Measurement properties of painDETECT: Rasch analysis of responses from community-dwelling adults with neuropathic pain

Abstract

BackgroundpainDETECT (PD-Q) is a self-reported assessment of pain qualities developed as a screening tool for pain of neuropathic origin. Rasch analysis is a strategy for examining the measurement characteristics of a scale using a form of item response theory. We conducted a Rasch analysis to consider if the scoring and measurement properties of PD-Q would support its use as an outcome measure.MethodsRasch analysis was conducted on PD-Q scores drawn from a cross-sectional study of the burden and costs of NeP. The analysis followed an iterative process based on recommendations in the literature, including examination of sequential scoring categories, unidimensionality, reliability and differential item function. Data from 624 persons with a diagnosis of painful diabetic polyneuropathy, small fibre neuropathy, and neuropathic pain associated with chronic low back pain, spinal cord injury, HIV-related pain, or chronic post-surgical pain was used for this analysis.ResultsPD-Q demonstrated fit to the Rasch model after adjustments of scoring categories for four items, and omission of the time course and radiating questions. The resulting seven-item scale of pain qualities demonstrated good reliability with a person-separation index of 0.79. No scoring bias (differential item functioning) was found for this version.ConclusionsRasch modelling suggests the seven pain-qualities items from PD-Q may be used as an outcome measure. Further research is required to confirm validity and responsiveness in a clinical setting.Electronic supplementary materialThe online version of this article (doi:10.1186/s12883-017-0825-2) contains supplementary material, which is available to authorized users.

Measurement Properties of the SF-MPQ-2 Neuropathic Qualities Subscale in Persons with CRPS: Validity, Responsiveness, and Rasch Analysis

“…( 16) The SF-MPQ2 subscale for neuropathic qualities was considered appropriate to address the important domain of pain qualities. (5) While many other measures of neuropathic pain are available, our concerns were 1) many were developed with the intent to discriminate between nociceptive and neuropathic pain features, rather than to measure the severity or impact of neuropathic pain, (17)(18)(19)(20) or 2) lacked requisite evidence for test-retest reliability and responsiveness. (21) , (22) Further, the brevity of including a brief scale or subscale was desirable, to minimize participant burden related to a core set of measures.…”

Accuracy of neuropathic pain measurements in patients with symptoms of polyneuropathy: validation of painDETECT, Self-Completed Leeds Assessment of Neuropathic Symptoms and Signs, and Douleur Neuropathique 4

“…This is in concordance with earlier studies on all 3 tools, across an array of different patient populations. 1,7,8,11,12,16,21,25,27,32,40,48,53,56,59,60,64,65,67,68 By themselves, "easy items" can be expected to be sensitive, with discriminative power in patients with few symptoms. 15 However, numbness, tingling, and pins and needles are also cardinal symptoms of polyneuropathy, that is, hypoesthesia and paraesthesia in the feet.…”

Use of the painDETECT to discriminate musculoskeletal pain phenotypes

“…A final score between − 1 to 38 can be achieved by summing up the scores given in each domain. The painDETECT is validated for a large number of neuropathic pain conditions [28][29][30]. It was also validated for use in mixed pain conditions such as rheumatoid arthritis, osteoarthritis, cancer pain, and lumbar spondylolisthesis [25].…”

“…The optimal cut off point was established at 40/100 in patients with central sensitivity syndrome [34,35]. Also, the severity of CS-related sign and symptoms has been classified into sub-clinical (0-29), mild [29,30,[32][33][34][35][36][37][38][39], moderate [40][41][42][43][44][45][46][47][48][49], severe [50][51][52][53][54][55][56][57][58][59] and extreme (60-100), where higher scores indicate an increase in the severity of symptoms. The Brazilian version of the CSI demonstrated strong psychometric properties [36].…”