Basic Sciences Department, Faculty of Physical Therapy, Cairo University, Giza, Egypt.
Spine (Phila Pa 1976). 2013 May 1;38(10):E609-15. doi: 10.1097/BRS.0b013e31828b2d09.
Translation and psychometric testing.
To adapt the neck disability index (NDI) cross-culturally to Arabic language and to investigate the reliability and validity of the Arabic version of NDI in an Arabic-speaking sample with neck pain.
Although largely used, no previous reports exist on the translation process or the testing of the psychometric properties of the Arabic version of the NDI.
Cross-cultural adaptation of an outcome questionnaire. The English version of the NDI was translated into Arabic (NDI-Ar) and back-translated according to established guidelines. Sixty-five patients with neck pain completed the NDI -Ar twice during a 1-week period, to assess its test-retest reliability. Further psychometric testing was done by assessing internal consistency, construct validity (factor structure), and responsiveness.
The internal consistency value (Cronbach α) for the NDI-Ar was 0.89. The test-retest reliability (intraclass correlation coefficient) was excellent at 0.96 (95% confidence interval from 0.93 to 0.97). There was a significant correlation (r = 0.92, P < 0.05) between the scores obtained from the first administration of the NDI-Ar and the second administration. Factor analysis demonstrated a 2-factor structure, explaining 67.58% of total variance. The analysis of responsiveness was calculated with an unpaired t test after 1 week of treatment and demonstrating a statically significant difference between stable and improved patients (P < 0.05). The Spearman correlation coefficient (rS = 0.81; P = 0.000) revealed strong relation between the change in score in the NDI-Ar and global rating of change. No ceiling or floor effects were detected in the NDI-Ar.
The Arabic version of the NDI has a 2-factor 10-item structure and is a reliable, valid, and responsive tool that can be used to assess neck pain in Arabic-speaking patients with neck pain. Therefore, it can be recommended for clinical and research purposes.
翻译和心理计量学测试。
将颈部残疾指数（NDI）跨文化适应为阿拉伯语，并在患有颈部疼痛的阿拉伯语样本中研究 NDI 阿拉伯语版本的可靠性和有效性。
尽管 NDI 被广泛使用，但之前没有关于其翻译过程或心理计量特性测试的报告。
结果问卷的跨文化适应。根据既定指南，将 NDI 的英文版本翻译成阿拉伯语（NDI-Ar）并进行回译。65 名患有颈部疼痛的患者在一周内两次完成 NDI-Ar，以评估其测试-重测可靠性。通过评估内部一致性、结构有效性（因素结构）和反应性来进行进一步的心理计量学测试。
NDI-Ar 的内部一致性值（Cronbach α）为 0.89。测试-重测可靠性（组内相关系数）为 0.96（95%置信区间为 0.93 至 0.97），非常出色。NDI-Ar 的第一次和第二次测量之间的分数存在显著相关性（r = 0.92，P <0.05）。因子分析显示出 2 因素结构，解释了总方差的 67.58%。在治疗后 1 周进行的非配对 t 检验分析了反应性，并显示稳定和改善患者之间存在统计学显著差异（P <0.05）。NDI-Ar 中得分变化与总体变化评分之间的 Spearman 相关系数（rS = 0.81；P = 0.000）显示出很强的关系。在 NDI-Ar 中未发现上限或下限效应。
NDI 的阿拉伯语版本具有 2 个因素 10 个项目的结构，是一种可靠、有效且敏感的工具，可用于评估阿拉伯语颈部疼痛患者的颈部疼痛。因此，它可以推荐用于临床和研究目的。
