Psychometric evaluation of self-report outcome measures for prosthetic applications

Abstract

Documentation of clinical outcomes is increasingly expected in delivery of prosthetic services and devices. However, many outcome measures suitable for use in clinical care and research have not been psychometrically tested with prosthesis users. The aim of this study was to determine test-retest reliability, mode-of-administration (MoA) equivalence, standard error of measurement (SEM), and minimal detectable change (MDC) of standardized, self-report instruments that assess constructs of importance to people with lower limb loss. Prosthesis users (n=201) were randomly assigned to groups based on MoA (i.e., paper, electronic, or mixed-mode). Participants completed two surveys 2-3 days apart. Instruments included the Prosthetic Limb Users Survey of Mobility, Prosthesis Evaluation Questionnaire–Mobility Subscale, Activities-Specific Balance Confidence Scale, Quality of Life in Neurological Conditions–Applied Cognition/General Concerns, Patient Reported Outcomes Measurement Information System Profile, and Socket Comfort Score. Intraclass correlation coefficients indicated all instruments are appropriate for group-level comparisons and select instruments are suitable for individual-level applications. Several instruments showed evidence of possible floor and ceiling effects. All were equivalent across MoAs. SEM and MDC were quantified to facilitate interpretation of outcomes and change scores. These results can enhance clinicians' and researchers' ability to select, apply, and interpret scores from instruments administered to prosthesis users.

Retracted: Test‐Retest Reliability of Dynamic Balance Performance‐Based Measures Among Adults With a Unilateral Lower‐Limb Amputation

“…Participants also completed 2 self-report instruments, the Socket Fit Comfort Score (SFCS) and the Prosthetic Limb Users Survey of Mobility 12-item (PLUS-M), prior to performance testing. The SFCS asks the individual to rate their current prosthesis fit on a numeric rating scale from 0 (most uncomfortable socket fit) to 10 (most comfortable socket fit) [27] and has demonstrated test-retest reliability with ICCs varying from 0.63 to 0.79 [28]. The PLUS-M is a self-report instrument that assesses an individual's ability to carry out actions requiring use of both lower limbs that range from household ambulation to outdoor recreational activities [29].…”

“…The PLUS-M is a self-report instrument that assesses an individual's ability to carry out actions requiring use of both lower limbs that range from household ambulation to outdoor recreational activities [29]. The PLUS-M has established test-retest reliability (ICC = 0.97; 95% CI = 0.95-0.98) and convergent construct validity (ρ: 0.54-0.81); higher resultant t-scores correspond with greater mobility [28,30].…”

Laboratory- and community-based health outcomes in people with transtibial amputation using crossover and energy-storing prosthetic feet: A randomized crossover trial

“…Mobility was measured with the Prosthetic Limb Users Survey of Mobility (PLUS-M) version 1.2, a self-report instrument developed to be a brief, valid, and reliable measure of mobility. [ 31 , 32 ] PLUS-M is specific to measurement of mobility in prosthetic limb users and has been developed with data from over 1300 people with lower limb amputation. Internal consistency is greater than 0.9 and PLUS-M scores correlate with other measures of mobility in hypothesized magnitude and direction.…”

Mobility Analysis of AmpuTees (MAAT 4): classification tree analysis for probability of lower limb prosthesis user functional potential

“…Variables included within the CART analysis model for individuals with lower limb amputation included gender, height, weight, cause of amputation, history of smoking, body mass index (adjusted for limb loss [23,24]), comorbid health status and age. Additionally, three variables from patient-reported outcome measures were included, the satisfaction and quality of life measures from the Prosthesis Evaluation Questionnaire Well-Being subsection [25,26] and the Prosthetic Limb Users Survey of Mobility T-Score (PLUS-M TM ) [27][28][29]. For comorbid health, the Functional Comorbidity Index [30] was entered as an interval variable.…”