PDF(Pubmed)
Abstract：
Our objective was to investigate the validity of four-item and six-item versions of the National Aeronautics and Space Administration Task Load Index (NASA-TLX, or TLX for short) for measuring workload over a whole day in the repeated measures context. We analysed data on 51 people with type 1 diabetes from whom we collected ecological momentary assessment and daily diary data over 14 days. The TLX was administered at the last survey of every day. Confirmatory factor analysis fit statistics indicated that neither the TLX-6 nor TLX-4 were a unidimensional representation of whole day workload. In exploratory analyses, another set of TLX items we refer to as TLX-4v2 was sufficiently unidimensional. Raw sum scores from the TLX-6 and TLX-4v2 had plausible relationships with other measures, as evidenced by intra-person correlations and mixed-effects models. TLX-6 appears to capture multiple factors contributing to workload, while TLX-4v2 assesses the single factor of \'mental strain\'. Practitioner Summary: Using within-person longitudinal data, we found evidence supporting the validity of a measure evaluating whole-day workload (i.e. workload derived from all sources, not only paid employment) derived from the NASA-TLX. This measure may be useful to assess how day-to-day variations in workload impact quality of life among adults.Abbreviations: NASA-TLX or TLX: National Aeronautics and Space Administration Task Load Index; TLX-6: six item version of the NASA-TLX; TLX-4: four item version of the NASA-TLX, TLX-4v2: four item NASA-TLX version two; NIOSH: National Institute for Occupational Safety and Health; CFA: confirmatory factor analysis; T1D: type 1 diabetes; EMA: ecological momentary assessment; BG: blood glucose; SD: standard deviation; CV: coefficient of variation; RMSEA: root mean square error of approximation; CFI: comparative fit index; TLI: Tucker-Lewis Index; SRMR: standardized root mean square residual; AIC: Akaike information criterion; BIC: Bayesian information criterion; χ2: Chi-square statistic.
摘要：
我们的目标是调查国家航空航天局任务负荷指数（NASA-TLX，或简称TLX)，用于在重复测量上下文中测量一整天的工作负载。我们分析了51名1型糖尿病患者的数据，我们从他们那里收集了14天的生态瞬时评估和每日日记数据。在每天的最后一次调查时施用TLX。验证性因素分析拟合统计数据表明，TLX-6和TLX-4都不是全天工作量的一维表示。在探索性分析中，我们称之为TLX-4v2的另一组TLX项目是足够一维的。TLX-6和TLX-4v2的原始总和分数与其他指标有合理的关系，人内相关性和混合效应模型证明了这一点。TLX-6似乎捕获了影响工作负载的多个因素，而TLX-4v2评估“精神紧张”的单因素。从业者总结：使用人内纵向数据，我们发现了支持评估全天工作量(即来自所有来源的工作量，不仅是有偿工作）来自NASA-TLX。这项措施可能有助于评估工作量的日常变化如何影响成年人的生活质量。缩写：NASA-TLX或TLX：美国国家航空航天局任务负荷指数；TLX-6：NASA-TLX的六项版本；TLX-4：NASA-TLX的四项版本，TLX-4v2：四个项目NASA-TLX版本2；NIOSH：美国国家职业安全与健康研究所；CFA：验证性因子分析；T1D：1型糖尿病；EMA：生态瞬时评估；BG：血糖；SD：标准偏差；CV：变异系数；RMSEA：近似的均方根统计误差；CFI：比较拟合指数；TLI：Tucker-Lewis标准标准；Basis信息
