Hernandez Gimena, Garin Olatz, Dima Alexandra L, Pont Angels, Martí Pastor Marc, Alonso Jordi, Van Ganse Eric, Laforest Laurent, de Bruin Marijn, Mayoral Karina, Serra-Sutton Vicky, Ferrer Montse
Health Services Research Group, Hospital del Mar Medical Research Institute, Barcelona, Spain.
Department of Paediatrics, Obstetrics and Gynaecology and Preventive Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.
J Med Internet Res. 2019 Jan 23;21(1):e10178. doi: 10.2196/10178.
The EuroQol-5 Dimension (EQ-5D), developed in 1990, is a most widely used generic tool to measure the health-related quality of life (HRQoL) and considered suitable for patients with asthma. In 2009, the EuroQol Group developed a new EQ-5D version to overcome limitations related to its consistently reported high ceiling effect. To enhance the sensitivity for assessing the HRQoL in further patient populations, the number of responses of EQ-5D was increased from 3 to 5 levels (EQ-5D-5L). Moreover, the availability of well-defined requirements for its Web-based administration allows EQ-5D-5L use to monitor the HRQoL in electronic health (eHealth) programs. No study has evaluated the metric properties of the new EQ-5D-5L in patients with asthma yet.
This study aims to examine the distribution, construct validity, and reliability of the new EQ-5D-5L questionnaire administered online to adults with asthma.
We evaluated patients with asthma (age: 18-40 years) from a primary care setting in France and England, who self-completed the EQ-5D-5L questionnaire online. The inclusion criteria were persistent asthma defined as >6 months of prescribed inhaled corticosteroids and long-acting beta-agonists or inhaled corticosteroids alone during the 12 months prior to inclusion. The EQ-5D index was obtained by applying the English preference value set for the new EQ-5D-5L and the French 3L-5L crosswalk value set. Both value sets produced single preference-based indices ranging from 1 (best health state) to negative values (health states valued as worse than death), where 0=death, allowing the calculation of quality-adjusted life years. Responses to dimensions and index distribution, including ceiling and floor effects, were examined. The construct validity was assessed by comparing the means of known groups by analyses of variance and calculation of effect sizes.
Of 312 patients answering the baseline Web-based survey, 290 completed the EQ-5D-5L (93%). The floor effect was null, and the ceiling effect was 26.5% (74/279). The mean EQ-5D-5L index was 0.88 (SD 0.14) with the English value set and 0.83 (SD 0.19) with the French 3L-5L crosswalk value set. In both indices, large effect sizes were observed for known groups defined by the Asthma Control Questionnaire (1.06 and 1.04, P<.001). Differences between extreme groups defined by chronic conditions (P=.002 and P=.003 for the English value set and French 3L-5L crosswalk value set, respectively), short-acting beta-agonists (SABAs) canisters in the last 12 months (P=.02 and P=.03), or SABA use during the previous 4 weeks (P=.03 and P=.01) were of moderate magnitude with effect sizes around 0.5.
The new EQ-5D-5L questionnaire has an acceptable ceiling effect, a good construct validity based on the discriminant ability for distinguishing among health-related known groups, and high reliability, supporting its adequacy for assessing the HRQoL in patients with asthma. EQ-5D-5L completion by most Web-based respondents supports the feasibility of this administration form.
欧洲五维健康量表（EQ - 5D）于1990年编制，是一种应用广泛的通用工具，用于测量健康相关生活质量（HRQoL），被认为适用于哮喘患者。2009年，欧洲五维健康量表小组开发了新的EQ - 5D版本，以克服其一直报道的高天花板效应相关的局限性。为了提高在更多患者群体中评估HRQoL的敏感性，EQ - 5D的反应等级从3级增加到5级（EQ - 5D - 5L）。此外，基于网络管理的明确要求使得EQ - 5D - 5L能够用于监测电子健康（eHealth）项目中的HRQoL。尚无研究评估新的EQ - 5D - 5L在哮喘患者中的测量特性。
本研究旨在检验在线应用于成年哮喘患者的新EQ - 5D - 5L问卷的分布、结构效度和信度。
我们评估了来自法国和英国基层医疗机构的哮喘患者（年龄：18 - 40岁），他们通过网络自行完成EQ - 5D - 5L问卷。纳入标准为持续性哮喘，定义为在纳入前12个月内使用吸入性糖皮质激素和长效β受体激动剂或仅使用吸入性糖皮质激素超过6个月。EQ - 5D指数通过应用新EQ - 5D - 5L的英国偏好值集和法国3L - 5L交叉walk值集获得。两个值集均产生基于偏好的单一指数，范围从1（最佳健康状态）到负值（健康状态被评估为比死亡更差），其中0 = 死亡，从而能够计算质量调整生命年。检查维度和指数分布的反应，包括天花板效应和地板效应。通过方差分析比较已知组的均值并计算效应大小来评估结构效度。
在312名回答基线网络调查的患者中，290名完成了EQ - 5D - 5L（93%）。地板效应为零，天花板效应为26.5%（74/279）。使用英国值集时，EQ - 5D - 5L指数的均值为0.88（标准差0.14），使用法国3L - 5L交叉walk值集时为0.83（标准差0.19）。在两个指数中，由哮喘控制问卷定义的已知组观察到较大的效应大小（分别为1.06和1.04，P <.001）。由慢性病定义的极端组之间的差异（英国值集和法国3L - 5L交叉walk值集分别为P =.002和P =.003）、过去12个月内短效β受体激动剂（SABA）罐的使用情况（P =.02和P =.03）或前4周内SABA的使用情况（P =.03和P =.01）具有中等程度的差异，效应大小约为0.5。
新的EQ - 5D - 5L问卷具有可接受的天花板效应，基于区分健康相关已知组的判别能力具有良好的结构效度，并且具有高信度，支持其适用于评估哮喘患者的HRQoL。大多数基于网络的受访者完成EQ - 5D - 5L支持了这种管理形式的可行性。
