So sánh phương pháp

	NASA Task Load Index	Thang đo Đánh giá Hiệu suất Người vận hành (OPAS)
Lĩnh vực	Yếu tố con người	Yếu tố con người
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1988	1993
Người khởi xướng	Sandra G. Hart & Lowell E. Staveland	William W. Wierwille, Frank T. Eggemeier
Loại	Self-report	Observer-rated / Self-rated
Công trình gốc	Hart, S. G., & Staveland, L. E. (1988). Development of NASA-TLX (Task Load Index): Results of empirical and theoretical research. In P. A. Hancock & N. Meshkati (Eds.), Human Mental Workload (pp. 139-183). Elsevier Science Publishers.	Wierwille, W. W., & Eggemeier, F. T. (1993). Recommendations for mental workload measurement in a test and evaluation environment. Human Factors, 35(2), 263–281.
Tên gọi khác	NASA-TLX, TLX	OPAS, Performance Rating Scale
Liên quan	4	4
Tóm tắt	The NASA Task Load Index (NASA-TLX) is a multidimensional subjective workload assessment tool developed by Sandra Hart and Lowell Staveland at NASA's Ames Research Center in 1988. It measures six dimensions of cognitive and physical task load to quantify operator workload across diverse task domains, from aviation and process control to human-computer interaction. The TLX has become the gold standard for workload measurement in human factors research and applied settings.	The Operator Performance Assessment Scale (OPAS), formalized by Wierwille and Eggemeier in 1993, is a structured rating method for assessing operator task performance on multiple dimensions (primary task accuracy, secondary task accuracy, task completion time, error rate, procedure adherence) in applied settings. OPAS bridges subjective workload perception (NASA-TLX, situational awareness) and objective behavioral metrics by capturing expert judgment of performance quality across multiple performance channels, enabling holistic evaluation of how well operators managed task demands.