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Table 2 Descriptive statistics of individual measure performance

From: How do we measure attention? Using factor analysis to establish construct validity of neuropsychological tests

  Outcome Mean SD Min P50 Max Skewness Kurtosis Internal Reliability
Traditional Clinical neuropsychological tests          
Letter cancellation Num. correct 92.247 21.809 8 91 152 0.010 3.108 0.95
Digit symbol coding n. correct trials 55.047 13.693 16 54 116 0.861 5.371 0.93
Backward digit span Length of longest sequence 6.102 2.031 1 6 11 0.385 2.747 0.68
Forward digit Span Length of longest sequence 6.929 1.665 1 7 11 0.252 2.819 0.73
Arithmetic Points 21.231 6.019 3 22 37  − 0.300 2.730 0.85
Spatial span Span 5.423 0.970 0 5 7  − 0.720 6.268 0.58
TMT-A Resp. Time (ms) 32,517.290 18,753.160 12,168 26,579 177,934 2.599 13.347 0.95
Log(TMT-A)    − 10.273 0.456  − 12.089  − 10.188  − 9.407  − 0.792 3.511  
TMT-B Resp. Time (ms) 47,964.500 26,575.030 14,419 40,647.5 286,388 3.040 19.373 0.96
Log(TMT-B)    − 10.671 0.441  − 12.565  − 10.613  − 9.576  − 0.644 3.754  
Cognitive Psychology/experimental Paradigms          
Approximate number sense Accuracy 0.812 0.055 0.540 0.815 0.930  − 0.596 4.058 0.60
Multiple object tracking Accuracy 0.822 0.094 0.514 0.833 1.028  − 0.509 2.928 0.92
Visual working memory Number correct 34.421 4.031 20 35 42  − 0.668 3.334 0.67
Flanker interference Conflict Resp. time 0.108 0.149  − 0.833 0.083 0.917 0.760 9.334 0.85
Visual search Search slope (ms/item) 57.450 20.129  − 12.070 55.625 138.180 0.390 3.856 0.75
Gradual onset CPT d' 2.744 0.808  − 1.356 2.832 4.653  − 0.845 4.942 0.88