Povero Massimiliano, Turco Paola, Bonadiman Luca, Dal Negro Roberto W
AdRes Health Economics and Outcome Research, Turin.
Research & Clinical Governance, Verona.
Multidiscip Respir Med. 2020 Jul 21;15(1):659. doi: 10.4081/mrm.2020.659. eCollection 2020 Jan 28.
The choice of the Dry Powder Inhaler (DPI) to prescribe is a critical issue. The estimation of DPIs usability depends on the objective assessment of several indices related to both subjective and objective determinants. The Global Usability Score (GUS) Questionnaire is a comprehensive tool usable for checking, comparing, and ranking inhalers' usability objectively in real life, but it takes some time to fill.
The aim of this study was to favour the quicker check of DPIs usability in clinical practice by means of a simplified short-form GUS (S-GUS) Questionnaire, while maintaining the high specificity and sensitivity of the original, extended version of the Questionnaire (O-GUS questionnaire).
The usability of the six most prescribed DPIs was assessed in 222 patients with persistent airway obstruction and needing long-term inhalation treatments. LASSO regression and multicollinearity test were used to select the subset of questions of the O-GUS questionnaire, with the highest information power. Each item was then scored using the corresponding coefficient in the linear regression (normalized at 50 as the O-GUS score). Agreement between the original and the short-form questionnaire was evaluated using the Cohen's kappa statistic (κ). The overall S-GUS values obtained for each DPI were then compared to those from the O-GUS, in the same patients, using a Bayesian indirect comparison (IC) model.
After the statistical selection of the items mostly contributing to the overall score, the novel S-GUS questionnaire consists of twelve items only. Nine items are related to patients' opinion before DPIs handling, and three to the nurse's assessment after DPIs practicality. O-GUS and S-GUS score were strongly correlated (R=0.9843, <0.0001) and the usability score calculated for each DPI by means of the O- and of S- GUS overlapped almost completely (κ=84.5%, 95% CI 81.3% to 89.2%). Furthermore, S-GUS was much faster to complete than O-GUS (mean time 6.1 23.4 minutes, <0.001). Estimates of S-GUS, obtained from the IC model, allowed to propose a simple classification of usability: "good" by GUS values >25; "pretty good" by values ≤25≥15, and "insufficient" by values <15.
The S-GUS proves as much specific and suitable as the extended O-GUS questionnaire in measuring DPIs usability, while maintaining the same high sensitivity. As the time required for its use is quite shorter, S-GUS is also particularly suitable and helpful in current clinical practice.
选择合适的干粉吸入器（DPI）进行处方是一个关键问题。DPI可用性的评估取决于对与主观和客观决定因素相关的多个指标的客观评估。全球可用性评分（GUS）问卷是一种全面的工具，可用于在现实生活中客观地检查、比较和排名吸入器的可用性，但填写该问卷需要一些时间。
本研究的目的是通过简化的简短形式GUS（S-GUS）问卷，在临床实践中更快速地检查DPI的可用性，同时保持原始扩展版问卷（O-GUS问卷）的高特异性和敏感性。
对222例持续性气道阻塞且需要长期吸入治疗的患者，评估了六种最常用的DPI的可用性。使用LASSO回归和多重共线性检验来选择O-GUS问卷中信息能力最高的问题子集。然后使用线性回归中的相应系数对每个项目进行评分（以50作为O-GUS评分进行标准化）。使用Cohen's kappa统计量（κ）评估原始问卷和简短问卷之间的一致性。然后，使用贝叶斯间接比较（IC）模型，将同一患者中每个DPI获得的总体S-GUS值与O-GUS的值进行比较。
在对总体评分贡献最大的项目进行统计选择后，新的S-GUS问卷仅包含12个项目。九个项目与患者在操作DPI之前的意见相关，三个项目与护士在DPI实际操作后的评估相关。O-GUS和S-GUS评分高度相关（R = 0.9843，<0.0001），并且通过O-GUS和S-GUS为每个DPI计算的可用性评分几乎完全重叠（κ = 84.5%，95% CI 81.3%至89.2%）。此外，S-GUS完成起来比O-GUS快得多（平均时间6.1±23.4分钟，<0.001）。从IC模型获得的S-GUS估计值允许提出一个简单的可用性分类：GUS值>25为“良好”；值≤25≥15为“相当好”，值<15为“不足”。
在测量DPI可用性方面，S-GUS与扩展的O-GUS问卷一样具有特异性和适用性，同时保持相同的高敏感性。由于其使用所需时间短得多，S-GUS在当前临床实践中也特别合适且有帮助。
