Psychometric properties of a German version of the neck pain and disability scale

The aim of this study is to evaluate the validity and the psychometric properties of a German version of the 20-item neck pain and disability scale (NPAD) for use in primary care settings. Four hundred and forty-eight participants from 15 general practices in the area of Göttingen Germany completed a multidimensional questionnaire including a newly developed German version of the NPAD (NPAD-d) and self-reported demographic and clinical information. Reliability was tested using Cronbach’s alpha. Item-to-total score correlations were analysed. Factor structure was explored by using unrestricted principal factor analysis. Construct validity of the NPAD-d was evaluated by simple correlation analyses (Pearson’s rho) with social and clinical characteristics. The discriminative abilities of the NPAD-d were examined by comparing differences between subgroups stratified on non-NPAD-d pain related characteristics using t tests for mean scores. Cronbach’s alpha of NPAD-d was 0.94. Item-to-total scale correlations ranged between 0.414 and 0.829. Exploratory principal factor analysis indicated that the NPAD-d covers one factor with an explained variance of 48%. Correlation analysis showed high correlations with criterion variables. The NAPD-d scores of subgroups of patients were significantly different showing good discriminative validity of the scale. The NPAD-d demonstrated good validity and reliability in this general practice setting. The NPAD-d may be useful in the clinical assessment process and the management of neck pain

Reliability, validity, and responsiveness of the Japanese version of the Neck Pain and Disability Scale

Abstract Background Until recently, no Japanese versions have existed of the more popular, patient-reported disability questionnaires for neck pain. This study aimed to test the reliability, validity, and responsiveness of the Japanese version of the Neck Pain and Disability Scale (NPDS), one of the most widely used questionnaires in patients with neck pain. Methods In this validation study, 167 outpatients with neck pain participated. Patients received the NPDS and the Medical Outcome Study Short Form 36-item Health Survey (SF-36), and used Visual Analog Scales (VASs) to assess pain and global health. To examine test-retest reliability, patients who were considered stable by clinicians were given the NPDS 2 weeks after baseline. To examine responsiveness, patients who had not undergone treatment at the time of the first data collection or had no change in treatment over 3 months were studied again 2 weeks after starting a new medication or physical therapy. Results Of the 167 participants, 143 completed the questionnaires (85.6%). Factor analysis showed two factors, defined as neck-pain-related disability (factor 1) and neck-related pain (factor 2). Cronbach's a coefficient for factor 1, factor 2, and total score was 0.94, 0.93, and 0.96. The intra-class correlation coefficients for the 19 more stable patients were 0.79, 0.88, and 0.87. For concurrent validity, the correlation between NPDS subscales and total score and SF-36 subscale scores ranged from r = -0.54 to -0.22 (p \ 0.01). Correlations between the NPDS subscales and total score and VAS of pain ranged from 0.56 to 0.77 (p \ 0.01) and those for VAS of global health ranged from 0.48 to 0.63 (p \ 0.01). The NPDS subscales and total scores of the 41 patients retested after treatment were significantly improved. Electronic supplementary material The online version of this articl

How well do questionnaires on symptoms in neck-shoulder disorders capture the experiences of those who suffer from neck-shoulder disorders? A content analysis of questionnaires and interviews

<p>Abstract</p> <p>Background</p> <p>Previous research has indicated neck-shoulder disorders to have a fluctuating course incorporating a variety of symptoms. These findings awoke our interest to make a comparison between symptoms experienced by people affected with the disorder and the content of questionnaires that assess pain and other symptoms in neck-shoulder disorders. Thus the aims of this study were: -to explore the symptoms experienced by people with non-specific neck-shoulder problems, as well as experiences of nuances and temporal variations (fluctuations) of symptoms; -to investigate which sources were used in the development of ten questionnaires for assessing pain and other symptoms in the neck-shoulder; -to analyse the item content of the questionnaires; -to analyse the correspondence between the item content of the questionnaires and the symptoms described by the informants.</p> <p>Methods</p> <p>Content analysis of interviews with 40 people with non-specific neck-shoulder pain, and 10 questionnaires used to assess pain and other symptoms in neck-shoulder disorders.</p> <p>Results</p> <p>The interviews revealed a variety of symptoms indicating a bodily, mental/cognitive, and emotional engagement, and more general and severe symptoms than are usually considered in neck-shoulder questionnaires. Taking all questionnaires together many of the symptoms were considered, but most questionnaires only included a few of them. The informants were able to distinguish fluctuation of symptoms, and a variety of different qualities which were not usually considered in the questionnaires. Only two questionnaires had made use of the opinions of affected people in the development.</p> <p>Conclusion</p> <p>Few of the questionnaires had made use of the experiences of affected people in the development. The correspondence between the symptoms expressed by those affected and the content of the questionnaires was low. A variety of symptoms were expressed by the interviewees, and the participants were also able to distinguish nuances and fluctuations of symptoms. The present study points to the importance of other aspects than just pain and physical functioning as clinical trial outcome measures related to neck-shoulder disorders. To develop a condition-specific questionnaire, it is important to decide on the specific symptoms for the condition. Using the experiences of those affected, in combination with relevant research and professional knowledge, can enhance the validity of the questionnaires.</p

Sensitivity to change of the Neck Pain and Disability Scale

The Neck Pain and Disability Scale (NPAD) is a 20-item instrument to measure neck pain and related disability. The aim of this study was to assess sensitivity to change of the NPAD. A total of 411 participants from 15 general practices in the middle of Germany completed a multidimensional questionnaire including the German version of the NPAD and self-reported demographic and clinical information. Sensitivity to change was analysed by linear regression analysis of the NPAD at follow-up and educational level, age class, depression, anxiety, and deficits in social support, respectively, and by Pearson’s correlation analyses between mean change in NPAD at follow-up and mean change in prognostic markers. Those having more than basic education (regression coefficient −7.2, p < 0.001) and/or being in a younger age class (−2.9, p = 0.020) consistently reported significantly lower average NPAD scores at follow-up compared to those with basic education and/or a older age class. In contrast, those who were classified to be depressed (regression coefficient 2.1, p < 0.001), anxious (1.9, p < 0.001), or having deficits in social support (5.5, p = 0.004) reported significantly higher NPAD scores. Change in depression, anxiety, and social support scale between baseline and follow-up was significantly correlated with change in the NPAD score. Hence, these data are in the direction anticipated across all baseline factors investigated. In conclusion, the NPAD seems to be a sensitive measure for use in clinical practice and future studies of neck pain and related disability

Neck Pain and Disability Scale and the Neck Disability Index: reproducibility of the Dutch Language Versions

The first aim of this study was to translate the Neck Pain and Disability Scale (NPAD) from English into Dutch producing the NPAD–Dutch Language Version (DLV). The second aim was to analyze test–retest reliability and agreement of the NPAD–DLV and the Neck Disability Index (NDI)–DLV. The NPAD was translated according to established guidelines. Thirty-four patients (mean age 37.5 years, 68% female) with chronic neck pain (CNP), within an outpatient rehabilitation setting, participated in this study. The NPAD–DLV and the NDI–DLV were filled out twice with a mean test–retest interval of 18 days. The intraclass correlation coefficient of the NPAD–DLV was 0.76 (95% confidence interval (CI) 0.57–0.87) and of the NDI–DLV 0.84 (95% CI 0.69–0.92). The limits of agreement of the NPAD–DLV and the NDI–DLV were, respectively, ±20.9 (scale 0–100) and ±6.5 (scale 0–50). The reliability of the NPAD–DLV and the NDI–DLV was acceptable for patients with CNP. The variation (‘instability’) in the NPAD–DLV total scores was relatively large and larger than the variation of the NDI–DLV