ISPUP - EPIUnit, Universidade do Porto, Rua das Taipas, 4050-600, Porto, Portugal.
Centro de Medicina do Sono - Hospital CUF Porto, Estrada da Circunvalação, 4100-180, Porto, Portugal.
Support Care Cancer. 2017 Oct;25(10):3059-3066. doi: 10.1007/s00520-017-3713-9. Epub 2017 Apr 28.
We aimed to assess the factor structure, internal consistency, test-retest reliability, and construct validity of the European Portuguese version of the Pittsburgh Sleep Quality Index (PSQI) in breast cancer patients.
This study was based on a cohort of breast cancer patients, among whom the PSQI was used to measure sleep quality three years after cancer diagnosis (N = 474). A sample of 62 participants underwent additional PSQI testing, wore a wrist actigraph for five consecutive days, and was reevaluated with the PSQI after one month. A confirmatory factor analysis, considering the components suggested by the principal component analysis (PCA), was performed to determine model fit. To evaluate internal consistency and test-retest reliability, Cronbach's alpha and intraclass correlation coefficient (ICC) were calculated, respectively. To assess construct validity, Spearman's correlation coefficients were computed between PSQI scores and actigraphy measures and other theoretical related constructs.
PCA suggested one or two components. The latter showed better fit to the data, though the two factors were strongly correlated (r = 0.76) and internal consistency was not satisfactory for one of the factors. Regarding the one-factor model, internal consistency (Cronbach's alpha = 0.70) and test-retest reliability (ICC = 0.76) were adequate. Sleep duration, habitual sleep efficiency, and sleep disturbance dimensions were significantly correlated with the corresponding actigraphy measures; the PSQI global score derived from the one-factor model was more strongly correlated with subjective sleep complaints (r ≥ 0.60).
The unidimensional construct of the European Portuguese version of the PSQI showed adequate reliability and validity among breast cancer patients.
本研究旨在评估欧洲葡萄牙语版匹兹堡睡眠质量指数（PSQI）在乳腺癌患者中的结构因素、内部一致性、重测信度和构念效度。
本研究基于乳腺癌患者队列，其中 PSQI 用于测量癌症诊断后三年的睡眠质量（N=474）。62 名参与者进行了额外的 PSQI 测试，佩戴腕式活动记录仪连续五天，并在一个月后用 PSQI 重新评估。进行了验证性因子分析，考虑了主成分分析（PCA）建议的成分，以确定模型拟合度。为了评估内部一致性和重测信度，分别计算了克朗巴赫α和组内相关系数（ICC）。为了评估构念效度，计算了 PSQI 评分与活动记录仪测量值和其他理论相关结构之间的 Spearman 相关系数。
PCA 建议使用一个或两个分量。后者与数据拟合得更好，尽管两个因素高度相关（r=0.76），并且一个因素的内部一致性不理想。对于单因素模型，内部一致性（克朗巴赫α=0.70）和重测信度（ICC=0.76）是足够的。睡眠持续时间、习惯性睡眠效率和睡眠障碍维度与相应的活动记录仪测量值显著相关；来自单因素模型的 PSQI 总分与主观睡眠抱怨更密切相关（r≥0.60）。
在乳腺癌患者中，欧洲葡萄牙语版 PSQI 的单维结构具有足够的可靠性和有效性。
