Wells Joshua, Mahendran Siva, Dolgin Kevin, Kayyali Reem
Department of Pharmacy, Kingston University, Kingston, UK.
Respiratory Department, Kingston Hospital NHS Foundation Trust, Kingston, UK.
Patient Prefer Adherence. 2023 Feb 19;17:457-472. doi: 10.2147/PPA.S394538. eCollection 2023.
People living with COPD who struggle to take their medicines often experience poorer health outcomes such as exacerbations of symptoms, more frequent and lengthy hospital admissions, and worsening mortality rates. This study aimed to evaluate the psychometric properties of the previously validated SPUR-27 model, a multi-factorial model of medication adherence.
This cross-sectional study was conducted with 100 adult patients living with COPD in a hospital setting in Southwest London. Medication adherence was assessed using a shortened SPUR model (SPUR-27) against the validated Inhaler Adherence Scale (IAS) as a comparator. In addition, objective medication adherence data, presented as the Medication Possession Ratio (MPR), were derived from patient medical and pharmacy records. The COPD Assessment Tool (CAT) score was used to examine the relationship between medication adherence and COPD symptom severity. Reliability of SPUR-27 was assessed using internal consistency estimates. Exploratory factor analysis, partial confirmatory factor analysis, and maximum likelihood analysis were conducted in conjunction with construct, concurrent, and known-group validity testing to explore the psychometric properties of the SPUR model in this population.
A 7-factor model for SPUR-27 was derived with adequate factor loadings. SPUR (α=0.893) observed strong internal consistency (>0.8). The model was significantly positively correlated with IAS score (<0.001) as well as MPR (<0.01). A significant (<0.01) relationship between poor medication adherence and worsening symptom severity, as defined by the CAT score, was identified for SPUR ( = 8.570) using Chi-Square analysis. Furthermore, SPUR-27 demonstrated early evidence of validity with good incremental fit indices: NFI (0.96), TFI (0.97), and CFI (0.93) were all reported as >0.9 in addition to the RMSEA, which was <0.08 (0.059).
SPUR demonstrated strong psychometric properties in patients living with COPD. Further work should look to examine the test-retest reliability of the model and its application in broader sample populations.
慢性阻塞性肺疾病（COPD）患者在服药方面存在困难，往往健康状况较差，例如症状加重、住院频率增加且住院时间延长，死亡率上升。本研究旨在评估先前验证的SPUR - 27模型的心理测量特性，这是一个药物依从性的多因素模型。
本横断面研究在伦敦西南部一家医院对100名成年COPD患者进行。使用简化的SPUR模型（SPUR - 27）评估药物依从性，并与经过验证的吸入器依从性量表（IAS）作为对照。此外，客观的药物依从性数据以药物持有率（MPR）表示，来自患者的医疗和药房记录。使用慢性阻塞性肺疾病评估工具（CAT）评分来检查药物依从性与COPD症状严重程度之间的关系。使用内部一致性估计评估SPUR - 27的可靠性。进行探索性因素分析、部分验证性因素分析和最大似然分析，并结合结构效度、同时效度和已知组效度测试，以探索该人群中SPUR模型的心理测量特性。
得出了一个具有适当因子载荷的SPUR - 27七因素模型。SPUR（α = 0.893）具有很强的内部一致性（>0.8）。该模型与IAS评分（<0.001）以及MPR（<0.01）呈显著正相关。使用卡方分析，对于SPUR（χ² = 8.570），确定了药物依从性差与CAT评分所定义的症状严重程度恶化之间存在显著（<0.01）关系。此外，可以早期证明SPUR - 27具有良好的效度，增量拟合指数良好：除RMSEA <0.08（0.059）外，NFI（0.96）、TFI（0.97）和CFI（0.93）均报告>0.9。
SPUR在COPD患者中表现出很强的心理测量特性。进一步的工作应着眼于检查该模型的重测信度及其在更广泛样本人群中的应用。
