Neuropsychological Assessment Lab Reports: Revised Norms
NEUROPSYCHOLOGICAL ASSESSMENT LAB
PAUL JONES, ED.D.
UNIVERSITY OF NEVADA, LAS VEGAS

____________________________________________________________________

REVISED NORMS:
Assessment Lab Report 3-2
June/1999

This report provides summary data on characteristic response patterns of upper division teacher education students on selected ANAM/TWB instruments, combining data from series one, series two, and series three studies. The intent is to provide baseline data for use in future studies, enhancing the capability to use the instruments in placement decisions and to isolate treatment effects. Demographic information about series one, series two, and series three participants is available in lab reports. Related reports are also available with descriptions of the test instruments used in series one, series two, and series three .

The format of this report is intended to provide sufficient detail for future investigators to replicate the test conditions. For the ANAM/TWB scales used in this test series, this report includes:

1. a description of the response conditions
2. summary statistics for accuracy and efficiency scores
3. identification of score levels which may be clinically significant

Accuracy is defined as the percentage of correct responses. Efficiency is the number of correct responses per minute. Because accuracy scores on the ANAM/TWB scales are typically high, the efficiency score is likely to be more useful in most applications.

Calculation of the clinical significance levels is based on procedures suggested by Gastaldo, Reeves, Levinson, and Wenger (1997) and by Kay (1995). Scores in the range between the 5th and 15th percentile are identified as suggesting moderate impairment. Scores below the 5th percentile are identified as suggesting significant impairment.

Normative data for the Simple 2-Choice Reaction Time scale are based on participants in the series two (n=71) and series three (n=82) studies. Support for combining these data in a single normative scale was found in that differences in performance between participants in the series was not statistically significant for either accuracy (t(151)= .46, p > .05) or efficiency (t(151)= .80, p > .05) scales.

Normative data are provided for various conditions of administration of the Procedural Reaction Time test. Participants in series one (n=52), series two (n=71), and series three (n=82) completed, as trial 1, the standard version with 37 stimuli presented with predictable time interval between each stimulus. Although practice conditions were different in the series one studies, no significant differences were found among the three participant samples in accuracy (F(2, 202)= .10, p > .05) or efficiency (F(2, 202)= 1.63, p > .05).

To assess the level of maintenance of attention over time, the series three studies followed the initial trial with four additional trials. Each of the additional trials used 37 stimuli. Trials 2 and 4 used unpredictable time intervals between stimuli; trials 3 and 5 (as in trial 1) used predictable time intervals between stimuli.

In Series one and series two studies, the initial trial of the Procedural Reaction Time test was followed by a trial in which the task demand was identical, but stimuli on the screen were visually distorted and more difficult to identify. Data from the two participant samples are combined in the norms table. No significant differences were evident between the sample groups on either accuracy (t(121)= .30, p > .05) or efficiency (t(121)= 1.51, p > .05)scores.

Data from series one and series two studies are also combined in the norms for the Mathematical Processing, Spatial Processing, and Matching to Sample scales. No significant differences were found between the participant groups in math accuracy (t(121)= .80, p > .05) or efficiency (t(121)= .61, p > .05), in spatial accuracy (t(121)= .67, p > .05) or efficiency (t(121)= 1.68, p > .05), and in accuracy (t(121)= 1.94, p > .05) or efficiency (t(121)= 1.67, p > .05) on the matching to sample test.

Normative data for the two Sternberg scales not included in the series two or series three studies are available in a series one report.

The data below are for actual test trials. In each case, the test trial has been preceded by a brief practice session.

____________________________________________________________________

SIMPLE 2-CHOICE REACTION TIME: Standard Stimuli

Stimuli are presented on the screen for up to 8000 ms with a maximum of 9000 ms allowed for response. The test trial has 30 stimuli (items).

____________________________________________________________________

TABLE 1
SIMPLE 2-CHOICE REACTION TIME
n=153
accuracy percentefficiency score
mean97.2131.8
s.d.3.9917.60
median96.7132.5
maximum100.0169.6
minimum66.762.4
75%ile100.0141.6
25%ile96.7122.3
moderate impairment90 to 93101 to 117
significant impairment0 to 890 to 100

____________________________________________________________________

PROCEDURAL REACTION TIME: Standard Stimuli

Stimuli are presented on the screen for up to 8000 ms with a maximum of 9000 ms allowed for response. The test trial has 37 stimuli (items).

____________________________________________________________________

TABLE 2
PROCEDURAL REACTION TIME-Trial 1
Predictable Time Interval Between Stimuli
n=205
accuracy percentefficiency score
mean98.0104.3
s.d.3.3612.31
median100.0105.6
maximum100.0129.1
minimum80.060.9
75%ile100.0113.0
25%ile96.796.3
moderate impairment94 to 9585 to 88
significant impairment0 to 930 to 84

____________________________________________________________________

TABLE 3
PROCEDURAL REACTION TIME-Trial 2
Unpredictable Time Interval Between Stimuli
n=82
accuracy percentefficiency score
mean97.5103.1
s.d.3.1013.50
median96.7104.9
maximum100.0133.4
minimum86.773.2
75%ile100.0113.2
25%ile96.795.3
moderate impairment90 to 9382 to 87
significant impairment0 to 890 to 81

____________________________________________________________________

TABLE 4
PROCEDURAL REACTION TIME-Trial 3
Predictable Time Interval Between Stimuli
n=82
accuracy percentefficiency score
mean97.3111.3
s.d.3.6012.34
median100.0112.6
maximum100.0139.3
minimum83.381.3
75%ile100.0120.0
25%ile96.7102.7
moderate impairment94 to 9593 to 98
significant impairment0 to 930 to 92

____________________________________________________________________

TABLE 5
PROCEDURAL REACTION TIME-Trial 4
Unpredictable Time Interval Between Stimuli
n=82
accuracy percentefficiency score
mean97.8103.7
s.d.2.8812.75
median100.0103.4
maximum100.0130.9
minimum86.772.3
75%ile100.0113.0
25%ile96.794.5
moderate impairment94 to 9583 to 89
significant impairment0 to 930 to 82

____________________________________________________________________

TABLE 6
PROCEDURAL REACTION TIME-Trial 5
Predictable Time Interval Between Stimuli
n=82
accuracy percentefficiency score
mean97.6112.0
s.d.3.6712.59
median100.0111.5
maximum100.0138.5
minimum76.782.5
75%ile100.0122.7
25%ile96.7102.6
moderate impairment94 to 9591 to 98
significant impairment0 to 930 to 90

____________________________________________________________________

PROCEDURAL REACTION TIME: Degraded Stimuli

The task demand was identical to the standard stimulus condition, but stimuli on the screen were visually distorted and more difficult to identify. Stimuli are presented on the screen for up to 8000 ms with a maximum of 9000 ms allowed for response. The test trial has 37 stimuli (items).

____________________________________________________________________

TABLE 7
PROCEDURAL REACTION TIME-Degraded Stimuli
n=123
accuracy percentefficiency score
mean98.399.4
s.d.2.7516.96
median100.0101.0
maximum100.0131.8
minimum86.750.6
75%ile100.0111.4
25%ile96.790.6
moderate impairment93 to 9566 to 80
significant impairment0 to 920 to 65

____________________________________________________________________

MATHEMATICAL PROCESSING

Math problems using sets of three single-digit numbers, e.g., 5+3-4 = ? are displayed on the screen. The subject determines whether the answer is greater than or less than five, responding by clicking the left or right mouse button. Stimuli are displayed for up to 14900 ms with 15000 ms allowed for response. The test trial has 25 stimuli (items).

____________________________________________________________________

TABLE 8
MATHEMATICAL PROCESSING
n=123
accuracy percentefficiency score
mean92.824.1
s.d.8.136.16
median96.023.6
maximum100.042.4
minimum52.09.6
75%ile100.028.3
25%ile92.019.8
moderate impairment76 to 8714 to 16
significant impairment0 to 750 to 13

____________________________________________________________________

SPATIAL PROCESSING: Simultaneous

Two histograms are displayed simultaneously on the monitor. The histogram on the right is rotated. The subject indicates with click of left or right mouse button whether the two histograms are identical in shape. Stimuli are displayed for up to 8000 ms with up to 9000 ms allowed for response. The test trial has 25 items.

____________________________________________________________________

TABLE 9
SPATIAL PROCESSING-Simultaneous
n=123
accuracy percentefficiency score
mean92.729.8
s.d.9.287.47
median96.029.6
maximum100.052.5
minimum52.010.7
75%ile100.034.8
25%ile89.024.2
moderate impairment76 to 8719 to 20
significant impairment0 to 750 to 18

____________________________________________________________________

MATCHING TO SAMPLE

A single 4 by 4 matrix with cells of red and yellow is displayed on the screen. The subject initiates the presentation of the test stimulus by clicking a mouse button. The test stimulus consists of two 4 by 4 matrices, side by side on the screen, one of which is identical to the previously presented standard stimulus. The subject clicks the left or right mouse button to identify the identical stimulus. Stimuli are displayed for up to 14900 ms with 15000 ms allowed for response. The test trial has 25 items.

____________________________________________________________________

TABLE 10
MATCHING TO SAMPLE
n=123
accuracy percentefficiency score
mean88.932.2
s.d.9.769.74
median92.031.2
maximum100.062.9
minimum56.011.4
75%ile96.037.1
25%ile84.025.2
moderate impairment68 to 7518 to 22
significant impairment0 to 670 to 17

____________________________________________________________________

References

Gastaldo, E., Reeves, D., Levinson, D., & Wenger, C.B. (1997). ANAM normative data: USMC-1995 hyponatremia outbreak studies. San Diego, CA: National Cognitive Recovery Foundation.

Kay, G. (1995). Cogscreen: Aeromedical edition: professional manual. Odessa, FL: Psychological Assessment Resources, Inc.

____________________________________________________________________

SERIES THREE STUDIES

Guide to Reports

____________________________________________________________________

|Return to Jones Home Page| |Return to Department Faculty| |Return to Educational Psychology Department|