Validity and Test-Retest Reliability of the Dutch Modified Perceived Deficits Questionnaire to Examine Cognitive Symptoms in Women with Chronic Whiplash, Chronic Idiopathic Neck Pain, and Fibromyalgia

INTRODUCTION

Until now, only reliability and validity of the English version of the modified Perceived Deficits Questionnaire (mPDQ) have been investigated.

OBJECTIVE

The aim of this study was to translate the mPDQ into Dutch and evaluate its validity and reliability as an assessment tool for self-perceived cognitive problems in patients with chronic whiplash-associated disorders (CWAD), chronic idiopathic neck pain (CINP), and fibromyalgia (FM).

METHODS

A case-control study was performed with a volunteer sample of 13 women with CWAD, 18 with CINP, and 33 with FM, and 33 women who were healthy and free of pain. The mPDQ was first translated into Dutch, and its test-retest reliability, internal consistency, and discriminative power were examined.

RESULTS

The intraclass correlation coefficients were higher than 0.74. Cronbach's α values ranged between 0.71 and 0.95. Total mPDQ scores were significantly higher (P < 0.017) in FM and CWAD patients compared to healthy controls. Furthermore, participants performed the Stroop task and the psychomotor vigilance task (PVT), 2 neuropsychological computer-based cognitive performance tests. Correlations between the mPDQ total score and the cognitive performance tests were evaluated. Significant moderate to high correlations were found in all study samples between total mPDQ score and objective cognitive tests (Spearman correlation coefficient = 0.35 to 0.80; P < 0.05).

CONCLUSION

Therefore, the Dutch version of the mPDQ showed high test-retest reliability and high internal consistency, and was able to distinguish CWAD and FM patients from healthy controls.

PERSPECTIVE

This article presents the validity and test-retest reliability of the Dutch mPDQ. This measure could help clinicians who seek a reliable and user-friendly way to assess cognitive symptoms in chronic pain patients.

Differences in white matter structure and cortical thickness between patients with traumatic and idiopathic chronic neck pain: Associations with cognition and pain modulation?

Brain alterations are hypothesized to be present in patients with chronic whiplash-associated disorders (CWAD). The aim of this case-control study was to examine alterations in cortical thickness and white matter (WM) structure, and the presence of brain microhemorrhages in a patient group encountering chronic neck pain of traumatic origin (i.e., CWAD) when compared with a patient group characterized by nontraumatic chronic neck pain [i.e., chronic idiopathic neck pain (CINP)], and healthy controls. Furthermore, we aimed to investigate associations between brain structure on one hand and cognitive performance and central sensitization (CS) on the other hand. T1-weighted, diffusion-weighted and T2*-weighted magnetic resonance images of the brain were acquired in 105 women (31 controls, 37 CINP, 37 CWAD) to investigate regional cortical thickness, WM structure, and microhemorrhages, respectively. Next, cognitive performance, and CS encompassing distant hyperalgesia and conditioned pain modulation (CPM) efficacy were examined. Cortical thinning in the left precuneus was revealed in CWAD compared with CINP patients. Also, decreased fractional anisotropy, together with increased values of mean diffusivity and radial diffusivity could be observed in the left cingulum hippocampus and tapetum in CWAD compared with CINP, and in the left tapetum in CWAD patients compared with controls. Moreover, the extent of WM structural deficits in the left tapetum coincided with decreased CPM efficacy in the CWAD group. This yields evidence for associations between decreased endogenous pain inhibition, and the degree of regional WM deficits in CWAD. Our results emphasize the role of structural brain alterations in women with CWAD compared with CINP.