Concurrent Validity of PROMIS With DASH and DVPRS in Transhumeral Amputees

Abstract

Background:

We sought to assess whether select domains of the Patient-Reported Outcomes Measurement Information System (PROMIS) significantly correlate with the Disabilities of the Arm, Shoulder, and Hand (DASH) score and the Defense and Veterans Pain Rating Scale (DVPRS) among transhumeral amputees.

Methods:

We prospectively administered DASH, DVPRS, and PROMIS (including Upper Extremity, Pain Interference, and Pain Behavior domains) testing to patients presenting for consideration of osseointegration after transhumeral amputation. Concurrent validity was assessed via Pearson correlation testing.

Results:

The mean DASH score of the cohort was 32.8. The mean DVPRS score was 1.8. The mean PROMIS scores were 33.8, 50.5, and 50.6 for Upper Extremity, Pain Interference, and Pain Behavior domains, respectively. Pearson testing demonstrated a significant, inverse correlation between DASH and PROMIS Upper Extremity scores (r = −0.85, P = .002). There was also significant correlation between DVPRS and PROMIS Pain Interference scores (r = 0.69, P = .03). The PROMIS Pain Behavior domain did not significantly correlate with either DASH or DVPRS.

Conclusions:

Patient-Reported Outcomes Measurement Information System Upper Extremity and Pain Interference scores demonstrated significant concurrent validity with traditional measures (DASH and DVPRS) of patient-reported outcome in our population of transhumeral amputees.

Introduction

The Disabilities of the Arm, Shoulder, and Hand (DASH) score has historically been used to measure functional outcomes and the impact of interventions in transhumeral amputees.^1-4 Based on a 30-item, self-reported questionnaire employing a Likert grading scale, the DASH score ranges from 0, indicating no disability, to 100, indicating maximum disability. ⁵ The Defense and Veterans Pain Rating Scale (DVPRS), a graphic tool similar to the Visual Analog Scale, is a 0- to 10-point scale that has been validated in the military population as a measure of pain intensity, and has been adopted to track pain longitudinally in this cohort.^6,7

More recently, computerized adaptive testing-based tools, such as the Patient-Reported Outcomes Measurement Information System (PROMIS), have gained traction.^8,9 Employing item response theory to optimize questionnaire administration, the National Institutes of Health developed PROMIS to use an algorithm which bases question selection on a preceding answer. ¹⁰ This allows for score generation after 4 to 6 questions, typically taking a respondent less than 1 minute to complete each domain. ¹¹ Patient-Reported Outcomes Measurement Information System scores are designed to follow a normal distribution, with mean T score of 50 and standard deviation of 10. This allows for more intuitive score interpretation. For the Upper Extremity domain, higher scores indicate better function, and for the Pain Interference and Pain Behavior domains, higher scores indicate more severe pain.^12-14

Patient-Reported Outcomes Measurement Information System presents an opportunity for researchers and study participants alike, offering significantly reduced administrative burden and faster time-to-completion compared with legacy patient-reported outcome measures (PROMs), in addition to greater precision of scores and reduced floor and ceiling effects.^15-18 This is particularly relevant for transhumeral amputees as emerging technologies—such as self-contained osseointegrated neuromuscular prostheses—demand careful study of patient-reported outcomes. Reduction of survey fatigue among respondents will maximize participation in such research. ¹⁹ However, before adopting PROMIS, it is important to first establish concurrent validity between this novel tool and the legacy PROMs it may eventually supplant.^20,21

Thus, we sought to answer the following: In a population of transhumeral amputees, do select domains of the PROMIS significantly correlate with DASH score and the DVPRS?

Materials and Methods

After obtaining institutional review board approval, we prospectively administered DASH, DVPRS, and PROMIS (including Upper Extremity, Pain Interference, and Pain Behavior domains) testing to patients presenting to our institution’s Multidisciplinary Osseointegration Clinic between 2016 and 2020. These patients had previously sustained transhumeral amputation, with poor tolerance of conventional socket prostheses. Patients with concurrent peripheral vascular disease, diabetes mellitus, or infection of residual limb were not eligible for consideration of osseointegration. All questionnaires were electronically administered on iPad via REDCap (Research Electronic Data Capture, Vanderbilt University, Nashville, Tennessee) as an intake survey at the initial clinical visit. Patient-Reported Outcomes Measurement Information System domains were administered as adaptive tests. None of the questionnaires were altered for the purpose of our study.

Concurrent validity was assessed via Pearson correlation testing. Data analysis was conducted in IBM SPSS v27.0 (IBM, Armonk, New York), with significance defined at α = 0.05. Correlation strength was interpreted by Evans criteria: r value less than 0.2 indicated very weak; 0.2 to 0.39 indicated weak; 0.4 to 0.59 indicated moderate; 0.6 to 0.79 indicated strong; and 0.8 or greater indicated very strong correlation. ²²

Results

We obtained PROMs for 10 transhumeral amputees presenting for consideration of osseointegration between 2016 and 2020 (Table 1). All 10 patients were male, with mean age 35.4 years (standard deviation, 13.4; range, 22-62 years). All patients sustained transhumeral amputation secondary to trauma, with 8 of 10 (80%) occurring from combat-related blast injury (motor vehicle and boating accidents accounted for the remaining 2). Mean time between amputation and presentation was 8.7 years (standard deviation, 5.1; range, 0.5-18 years). A majority of amputations—8 of 10 (80%)—occurred on the nondominant arm. No significant differences in DASH, DVPRS, or PROMIS scores were detected on the basis of the affected extremity’s dominance status.

Table 1.

Cohort DASH, DVPRS, and PROMIS Scores.

Measure	Mean	Range	SD
DASH	32.8	0-77.5	23.3
DVPRS	1.8	0-4	1.5
PROMIS
Upper Extremity	33.8	23.6-39.5	5.3
Pain Interference	50.5	40.7-58.3	7.3
Pain Behavior	50.6	36.7-59.5	9.8

Note. DASH = Disabilities of the Arm, Shoulder, and Hand; DVPRS = Defense and Veterans Pain Rating Scale; PROMIS = Patient-Reported Outcomes Measurement Information System.

Pearson testing demonstrated a significant, inverse correlation between DASH and PROMIS Upper Extremity scores (r = −0.85, P = .002; Figure 1). Per Evans, this indicated very strong correlation. There was also significant, positive correlation between DVPRS and PROMIS Pain Interference scores (r = 0.69, P = .03; Figure 2). Per Evans, this indicated strong correlation. The PROMIS Pain Behavior domain did not significantly correlate with either DASH (r = 0.17, P = .64) or DVPRS (r = 0.45, P = .2).

Figure 1.

Scatterplot of cohort DASH and PROMIS Upper Extremity scores (r = −0.85, P = .002).

Note. DASH = Disabilities of the Arm, Shoulder, and Hand; PROMIS = Patient-Reported Outcomes Measurement Information System.

Figure 2.

Scatterplot of cohort DVPRS and PROMIS Pain Interference scores (r = 0.69, P = .03).

Note. DVPRS = Defense and Veterans Pain Rating Scale; PROMIS = Patient-Reported Outcomes Measurement Information System.

Discussion

In our population of transhumeral amputees, PROMIS Upper Extremity and PROMIS Pain Interference scores demonstrated significant concurrent validity with DASH and DVPRS, respectively. According to Evans, correlation strength may be interpreted by using r: r value less than 0.2 indicates very weak; 0.2 to 0.39 indicates weak; 0.4 to 0.59 indicates moderate; 0.6 to 0.79 indicates strong; and 0.8 or greater indicates very strong correlation. ²² Thus, PROMIS Upper Extremity and DASH exhibited very strong correlation. Patient-Reported Outcomes Measurement Information System Pain Interference and DVPRS, by Evans criteria, exhibited strong correlation. The mean DASH score of our cohort, 32.8, falls in line with previously published reports of major upper extremity amputees, whose mean DASH scores range from 22 to 54.^1-4

The prospective nature of our investigation, statistical robustness of our correlations, and relatively large cohort of transhumeral amputees—in comparison to the extant literature—are the primary strengths of our study. In terms of limitations, our patient population was entirely male and had their amputations in the setting of trauma—most often combat-related blast injury. Therefore, these results may not be generalizable to other transhumeral amputees, such as those amputated in the setting of tumor resection, infection, or intractable complex regional pain syndrome.

Multiple previous investigations have demonstrated the advantages of PROMIS over legacy patient-reported outcomes measures, including increased precision, reduced floor and ceiling effects, faster time to completion, and more intuitive interpretation of scores.^11,15-18,23 Patient-Reported Outcomes Measurement Information System provides relative ease of administration and reduction of question burden, benefiting researchers and study participants alike. In this study, we demonstrated the concurrent validity of select PROMIS domains with legacy measures of patient function and pain—DASH and DVPRS—in our cohort of transhumeral amputees. By establishing robust correlation with legacy measures, we contend that PROMIS may ultimately supplant legacy measures in future investigations of transhumeral amputees. Forthcoming areas of study for PROMIS in this patient population include establishing minimal clinically important differences and evaluating responsiveness. Looking forward, PROMIS may better serve our efforts to longitudinally evaluate the outcomes of future interventions—such as self-contained osseointegrated neuromuscular prostheses—for these patients.