University Hospital Münster, Münster, Germany.
Department of Dermatology, Venereology and Allergology, Wroclaw Medical University, Wroclaw, Poland.
J Eur Acad Dermatol Venereol. 2022 Apr;36(4):573-581. doi: 10.1111/jdv.17870. Epub 2022 Feb 14.
Study TR03 evaluated the safety and efficacy of nalbuphine ER for prurigo nodularis (PN; NCT02174419).
We conducted supplementary analyses to assess the psychometric properties of the Worst Itch Numeric Rating Scale (WI-NRS), the TR03 primary endpoint.
Study TR03 was a double-blind, placebo-controlled, phase 2 trial in PN patients with documented scores ≥5 on the WI-NRS (0 [no itch]-10 [worst itch imaginable]) on ≥5 of 7 days before baseline. Using TR03 data, the WI-NRS's psychometric properties, including reliability, validity and ability to detect change, were evaluated. A responder threshold was estimated to facilitate interpretation of WI-NRS score changes.
Amongst 62 treated patients, improvements in mean [SD] (median) WI-NRS scores were observed between baseline (8.2 [1.21] (8.1)) and week 10 (5.8 [2.43] (6.0)). The WI-NRS had an intraclass correlation coefficient of 0.96 (95% confidence interval, 0.93-0.98) in 42 patients who had stable Itch verbal rating scale (VRS) scores from week 9-10, supporting strong test-retest reliability. Construct validity was supported, with strong correlations at week 10 with Average Itch NRS (r = 0.87) and Itch VRS single-day/weekly mean scores (r = 0.81/0.89) and moderate correlations with ItchyQoL™ total/domain scores (r = 0.41-0.43). The WI-NRS discriminated between predefined severity subgroups based on the Itch VRS and detected changes in itching severity (effect-size estimate: -2.05; standardized response mean: -1.21). An anchor-based threshold based on a two-category improvement in the single-day Itch VRS suggests a responder threshold of ≥3.8 points (~40% improvement).
The WI-NRS demonstrates good measurement properties, supporting its use in evaluating treatment change in PN.
TR03 研究评估了纳布啡 ER 治疗结节性痒疹（PN；NCT02174419）的安全性和疗效。
我们进行了补充分析，以评估主要终点——最差瘙痒数字评定量表（WI-NRS）的心理计量学特性。
TR03 是一项针对 PN 患者的双盲、安慰剂对照、2 期试验，这些患者在基线前至少 7 天的 WI-NRS（0 [无瘙痒]-10 [可想象的最严重瘙痒]）上记录了≥5 分，且得分≥5 分。使用 TR03 数据评估了 WI-NRS 的心理计量学特性，包括可靠性、有效性和检测变化的能力。估计了一个应答阈值，以方便解释 WI-NRS 评分变化。
在 62 名接受治疗的患者中，基线时（8.2 [1.21]（8.1））和第 10 周时（5.8 [2.43]（6.0）），平均[标准差]（中位数）WI-NRS 评分均有改善。在 42 名第 9-10 周瘙痒口头评定量表（VRS）评分稳定的患者中，WI-NRS 的组内相关系数为 0.96（95%置信区间，0.93-0.98），支持其具有较强的重测信度。结构效度也得到支持，第 10 周时与平均瘙痒 NRS（r=0.87）和瘙痒 VRS 单日/每周平均评分（r=0.81/0.89）呈强相关，与 ItchyQoL™总评分/各域评分呈中度相关（r=0.41-0.43）。WI-NRS 根据瘙痒 VRS 区分了预先设定的严重程度亚组，并检测到瘙痒严重程度的变化（效应大小估计值：-2.05；标准化反应均值：-1.21）。基于瘙痒 VRS 单日评分改善两个等级的锚定阈值表明，应答阈值为≥3.8 分（约 40%的改善）。
WI-NRS 具有良好的测量特性，支持其在评估 PN 治疗变化中的应用。
