{"id":95,"date":"2023-10-07T19:19:15","date_gmt":"2023-10-07T19:19:15","guid":{"rendered":"https:\/\/sd5bc.info\/?p=95"},"modified":"2025-12-22T08:28:32","modified_gmt":"2025-12-22T08:28:32","slug":"are-psychologists-able-to-correctly-classify-test-scores-can-they-create-a-reasonably-accurate-frequency-table-some-can-some-cannot-and-some-do-not-want-to","status":"publish","type":"post","link":"https:\/\/sd5bc.info\/index.php\/2023\/10\/07\/are-psychologists-able-to-correctly-classify-test-scores-can-they-create-a-reasonably-accurate-frequency-table-some-can-some-cannot-and-some-do-not-want-to\/","title":{"rendered":"Are psychologists able to correctly classify test scores? Can they create a reasonably accurate frequency table? Some can, some cannot, and some do not want to."},"content":{"rendered":"\n

By Dr. Bob Uttl (October 5, 2023)<\/p>\n\n\n\n

There are three kinds of lies: lies, damned lies, and statistics.<\/p>Attributed to Benjamin Disraeli by Mark Twain<\/cite><\/blockquote><\/figure>\n\n\n\n

In her response to Ms. T’s complaint against Dr. Mary Westcott<\/a> to the College of Alberta Psychologists<\/a>, on March 29, 2021, Dr. Westcott (from Mandel & Associates Ltd.<\/a>) created a simple statistical summary of Ms. T’s scores — a frequency table titled “Summary of Ms. T’s scores obtained within my assessment”. The table gives the impression that all but three scores were “below 50th percentile” and that most scores were in “below the average range” including seven scores in the “impaired” range. Referring to the summary table she prepared, Dr. Westcott made the following misleading and false statements claims about Ms. T’s cognitive abilities and test performance:<\/p>\n\n\n\n

\n

My assessment indicated that the majority of her test scores fell below the 50th<\/sup> percentile or within the impaired range (see table below).<\/p>\n\n\n\n

Her only scores above the 50th<\/sup> percentile included word reading and verbal delayed recall.<\/p>\nDr. Westcott’s Resonse, dated March 29, 2021 (p. 12)<\/cite><\/blockquote>\n\n\n\n

Dr. Mary Westcott’s<\/a> summary table is copied below with marked-up text added in red. The red marked-up text next to various tests identifies numerous errors and falsehoods in Dr. Westcott\u2019s table. Dr. Westcott’s table shows only three columns: one for “Scores below the average range”, one for “Scores in the average range but below 50th percentile”, and one for scores above the 50th percentile. Dr. Westcott did not explain what “Below the average range” means to her but, according to WAIS-IV\/WMS-III\/IV conventions, “below average” are scores corresponding to 70-79 on IQ\/Index score scales (2 to 8th percentile or 2-8p) whereas scores below 70 IQ\/Index scores (below 2nd percentile) are “exceptionally low” or “borderline” scores. Again, we have no idea what definition of “impaired” scores Dr. Westcott had in her mind when creating her table.<\/p>\n\n\n\n

<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

<\/p>\n\n\n\n

Dr. Westcott’s table yet again demonstrates Dr. Westcott’s astonishing inability or unwillingness to accurately present and classify Ms. T’s scores:<\/p>\n\n\n\n