Use of standardized outcome measures for people with lower limb amputation: A survey of prosthetic practitioners in the United States

Abstract

Objective:

To assess the clinical resources available for the assessment of health outcomes in people with lower limb amputation, and to understand barriers and facilitators associated with use of standardized outcome measures in clinical practice.

Design:

Cross-sectional survey.

Setting:

General community (online).

Participants:

A volunteer sample of prosthetic clinicians was recruited through national professional organizations. Eligible participants were clinicians certified by a professional prosthetics organization and currently practicing as a prosthetist, prosthetist-orthotist, or prosthetic assistant.

Interventions:

Not applicable.

Main Outcome Measure:

A custom-designed online survey on clinical use of patient-reported and performance-based standardized outcome measures to assess patients with lower limb amputation.

Results:

A total of 375 participants completed the survey. Most participants (79%) reported that they are encouraged or required to administer standardized outcome measures in their clinic or facility. Most participants reported that use of patient-reported and performance-based outcome measures are within their scope of practice (88%) and that they have the knowledge required for outcomes measurement (84%). Few participants agreed that outcomes measurement is standardized across the profession (30%). Most participants had access to small spaces and equipment for outcomes measurement, such as short hallways (65–94%), stairs (69%), and tablets with wireless internet connection (83%). Most participants reported that they would be willing to spend between 5 (36%) and 10 (43%) minutes on self-reported surveys, and between 10 (41%) and 20 (28%) minutes on performance-based tests.

Conclusions:

Outcomes measurement is encouraged or expected in contemporary prosthetic practice. Strategies to improve standardization and efficiency of administration are needed to facilitate routine use of outcome measures in clinical care.

Routine and standardized measurement of clinical outcomes is increasingly recognized as a critical component of evidence-based practice across medical professions, including prosthetics.(1–3) Collection and documentation of outcomes helps practitioners evaluate a patient’s current health status, track changes in patient health status over time, and make informed clinical decisions about treatment options.(4,5) The assessment of mobility (ie, the ability to move from one place to another(6)) is particularly important in rehabilitation for people with lower limb amputation, given that a main objective of a lower limb prosthesis is to restore ambulatory mobility. To this end, several standardized patient-reported and performance-based measures of mobility have been developed for(7–9) or tested in(10–14) people with lower limb amputation.

Due to the importance of outcomes measurement in prosthetics practice, studies have been conducted over the last decade to understand prosthetists’ experiences and attitudes with regards to using standardized outcome measures.(15–17) Similar studies have been conducted in other rehabilitation professions.(18–22) The proportions of prosthetic providers that reported routine outcomes measurement ranged from 38%(15) to 69%(17), which may reflect evolving trends in recent years. Results also suggested that prosthetic practitioners who routinely used outcome measures perceived them to be beneficial(16,17). Practitioners generally reported few barriers to using outcome measures,(16,17) but of those identified, the most common were related to difficulty integrating measurement into clinical routines(16), the time required for measurement,(17) and challenges choosing appropriate outcome measures.(17) These studies also demonstrated that outcomes measurement training can improve provider confidence in performance-based test administration in both the short(15) and long term(16). While these studies have provided valuable information, they may not reflect current practices due to the rapidly evolving state of outcomes measurement in the prosthetics profession.

A recent interview study(23) built upon prior work by asking prosthetists, physical therapists, and physiatrists engaged in prosthetic patient care about the resources (eg, time, space, equipment) available to facilitate use of performance-based and patient-reported outcome measures. Participants in this study reported access to small-to-medium spaces, basic measurement equipment, and sufficient training to administer some mobility tests in their clinics. Many participants also reported limitations in the time they were willing to spend compared to the time needed to administer several standardized outcome measures. However, as these results were derived from a small number of practitioners from each discipline (eg, eight prosthetists), data from a larger sample is needed to characterize the prosthetics profession more accurately.

Therefore, the purpose of this study was to assess the current state of outcomes measurement in a large sample of prosthetics practitioners, including professional expectations, practice habits, barriers and facilitators, and general opinions about the value of outcomes measurement. Practitioners were also surveyed about the time, space, and equipment resources they have for administering standardized outcome measures and their comfort with select self-report surveys and performance-based tests.

Methods

A cross-sectional, observational survey study was conducted between July 2020 and April 2021 with prosthetists and prosthetic assistants across the United States. The study protocol was reviewed and determined to qualify for exempt status by an Institutional Review Board.

Participants

A voluntary sample was recruited through mailing lists for the American Board of Certification in Orthotics, Prosthetics, and Pedorthics (ABC) and the Board of Certification/Accreditation (BOC). Information about the study was also posted to the Orthotic and Prosthetic Listserv (University of Florida, Gainesville, USA) and emailed to professional contacts. Participants were required to meet the following eligibility criteria: 18 years of age or older, prosthetic certification, and currently practicing as a prosthetist or prosthetic assistant.

Sample size justification

A sample of 355 participants was targeted for this study. The sample size target was calculated based on the total number of ABC- and BOC- certified prosthetists and prosthetist assistants (N=4,525), a 95% confidence level, and a 5% margin of error.(4,24,25)

Survey

A custom survey (Supplement 1) was developed based on existing literature(15–22) and preliminary interviews with prosthetists, physical therapists, and physiatrists.(23) The survey focused on clinical use of outcome measures (ie, self-report surveys and performance-based tests) intended to assess people with lower limb amputation. Participants were asked about the reasons they administered outcome measures, how often they administer outcome measures for different purposes, their comfort administering specific outcome measures (presented in alphabetical order), and their opinions about outcomes measurement. Participants were also asked about clinical expectations for measurement, time allotted for clinical activities, and space and equipment available to administer performance-based tests. Space footprints and equipment included in the survey were based on those required for a variety of performance-based tests suited to prosthetic clinical care. Professional and demographic characteristics were collected to characterize the study sample.

Survey instructions and questions were pilot tested with a convenience sample (n=4) of prosthetists who practiced in a variety of clinical settings. Pilot test participants first completed the electronic survey (average time to complete the test survey was 27 (SD 5) minutes). They then participated in a cognitive interview, where they commented on the length, content, and relevance of the survey. Based on feedback in cognitive interviews, the final survey was shortened to reduce administration time, and the instructions and several questions were modified to improve clarity.

Study Procedures

The final survey was built using Research Electronic Data Capture (REDCap, Vanderbilt University, Nashville, USA) (26,27) hosted at the University of Washington. A link to the online survey was distributed to potential participants via postcards (2050 postcards were sent), emails (598 emails were sent), and listserv postings. A reminder was sent to non-respondents 3–4 weeks after the initial invitation. Eligibility was self-assessed via screening questions. Respondent names were collected to ensure that each response was from a unique participant and cross-checked with ABC and BOC databases to verify eligibility. Survey responses were reviewed for missing and/or inconsistent data, and participants were contacted to collect missing data or clarify responses as needed. Suspect responses and incomplete surveys were excluded from analyses based on consensus of two authors (B.H. and S.M.).

Analysis

Descriptive statistics were calculated to characterize the sample and survey responses. Frequencies and percentages were calculated for categorical data. Numerical data were visually analyzed with quartile-quartile plots and assessed for normality using the Shapiro-Wilk test. Means and standard deviations were calculated for numerical data that were normally distributed; medians and ranges were calculated for numerical data that were not. Frequency of outcome measure use was grouped to facilitate data interpretation: responses of “often” and “always” were grouped as “routine” use, “rarely” and “sometimes” were grouped as “occasional” use.(15,16)

To assess representativeness of the sample with respect to the population of certified prosthetic practitioners in the US, we compared sample characteristics to those reported by ABC in their 2015 Practice Analysis(28) using Chi-squared tests for the following characteristics: gender, age groups, race/ethnicity, education level, and years of clinical experience. Statistical analyses were performed with SPSS 19 (IBM, Armonk, NY); a threshold of α=0.05 was applied to assess significant differences.

Results

Participants

Of the 509 total survey responses, 134 were excluded from the final dataset (56 were incomplete, 31 could not be verified via the ABC or BOC directories, 27 were duplicate responses, 8 were practicing outside of the United States, 8 were not a prosthetist or prosthetist assistant, and 4 were deemed problematic by investigators due to irregular or inconsistent responses). A total of 375 were complete and included in the final dataset (Tables 1–2). The average time to complete the survey was 22 (SD 10) minutes. Nearly all participants were certified prosthetists (99%) and a majority were male (64%). The sample median age was 39.3 years (range 25–76 years) and the median reported years in practice was 12.0 (range 1–52 years). Approximately half of the sample (52%) reported their highest education level to be an associates or bachelor’s degree, and 48% had attained a master’s degree or higher. Only 42% had formal college or university coursework specific to outcomes measurement. The sample largely comprised of practitioners employed in private clinics (83%). Compared to the ABC practice analysis sample (Table 1), the study sample was significantly younger (χ²(5)=46.8, p<0.001), reported fewer years of practice experience (χ²=34.5, p<0.001), and had a higher percentage of female participants (χ²(2)=30.4, p<0.001) and participants with master’s degrees (χ²(4)=118.0, p<0.001). No differences were found between the samples based on race/ethnicity.

Table 1.

Demographics of the study sample (n=375), compared to the sample described in the 2015 ABC Practice Analysis (n=601).(27)

Characteristic	Present study sample (2021)		ABC Practice Analysis sample (2015)		p
	n	%	n	%
Age group					<.001
25–34	131	35%	120	20%
35–44 years	104	28%	138	23%
45–54 years	74	20%	156	26%
55–64 years	43	11%	144	24%
65 years and older	17	5%	24	4%
Unknown	6	2%	18	3%
Gender					<.001
Male	241	64%	475	79%
Female	125	33%	108	18%
Prefer not to answer or not reported	9	2%	18	3%
Race/ethnicity					.15
Alaskan native or American Indian	2	1%	7	1%
Asian	16	4%	20	3%
Black or African American	2	1%	7	1%
Hispanic or Latino	9	2%	19	3%
White	305	81%	505	84%
Multiracial	9	2%	4	1%
Other/unknown	30	8%	38	6%
Education level					<.001
High school or GED	2	0.5%	36	6%
Associate’s degree or professional certificate	26	7%	48	8%
Bachelor’s degree	170	45%	409	69%
Master’s degree	167	45%	90	15%
Advanced degree (eg, clinical doctorate, PhD)	10	3%	6	1%
Time in prosthetics practice					<.001
Up to 5 years	101	27%	96	16%
6–10 years	72	19%	90	15%
11–20 years	97	26%	144	24%
21–30 years	58	16%	156	26%
31 years or longer	46	12%	114	19%

Table 2.

Professional characteristics of the study sample.

Characteristic	n	%
Professional designation (>1 answer allowed)
Prosthetist or prosthetist-orthotist	371	99%
Prosthetic or prosthetic-orthotic assistant	4	1%
Employer
Private clinic with a single facility	55	15%
Private clinic with 2–10 facilities	123	33%
Private clinic with more than 10 facilities	132	35%
Private, state, county, or University hospital	28	7%
VA or Military hospital	15	4%
Children’s hospital	12	3%
Other or not reported	10	3%
Practice location
Midwest	90	24%
Pacific	87	23%
Southeast	87	23%
Northeast	44	12%
Southwest	43	11%
Rocky Mountains	19	5%
Not reported	4	1%
Noncontiguous US	1	0.3%
Patient characterization
See primarily adults with lower limb amputation (LLA)	329	88%
See primarily children with LLA	15	4%
Even distribution of children and adults with LLA	18	5%
Do not see patients with LLA	12	3%
Percent of patients with LLA in prior year (of entire patient load)
>75%	112	30%
50–75%	39	10%
25–50%	89	24%
5–25%	90	24%
<5%	40	11%
Have not seen patients with LLA in the last year	5	1%

Use of outcome measures in clinical practice

Most participants (79%) reported that standardized outcome measures are encouraged or required at their clinic or facility. The large majority (93%) of participants reported use of self-reported surveys and/or performance-based tests with their patients. Slightly more participants indicated they used self-reported surveys (87%) than performance-based tests (84%). Most participants (75%) reported administering outcome measures themselves, however more reported personally administering performance-based tests (70%) than self-report surveys (51%). Far fewer participants relied only on others (eg, an assistant, front office staff) to administer outcome measures (18%) or did not use outcome measures at all (7%).

The most-endorsed reasons for routinely using self-report surveys (Figure 1) were “to evaluate patient progress” (41%), “to justify service to payers” (39%), “to communicate with patients” (34%), and “for practice management purposes (eg, quality improvement)” (33%), whereas the most-endorsed reasons for routine use of performance-based tests (Figure 2) were “to justify service to payers” (48%), “to inform clinical decisions” (45%), and “to evaluate patient progress” (43%). The least-endorsed reasons for using surveys and tests were similar, and included “for research purposes” (self-report surveys: 16%; performance-based tests: 12%) and “for facility or provider accreditation” (self-report surveys: 23%; performance-based tests: 19%).

Figure 1.

Percent of study participants who reported using self-report surveys for the listed reasons.

Figure 2.

Percent of study participants who reported using performance-based tests for the listed reasons.

Comfort with standardized outcome measures

The Prosthetic Limb User’s Survey of Mobility (PLUS-M)(7) was the self-report survey participants felt most comfortable using, with 60% of participants indicating that they were “comfortable” or “very comfortable” administering and interpreting scores of this measure (Figure 3). Approximately half of the sample indicated also being comfortable with the Prosthetic Evaluation Questionnaire (PEQ)(9) (56%) and the Activities-specific Balance Confidence Scale (ABC)(29) (48%). The self-report surveys with which participants reported being least comfortable were the Houghton Questionnaire(30) (14%), the Trinity Amputation and Prosthesis Experience Scales (TAPES)(31) (14%), and the Locomotor Capabilities Index (LCI)(32) (15%).

Figure 3.

Percent of study participants who reported comfort with administering select self-report surveys. Abbreviations in the figure: PLUS-M, Prosthetic Limb Users Survey of Mobility; PEQ, Prosthetic Evaluation Questionnaire; ABC, Activities-specific Balance Confidence Scale; OPUS, Orthotic and Prosthetic Users Survey; LEFS, Lower Extremity Functional Scale; PSFS, Patient Specific Functional Scale; LCI, Locomotor Capabilities Index; Houghton, Houghton Questionnaire.

Of the performance-based tests (Figure 4), participants indicated that they were most comfortable administering the Amputee Mobility Predictor (AMP),(8) Timed Up and Go (TUG),(33) and Two-minute Walk Test (2MWT),(34) with 77%, 76%, and 71% of participants indicating that they were “comfortable” or “very comfortable” with these tests, respectively. As a group, participants were least comfortable with the Comprehensive High-level Activity Mobility Predictor (CHAMP)(35) as only 12% of respondents indicated any level of comfort administering this test.

Figure 4.

Percent of study participants who reported comfort with administering select performance-based tests. Abbreviations in the figure: AMP, Amputee Mobility Predictor; TUG, Timed Up and Go; 2MWT, 2-Meter Walk Test; 10mWT, 10-Meter Walk Test; 6MWT, 6-Minute Walk Test; 5xSTS, Five Times Sit-to-Stand; FSST, Four Square Step Test; BBS, Berg Balance Scale; L-Test, L-Test of Functional Mobility; FRT, Functional Reach Test; CHAMP, Comprehensive High-level Activity Mobility Predictor.

Perceptions of outcome measures

Most participants agreed or strongly agreed that self-report surveys (Figure 5) “are within my scope of practice” (88%), “can be administered with knowledge that I have” (85%), and “are inexpensive” (83%). Alternatively, few participants agreed that self-report surveys “are helpful in acquiring insurance approvals” (37%) or “are administered in a standardized way throughout my profession” (30%).

Figure 5.

Percent of study participants who agreed with the listed statements about use of self-report surveys in prosthetics practice.

Regarding performance-based tests (Figure 6), participants generally agreed or strongly agreed that tests “are within my scope of practice” (87%), “can be administered with knowledge that I have” (84%), and “are inexpensive” (76%). Few agreed that performance-based tests “are administered in a standardized way throughout my profession” (30%) or “can be quickly administered” (28%).

Figure 6.

Percent of study participants who agreed with the listed statements about use of performance-based tests in prosthetics practice.

Clinical resources available for administering outcome measures

Most participants reported having access to a 3.5m (94%) or a 9m (65%) hallway for administration of performance-based tests, but less than a third (31%) had access to a 12m hallway (Table 3). Few participants (7%) reported having access to a 14m × 14m open space or gymnasium that could be used for administering performance-based tests, like the CHAMP, that required larger spaces. Participants who worked hospital settings generally had more access to spaces for performance-based testing than those who worked in private practice settings. Participants also generally indicated they had access to equipment required to administer self-report surveys and performance tests (Table 3). Most participants (83%) reported access to a tablet with wireless internet and some type of stairs (69%). Few participants (16%) reported access to a treadmill in their clinic.

Table 3.

Space and equipment available to survey participants for administering outcome measures.

Space, settings, and equipment	n	%
Walking and running
Space where a patient could walk 5 m and turn around	350	93%
Space where a patient could walk 10 m and turn around	258	69%
Space where a patient could walk 30m and turn around	76	20%
Space where a patient could run or jog	178	47%
Outdoor space where a patient could walk over uneven surfaces	324	86%
A treadmill	61	16%
A gym/large indoor space	53	14%
Spaces by dimensions
3.5m hallway	353	94%
9m hallway	243	65%
12m hallway	117	31%
3m × 3m room	177	47%
8m × 3m space	167	45%
16m × 3m space	41	11%
9m + 5m ‘L’ shaped	156	42%
14m × 14m gym	24	6%
Stairs and ramps
Any number of stairs	258	69%
A set of therapy stairs with 3–5 steps	164	44%
A staircase with 6–8 steps	138	37%
A staircase with 9 or more steps	114	30%
A low-grade (up to 5 degrees) ramp without a handrail	210	56%
A low-grade (up to 5 degrees) ramp with handrail	126	34%
Data collection devices
A tablet with wireless internet access	312	83%

Time available for administering outcome measures

The median time of clinical appointments was reported to be 60 minutes (range 10–180) for an evaluation and 45 minutes (range 0–180) for a follow-up appointment. In general, participants were willing to spend more time administering performance-based tests and self-report surveys during evaluation appointments than in follow-up appointments (Figure 7). Most participants reported that the maximum time they would spend administering self-reported surveys during an evaluation appointment was either 5 minutes (36%) or 10 minutes (43%). For performance-based tests, most participants reported the maximum time they would be willing to spend was 10 minutes (41%) or 20 minutes (28%). Approximately half of participants indicated they would spend no more than five minutes communicating results of standardized outcome measures to patients (49%) or documenting results (49%) during an evaluation appointment.

Figure 7.

Time that study participants were willing to spend administering, communicating, and documenting outcome measures during evaluation and follow-up appointments.

Discussion

This study assessed the current state of standardized outcomes measurement in prosthetic clinical practice. Approximately 80% of prosthetic providers in this study reported that they are encouraged or required to use outcome measures in the clinic, and less than 10% of providers reported that they do not use standardized outcome measures at all. Similar to prior studies,(16,17) most prosthetists agreed that outcomes measurement is within their scope of practice and indicated that they felt comfortable administering a number of standardized outcome measures. Together, these results suggest that modern prosthetics practice increasingly includes a growing and maturing culture of outcomes measurement.

Although outcomes measurement is increasingly expected of prosthetic practitioners, day-to-day integration of measurement into clinical practice may still be challenging. Many prosthetics practitioners in the present study reported constraints to time and space that hinder routine administration of common self-report surveys or performance-based tests. For example, most practitioners noted that they would be able to allocate no more than 10 minutes for outcome measure administration during an evaluation appointment, and even less time during subsequent follow-up appointments. Most practitioners also noted that, while they had access to short hallways and small clinic rooms for outcomes administration, they did not have access to longer hallways and gyms. Unlike other rehabilitation specialists (eg, physical therapists), prosthetic clinics most often consist of small, private clinical rooms rather than larger, open rehabilitation areas.

The time, space, and equipment constraints described by prosthetic practitioners can be used to assess the feasibility of administering specific standardized outcome measures in routine clinical care. The resources available to practitioners in the current study are generally appropriate for administering the self-report surveys with which participants reported being comfortable (eg, PEQ, ABC, PLUS-M). Wide-spread access to tablets with wireless internet can also facilitate efficient administration, scoring, and interpretation of standardized self-report surveys. In addition, most practitioners in the current study would have the resources available to administer brief performance-based tests, like the TUG. However, few would have the resources to administer other mobility performance tests that are well-suited to the assessment of people with lower limb amputation (Table 4). For example, even though many prosthetic providers reported comfort with administering performance-based tests like the AMP and 2MWT, most participants did not have adequate time to administer the AMP or space to administer the 2MWT. These findings are similar to those described in a prior interview study(23) with a multidisciplinary group of rehabilitation practitioners. Overall, the time clinicians are willing to spend on outcomes measurement and the space available in many prosthetics clinics reinforce the need for measures designed specifically with these limitations in mind. These constraints are especially pertinent to performance-based tests, which often take more time and require larger spaces to administer than self-reported surveys. The overall lack of time and space reported by participants may ultimately lead to use of select tests (ie, those that fit the available space) or less routine use of many performance-based tests in general.

Table 4.

Survey participants who reported the time and space required for mobility performance tests commonly administered to people with lower limb amputation.

Measure	Brief Description	Required resources*		Participants with available resources		Primary limiting resource
		Time	Space	n	%
TUG	Time (s) to stand up, walk 3 m, return to the chair, and sit down.	<5 min	4 m × 1.5 m room/hallway	357	95%	N/A
L-test	Time (s) required to stand up, walk 10 m in an “L’ shape, return to the chair, and sit down.	<5 min	4 m × 8 m room or room + hallway	154	41%	Space
10mWT	Time (s) or speed (m/s) required to walk a distance of 10 m.	<5 min	11 m hallway	259	69%	Space
2MWT	Distance (m) covered in 2 min of walking back and forth in a corridor	<5 min	31 m × 1.5 m room/hallway**	74	20%	Space
6MWT	Distance (m) covered in 6 min of walking back and forth in a corridor	<10 min	31 m × 1.5 m room/hallway†	68	18%	Space
AMP	Score based on observed ability to complete a series of low-to-mid-level mobility tasks.	<15 min	5 m × 1.5 m room/hallway, stairs	109	29%	Time
CHAMP	Score based on observed ability to complete a series of high-level mobility tasks.	<15 min	12 m × 12 m room/gym	12	3%	Space

^*Required resources were based on information provided in the development article or published instructions. In cases where resources were not described in sufficient detail, the investigators came to consensus on the equipment, time, and space required to administer all tasks in the test.

Limitations in time and space resources may also contribute to variations in measure administration within or across clinical facilities. Less than 30% of the practitioners in the current study agreed that outcome measures were administered consistently across the prosthetics profession. Inadequate standardization is problematic because measured differences in scores may be attributed to variable methods of administration, rather than true changes in performance. For example, a recent study that compared 2MWT scores for people with lower limb amputation that were collected in research and clinical settings. Study investigators demonstrated that 2MWT scores (ie, distance walked in two minutes) significantly differed due to variations in test administration protocol between settings.(36) Variations in administration protocol may result in low-quality data and diminish some of the benefits of using outcome measures, particularly if the clinician wanted to compare patient data to population-based norms or contribute to multi-clinic studies or registries. Future work using consensus research methods (eg, Delphi studies(37)) could address the perceived lack of measurement standardization across the profession and better align practitioners and researchers on which outcomes to measure and the methods by which those outcomes should be measured. Consensus on outcomes measurement across the prosthetics profession is especially important as the Limb Loss and Preservation Registry (LLPR) begins to collect data on patient outcomes.(38) The LLPR will gather clinical evidence from hospitals and prosthetic clinics throughout the U.S. to inform treatment decisions in prosthetics care. It is therefore the responsibility of the prosthetics profession to ensure that outcome measures are being administered and scored consistently across practitioners and clinics so that these data can be effectively aggregated.

Most practitioners in the present study reported at least occasional use of both self-report and performance-based outcome measures for a variety of reasons. However, fewer than half of all participants reported using self-reported surveys or performance-based tests routinely for any of the purposes listed in the survey. Notably, most participants did not routinely use outcome measures for clinical purposes, such as measuring patient progress, informing clinical decisions, communicating with patients, or evaluating the effectiveness of treatments. Using outcome measures only occasionally for these purposes may diminish the value of these instruments to both the practitioner and patient. Finding ways to facilitate more routine use of outcome measures for such purposes should be viewed as an opportunity for the profession, and may require innovative methods or technologies to facilitate data entry, scoring and interpretation, visualization of trends over time, and integration with medical record systems. Such innovations are needed to promote efficient measurement of patient outcomes and effective communication of findings to patients, particularly given the time constraints of typical patient appointments.

To assess the generalizability of these results to the broader profession, sample characteristics from the current study were compared to those collected in the 2015 ABC practice analysis.(28) This comparison revealed that a higher percentage of participants in the current study were women and had a master’s-level education, results that likely reflect ongoing shifts in the prosthetics profession as a whole. An increasing number of women have been certified in prosthetics since 2015, with more women than men obtaining their certification in recent years.

In addition, the proportion of prosthetics practitioners in the US with a master’s degree has increased steadily since 2015 due to the profession’s recent transition to an entry-level master’s degree.(39) The sample for the current study was also younger and had fewer years in practice than the ABC practice analysis sample. The larger proportions of practitioners in the sample who are early in their careers partly explain the percentage of women and practitioners with a master’s level of education in the current sample. Collectively, these findings suggest that results from this study likely reflect experiences, attitudes, and perceptions of younger practitioners who have completed master’s programs, and have less clinical experience than the average respondent in the 2015 ABC practice analysis.

Strengths and Limitations

The survey in this study asked participants about their practice environment, habits, and attitudes related to outcomes measurement. Collectively, results from this study provide a comprehensive and contemporary assessment of the prosthetics profession. Further, this study included a large sample of prosthetic providers, and sample characteristics were assessed against a recent professional practice analysis(28) to ascertain the generalizability of study results. Limitations to this work include a sample weighted more towards younger clinical professionals in prosthetics than the profession. Also, only a small number of study participants were prosthetic assistants, so study findings should not be generalized to prosthetic assistants. Further, the survey administered in this study did not include questions about how outcomes data is collected, stored, or aggregated across clinics. Soliciting information about technical issues, such as these, could be an emphasis in future studies. In addition, while prosthetics outcome measurement is conducted by a multidisciplinary team of medical professionals, this study included only prosthetists and prosthetic assistants. Future research should assess outcomes measurement in prosthetics care with other professional groups, such as physical therapists or physiatrists. And finally, it is possible that prosthetists and prosthetist assistants were more likely to respond to the survey if they were interested in outcomes measurement, representing a potential response bias. We have mitigated the influence of this potential bias by comparing our sample characteristics to the ABC Practice Analysis survey and discussing the generalizability of study findings with respect to differences seen between samples.

Conclusions

Outcomes measurement is an integral part of modern prosthetic care. Strategies to improve efficiency of administration and promote standardization across practitioners and clinics are needed to facilitate routine use of outcome measures in clinical practice. An understanding of current perceptions and feasibility of outcomes measurement can inform the selection of specific measures for use in clinical practice, and should guide the development of new self-reported surveys and performance-based tests.

Abbreviations:

2MWT

Two-minute Walk Test

ABC

Activities-Specific Balance Confidence Scale

ABC

American Board of Certification in Prosthetics, Orthotics, and Pedorthics

AMP

Amputee Mobility Predictor

BOC

Board of Certification/Accreditation

CHAMP

Comprehensive High-level Activity Mobility Predictor

LCI

Locomotor Capabilities Index

LLPR

Limb Loss and Preservation Registry

PEQ

Prosthetic Evaluation Questionnaire

PLUS-M

Prosthetic Limb Users Survey of Mobility

TAPES

Trinity Amputation and Prosthesis Experience Scales

TUG

Timed Up-and-Go