Results
In this research investigation, the total number of participants was 1,789 students. Of the five groups of students whose scores were analyzed in this study, the largest group consisted of 702 students with listening disorders, with the second largest group being 605 students with a label of Other Health Impaired. The fewest participants were in the group of students with a label of Muscular Dystrophy (
n = 275). For these five groups of students, students with muscular dystrophy obtained the highest scores on the Performance IQ (
M = 92.66) and the lowest scores on the Full Scale IQ (
M = 70.12). Readers are referred to Table 1 for the descriptive statistics concerning the IQ test scores.
Regarding the normality of the three IQ scores analyzed in this study, the standardized skewness coefficients (i.e., skewness divided by the standard error of skewness) and the standardized kurtosis coefficients (i.e., kurtosis divided by the standard error of kurtosis) were all within the range of +/- 3 (Onwuegbuzie&Daniel, 2002). With all standardized coefficients being within the +/- 3 range, students’ performance on the three IQ measures were determined to be normally distributed. Readers are referred to Table 2 for the standardized coefficients concerning normality of the IQ test scores.
Finally for the last three research questions, the scores of girls and boys were compared. Both girls and boys performed below the average score on the IQ measure (
M = 100). Girls scored higher than boys on the Verbal IQ, the Performance IQ, and on the Full Scale IQ. The difference between girls and boys was greatest on the Verbal IQ, where boys outperformed girls by 13 points, and lowest on the Performance IQ, where girls only outperformed boys by 2 points. Readers are referred to Table 3 for the descriptive statistics for the three IQ measures by gender.
References
Onwuegbuzie, A. J.,&Daniel, L. G. (2002). Uses and misuses of the correlation coefficient.
Research in the Schools, 9 (1)
, 73-90.
To be compliant with APA 6th edition, students and faculty are to be aware that Table titles are placed "above" the table entry. Titles here are placed below the tables because of special formatting templates and for conciseness of visual presentation.
Descriptive Statistics for Student IQ Scores
Cognitive Measure |
M |
SD |
Full Scale IQ |
77.73 |
13.54 |
Verbal IQ |
77.97 |
13.66 |
Performance IQ |
81.14 |
14.01 |
Standardized Skewness Coefficients and Standardized Kurtosis Coefficients for Students’ IQ Scores
Cognitive Measure |
Standardized Skewness Coefficient |
Standardized Kurtosis Coefficient |
Full Scale IQ |
-1.28 |
0.89 |
Verbal IQ |
2.03 |
0.76 |
Performance IQ |
-0.99 |
0.55 |
Descriptive Statistics for Cognitive Scores by Gender
|
Boys |
Girls |
Cognitive Measure |
M |
SD |
M |
SD |
Full Scale IQ |
69.52 |
15.21 |
85.88 |
3.34 |
Verbal IQ |
90.12 |
18.91 |
76.99 |
23.03 |
Performance IQ |
87.99 |
23.65 |
89.12 |
44.31 |
Descriptive Statistics for Cognitive Scores by Gender
Output from spss
Tables 4, 5, and 6 below came directly from SPSS output. As such, they are not compliant with APA
6th edition and should not be used in theses, dissertations, or manuscripts. Only Tables 1, 2, and 3above the Output from SPSS are compliant with APA format.
Disability group membership
Frequency |
Percent |
Valid Percent |
Cumulative Percent |
Valid |
Students with Listening Disorders |
702 |
42.5 |
42.5 |
42.5 |
Students with Muscular Dystrophy |
275 |
23.3 |
23.3 |
65.7 |
Students Labeled as Other Health Impaired |
605 |
34.3 |
34.3 |
100.0 |
Total |
1789 |
100.0 |
100.0 |
Statistics
|
Wechsler Full Scale IQ 3 |
Verbal IQ |
Performance IQ (Wechsler Performance Intelligence 3) |
n |
1789 |
1789 |
1789 |
Missing |
0 |
0 |
2 |
Mean |
70.12 |
77.97 |
92.66 |
Std. Deviation |
13.541 |
13.661 |
14.005 |
Skewness |
-.279 |
.028 |
-.177 |
Std. Error of Skewness |
.071 |
.071 |
.071 |
Kurtosis |
.212 |
.142 |
.072 |
Std. Error of Kurtosis |
.142 |
.142 |
.142 |
Statistics
Gender |
Wechsler Full Scale IQ 3 |
Verbal IQ (Wechsler Verbal Intelligence 3) |
Performance IQ (Wechsler Performance Intelligence 3) |
|
Boys n |
522 |
522 |
567 |
|
Missing |
0 |
0 |
2 |
|
Mean |
79.52 |
80.12 |
82.17 |
|
Std. Deviation |
13.512 |
13.908 |
13.653 |
|
Skewness |
-.253 |
.033 |
-.217 |
|
Std. Error of Skewness |
.101 |
.101 |
.101 |
|
Kurtosis |
.374 |
.291 |
.255 |
|
Std. Error of Kurtosis |
.201 |
.201 |
.201 |
|
Girls n |
734 |
734 |
732 |
Missing |
0 |
0 |
0 |
|
Mean |
75.88 |
75.75 |
80.07 |
|
Std. Deviation |
13.339 |
13.031 |
14.307 |
|
Skewness |
-.327 |
-.046 |
-.120 |
|
Std. Error of Skewness |
.101 |
.101 |
.101 |
|
Kurtosis |
.037 |
-.084 |
-.069 |
|
Std. Error of Kurtosis |
.201 |
.201 |
.201 |
|