Research uncovers flawed IQ scoring system

March 17, 2015 by Anne Craig
The IQs of a large enough population are calculated so that they conform to a normal distribution with a mean of 100 and a standard deviation of 15. Image: Wikipedia.

Queen's University professor Allyson Harrison has uncovered anomalies and issues with the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV), one of the most widely used intelligence tests in the world. IQ scores are used to predict educational success, to help identify intellectual disabilities or intellectual giftedness and to establish whether a person has a specific learning disability.

For her research, Dr. Harrison and her colleagues examined the differences between Canadian and American WAIS-IV scores from 861 postsecondary from across Ontario. The research identified a trend where the individual's scores were consistently lower using the Canadian test scoring system. The WAIS-IV scores are used to make diagnostic decisions on the person's ability relative to their peer group.

"Looking at the normal distribution of scores, you'd expect that only about five per cent of the population should get an IQ score of 75 or less," says Dr. Harrison. "However, while this was true when we scored their tests using the American norms, our findings showed that 21 per cent of college and university students in our sample had an IQ score this low when Canadian norms were used for scoring."

The trend was the same across all IQ scores, with Canadian young adults in college or university consistently receiving a lower IQ score if the Canadian norms were used. There were fewer gifted students identified when Canadian norms were used, as well as more students who were said to be intellectually impaired.

When scoring the WAIS-IV, Canadian psychologists have the option to compare the obtained raw score with the normative data gathered in either Canada or the USA.

Dr. Harrison notes these findings have serious implications for educational and neuropsychological testing. "Research shows that you can go from being classified as average to intellectually impaired based only on whether American or Canadian norms are used to rank the obtained raw IQ score."

The research was published in the Journal of Psychoeducational Assessment.

Explore further: New method of scoring IQ tests benefits children with intellectual disabilities

More information: Journal of Psychoeducational Assessment, jpa.sagepub.com/content/early/ … 82915573723.abstract

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TopCat22
1.4 / 5 (10) Mar 17, 2015
The disturbing part is that 21% of College and University students in Canada have IQ's of 75 or less... (compared to 5% of the general population) and that some of them might be the professionals you will depend on someday in their occupation.
BONK__RS
2 / 5 (6) Mar 17, 2015
I thought it was well known that a bias is applied according to some zoning map - i know that chinese IQ tests have a couple or three points knocked off teh score and others, like the USA have a couple grafted on.
Doug_Huffman
1 / 5 (3) Mar 17, 2015
Remember, med school anchorman is still addressed as Doctor.
Gimp
3.6 / 5 (10) Mar 17, 2015
If the researcher is Canadian, can we be certain the study is correct? He or she may well be one of the college grads with a IQ of 75.
rufusgwarren
1.8 / 5 (8) Mar 17, 2015
The test should be a stupidity metric, the lessor "stupids" and the most "stupids" since intelligence is lacking in the US.
Dethe
1.8 / 5 (5) Mar 17, 2015
Of course, the sample of students can be hardly an average sample of population - even in Canada...;-) I'd don't still understand the point of the above study. It just seems for me, that the Canadian tests were developed for student cohort from their very beginning - and now everyone gets surprised with it.
TopCat22
1.2 / 5 (5) Mar 17, 2015
I think this points to a problem in the American educational systems today ... they are not designed to weed out the less competent as one would expect (... it's the opposite per this study)... They are designed to attract paying customers ... and as in all things marketed today they tend to attract a higher percentage of the more stupid to spend their money when perhaps they should not.

In many countries where education is virtually free based on academic achievement where if you are too stupid you will not get educated past high school.
Gimp
1 / 5 (2) Mar 17, 2015
So, our government giving free education to select segments of society, says what about the intelligence of the average student? If the affluent but stupid student can get a great education where does that leave the average to above average, non special sector citizen? We all know the answer but it's politically incorrect to make the correlation.
shining_genji
1 / 5 (9) Mar 17, 2015
sorry, but the explanation is obvious. Americans are smarter than Canadians, a lot smarter, it seems, or at least there are far more dumb Canadians than dumb Americans, more than four times as many.

i, for one, am not surprised.
flatusm
2.7 / 5 (7) Mar 17, 2015
There are lower percentages of low-IQ minorities (blacks, hispanics) in Canada, and more hi-IQ (Asian) minorities. This is just statistics, and supports the racial differences in IQ that no one is allowed to mention (except to discredit IQ testing!)

Canada has more asians, 7%, than blacks and hispanics combined, 4%, whereas the US has only 5% asians, but 13% blacks and 16% hispanics!

This is a huge difference which could skew the average 5 points or more!

Both countries would have to use GLOBAL norms to get the same score.
PhysicsMatter
2.7 / 5 (7) Mar 17, 2015
It was proven long time ago that IQ, SAT, GRE etc., were purposefully geared toward WASP sensibilities and aesthetics called wrongly meritocratic a replacement for strait apartheid.
Hence, it was necessary to come up with other ideas of intelligence such as EQ.
However, main issue is that we do not know what intelligence is!!! For now working hypothesis is that if one complies with authorities in politics, science, economy etc., it means he/she is intelligent, an obvious nonsense. None of people that really moved history politics or science would get even decent score on IQ, because they did not buy or submit to any standard such as measured by IQ test.
PhysicsMatter
2.6 / 5 (5) Mar 17, 2015
For real creativity one must do away with all notions what IQ test designers expect from you. It is the "submission to norms" of dominant culture and/or ruling class what is tested by IQ test. If you refuse to adopt often completely baseless notions and norms they are trying to imprint in your mind at school, you're called stupid.
adam_russell_9615
5 / 5 (7) Mar 17, 2015
sorry, but the explanation is obvious. Americans are smarter than Canadians, a lot smarter, it seems, or at least there are far more dumb Canadians than dumb Americans, more than four times as many.

i, for one, am not surprised.


I think you got this backwards. If true this indicates that the Canadian "norm" is higher.
mooster75
3 / 5 (4) Mar 17, 2015
I think you got this backwards. If true this indicates that the Canadian "norm" is higher.

Well, you couldn't have expected him to figure that out...
antigoracle
2 / 5 (4) Mar 17, 2015
I guess no one told this professor that IQ is inversely proportional to the quality of the weed.
Dug
not rated yet Mar 17, 2015
This would be the Lake Woebegon, Mist County, Mn., USA IQ test - "Where all the women are strong, all the men are good looking and all their children are above average."
Nik_2213
5 / 5 (1) Mar 17, 2015
Reminds me uncomfortably of when a mega-merger set the resulting uber-managers to evaluate the potential of their new staff-- Including us...

We politely complied with the request to do a bunch of seriously stupid tests. These documents were then fed to an automatic scanning and marking system, which promptly fell over. Yes, many of us had found umpteen logical answers that were NOT anticipated...

Seems we were rather more creative than the benighted folk who compiled those tests...
trxtgreen
1 / 5 (1) Mar 18, 2015
From the summary, all we know is that for an unknown reason the Canada WAIS is normed differently than the American WAIS. This is NOT the same thing as Canadians having a higher (or lower) average IQ than Americans, although it could be true for other reasons. If 21% of Canadians are scoring at 75 or lower, then it's unlikely to represent reality and is likely a methodological or statistical error. Because of the natural distribution of the bell curve, a score of 75 must be restricted to 5% of the population or less-- the American norms are thus likely correct. Someone wasn't paying attention when they normed the Canadian IQ test, probably.

To reach a conclusion that the Canadian IQ is higher than the American based on this study, it would also have to find that less than 5% of Canadians scored at 75 or below using American norms compared to Americans, or that more than 21% of Americans scored lower than 75 using Canadian norms compared to Canadians who scored that. It says neither.
trxtgreen
3.7 / 5 (3) Mar 18, 2015
And here's for the guy who was trying to spin it as some race thing. From the abstract:

"The differences do not appear to be due to cultural, educational, or population differences, as participants acted as their own controls."


Please leave your ideology out of this. IQ testing is a specialized subfield in Psychology that already has a checkered enough past and should only be interpreted by professionals.
Anakin
1 / 5 (2) Mar 18, 2015
@trxtgreen
Now I have the answer to why I get such high scores on tests online (+150) and lose 20-30 points when I do the usual tests when there is no average joe to compare with
I think the difference is because Americans are dumber and takes an average of the population in different countries instead of taking an average over the world.
The most frightening in this study is that Canadian students seems to be getting dumber and dumber.
If it continues, they are soon down to US levels

But we'll never Americans to accept an average of the world
adam_russell_9615
3 / 5 (2) Mar 18, 2015
I think what this actually means is that the Canadian test results do not conform to the standard bell curve. Most likely this indicates some error in the process of measurement.
gabevee
not rated yet Mar 18, 2015
Canada is on the METRIC scale... ;-)
m_darsemann
1 / 5 (2) Mar 19, 2015
This is ludicrous... Is it concerning 21% that Canadian college students are 75 or below? Not at all! As far as I know, college education is not a part of WAIS testing and the ability of new doctors for medicine is solely based on their medical performance. The artile should read: WAIS' Canadian adaptation to Canadian graduates is poorly made. Maybe the adaptation is bad or the testing is done in dobious conditions (should be done in groups), but this is no concern at all. They could have started by including the author's IQ and we wouldn't probably need to read the article to start with.
shoebox22
1 / 5 (1) Mar 21, 2015
in the past people went to university to up grade their field of study, now people go to university because they want a good job, saying that 21% of the students have 75 or below IQ gets back to some students not as good as they did in high school, now where I live in Calgary you need a 90% average to get into university and this test should also prove real life skills where students at home and all babied to do school work do not function worth a dam in secondary schooling where your out on your own and have to cook and take care of yourself ,this maybe why some students do so lousy.
Bongstar420
1 / 5 (1) Mar 21, 2015
College should be impossible for people below the IQ of 120...

I think this points to a problem in the American educational systems today ... they are not designed to weed out the less competent as one would expect (... it's the opposite per this study)... They are designed to attract paying customers ... and as in all things marketed today they tend to attract a higher percentage of the more stupid to spend their money when perhaps they should not.

In many countries where education is virtually free based on academic achievement where if you are too stupid you will not get educated past high school.


BINGO!
Morten500
not rated yet Mar 23, 2015
It's ridiculous how many commentators here have misunderstood what this research shows:

No, and a hundred times no, it does *not* show that 21% of Canadian students have an IQ of 75 or less.

In fact, it is almost the exact opposite: when using the Canadian scoring norms (instead of US scoring norms) for the WAIS, the amount of of US students scoring 75 or less increases from 5% to 21%.

This means Canadian students score significantly higher on the WAIS IQ tests than US students.

Commentator "flatusm" got it right, while a bunch of the rest of you should be ashamed.
mreda14
1 / 5 (1) Mar 23, 2015
Most text book used in college educations have solutions manual. A typical A student in the 20 century is the one who is able to get the solution manual for college text book. He knows most of the exam the professor give are from the text book. The A student study only or memorize all the solution to the chapter in the book. For example a basic physic or physical chemistry book which are used in college have solution manuals. The A student only get the solution manual and able to get an A plus in the exam. The A student do not even do the homework , he use his contact to get copy of the solution for quizzes and exam from last year and the solution manual of the book. This is the reason why the resaech publication suffers a lot of corruption.

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