مقایسهٔ روش‌ها

	NASA Task Load Index	مقیاس ارزیابی عملکرد اپراتور (OPAS)
حوزه	عوامل انسانی	عوامل انسانی
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	1988	1993
پدیدآور	Sandra G. Hart & Lowell E. Staveland	William W. Wierwille, Frank T. Eggemeier
نوع	Self-report	Observer-rated / Self-rated
منبع بنیادین	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.
نام‌های دیگر	NASA-TLX, TLX	OPAS, Performance Rating Scale
مرتبط	4	4
خلاصه	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.