0. WISC-IV VS. RIAS: Will the Real IQ Please Stand Up!!
A 2-year study comparing the two IQ instruments.

1. HYPOTHESIS
RESEARCHER HYPOTHESIZED THAT THE RIAS WOULD SCORE HIGHER GIVEN THE ADDITIONAL PSYCHOMOTOR PROCESSING AND WORKING MEMORY FACTORS ON THE WISC-IV.

2. PLEASE REFER TO THE GAI DATA AND SUPPLENTAL TABLES FOR WISC-IV UPDATES.
ADDITIONALLY, BOTH INSTRUMENTS MEASURE DIFFERENT CONSTRUCTS. THEREFORE, WE ARE MEASURING SIMILAR YET DIFFERENT ASPECTS OF COGNITION. “SQUARE FEET VS. CUBIC FEET” THINKING.

3. WISC and RIAS Verbal Comparisons
3 Subtests
General fund of knowledge
Verbal associative reasoning
Vocabulary – expressive language
Moral judgment, common sense, independent thinking
RIAS
2 Subtests
General fund of knowledge
Verbal associative reasoning
Vocabulary – one-word responses

4. WISC and RIAS Comparisons Performance IQ
3 Subtests
Nonverbal associative and categorical reasoning
Analyze and synthesize abstract visual information
RIAS
2 Subtests
Nonverbal associative and categorical reasoning
Deduce essential elements missing in pictures from gestalt

5. WISC and RIAS Comparisons – Working Memory
0 Subtests
Not part of the CIX
WISC
2 Subtests measuring attention, concentration, sequencing, and short-term auditory memory

6. WISC and RIAS Comparisons – Processing Speed
0 Subtests
Timed nonverbal tasks involving cognitive efficiency and speed w/o paper and pencil
WISC
2 Subtests
Graphomotor processing speed involving timed paper and pencil tasks
Visual-motor coordination
Concentration and visual memory

7. DESIGN Random Select Selection
Select ‘fine’ Psychologists from St. Johns County school district randomly selected students ranging from 6-16 years of age and administered both the WISC-IV and RIAS IQ instruments. All students were referred by the CST.
Abundance of data from the SY. Psychologists gave raw data to researcher to tabulate.

8. DESIGN
ONLY THE AGE OF THE STUDENTS WAS USED AS “PREDICTOR VARIABLE.” AGES RANGED FROM MAJORITY OF STUDENTS WERE IN THE 7 YR. OLD THROUGH 10 YR. OLD RANGE.

9. RACE AND GENDER NOT USED FOR COMPARISONS GIVEN LIMITED NUMBER
Only less than a handful of minority African American and Hispanics tested.
Gender not a major contributing factor on how data is to be used.

10. Pearson Correlation Coefficient
The Full Scale IQ’s and the Factor Scores will be compared to check for correlation coefficients.
WESSA.NET was used as the software program to calculate Pearson Product Moment Correlation Coefficients.

11. TOTAL N = 121 BREAKDOWN BY AGE N = Number 6 YEAR OLDS 09
___________________________________
TOTAL SAMPLE N = 121

19. Correlations Between the RIAS Index Scores and the WISC-III IQ Scores – Reynolds Manual pg. 105.
Verbal IQ
Performance IQ
Working Memory
Processing Speed
FSIQ
RIAS Index
Mean IQ
Mean IQ
108.2
104.6
------
107.8
VIX
102.1
.86
----
NIX
101.0
.33
CIX
100.3
.76

20. Perceptual Organization
Pearson Correlations Between the RIAS Index Scores and the WISC-IV Factor Scores Ages 6 – 16 (N = 121)
WISC-IV IQ
Verbal Comprehension
Perceptual Organization
Working Memory
Processing Speed
FSIQ
RIAS Index
Mean IQ
Mean IQ
96.2
95.8
89.7
90.7
92.2
VIX
99.9
.83
----
NIX
104.1
.54
CIX
101.6
.62
.45
.79

21. Perceptual Organization
Pearson Correlations Between the RIAS Index Scores and the WISC-IV Factor Scores – Primary Grade Ages 7 – 9 (N = 83)
WISC-IV IQ
Verbal Comprehension
Perceptual Organization
Working Memory
Processing Speed
FSIQ
RIAS Index
Mean IQ
Mean IQ
99.0
100.0
91.7
93.4
95.6
VIX
102.5
.83
----
NIX
105.4
.42
CIX
103.7
.58
.36
.75

22. Limitations of Study
The sample was taken from students already referred for assessment. Approximately 90% were referred for Special Needs/reevals and 10% for Gifted evaluation.
Majority of sample from 7-10 year old range. Older MS/HS population not adequately represented in sample.
Majority of sample Caucasian and from Middle Class SES. Minorities and/or Low SES not adequately represented.

23. CONCLUSIONS
RIAS tends to score approximately 10 points higher than the WISC-IV on global cognitive ability measure.
Strongest correlations between RIAS VIX and WISC-IV VC of .83 followed by RIAS CIX and WISC-IV FSIQ of .79 correlation.
Weakest link between RIAS CIX and WISC-IV PS of .45 correlation.

24. IMPLICATIONS
The range of scores among all age groups tends to favor the RIAS in regards to scoring higher on both ends of the distribution. This may influence ESE placement decisions.
Working Memory and Processing Speed tends to depress the WISC FSIQ by approximately 4 points. This may influence ESE placement decisions.
Even though RIAS scores higher on all measures and through all age groups, both instruments correlate fairly well with a high degree of confidence when comparing global IQ scores. This indicates fairly good reliability and validity.

25. FUTURE RECOMMENDATIONS
Assess minority populations and compare results with current data.
Assess Low SES w/o regard for race and compare with current data.
Assess middle and high school students to a larger extent.
Assess pre-K students with WPPSI-III and RIAS and compare data.

26. Excerpt from Dr. Cecil Reynolds e-mail …..
It is clear the difference is really in the nonverbal sections of the tests, just as we have argued for some time.  The WISC-IV in my view confounds nonverbal intelligence with a host of tangentially related factors (speed confounded with motor for example, and the differential acquiescence of kids .. to work as quickly as they can, etc.), especially for referral samples wherein you also see a far higher incidence of mild motor issues.  I think the RIAS gives a more accurate view of NV intelligence for these kids and that seems to be your conclusion as well—we do not see this difference in nonreferred samples—random samples of normal kids score at about the same level on both.     
Cecil R. Reynolds, PhD
Professor of Educational Psychology
Professor of Neuroscience