oncologic causes,
• 18 years of age or older,
• one or more years of using a prosthesis (i.e., established users),
• could walk independently for a minimum of 10 m).

Exclusion Criteria:

• ambulate at least 10 m without an upper extremity assistive device (e.g., cane),
• have an orthopedic or neurological disease that might influence balance,
• with complications to their contralateral leg (e.g., joint replacement, arthritis, or wounds),
• have severe vision and hearing impairment,
• amputation of a second limb and individuals with stump wounds and gait problems