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Operator Performance Assessment Scale/Evidence
Method evidence record

Operator Performance Assessment Scale

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.

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Source record

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Operator Performance Assessment Scale (OPAS)
Taxonomic method record · process-pipeline / human-factors
  • Wierwille, W. W., & Eggemeier, F. T. (1993). Recommendations for mental workload measurement in a test and evaluation environment. Human Factors, 35(2), 263–281. · DOI 10.1177/001872089303500205
  • Vidulich, M. A., & Tsang, P. S. (1988). The role of output modality in performance and mental workload during concurrent spatial and verbal tasks. Human Factors, 30(5), 613–623. · URL
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Same method familyHuman Error Assessment and Reduction Techniquemachine-suggested · Relational suggestion, not evidence.Same method familyNASA Task Load Indexmachine-suggested · Relational suggestion, not evidence.Same method familySituational Awareness Rating Techniquemachine-suggested · Relational suggestion, not evidence.Same method familyWorkload Profilemachine-suggested · Relational suggestion, not evidence.

Evidence status

Sources recorded, not reviewed

Bibliographic sources are present. Claim-level evidence review has not been performed.

Sources

2 recorded citations, copied from the method source record.

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