IQ testing for adults with ADHD: which test to take, what it shows and why one score is not enough

0 The short answer

No IQ test is built for adults with ADHD and none can diagnose or rule out ADHD, so the useful choice is a normed adult battery that reports working memory and processing speed apart from reasoning, read as a profile and not as one number. A 2006 meta-analysis of adults found a small Full Scale IQ gap that the authors called not clinically meaningful, while a study of 116 adults with ADHD found, relative to matched controls, weaker working memory and processing speed subtests and a General Ability Index above the Full Scale IQ. ACIS is one option, a normed online battery at 15, 30 or 50 dollars (read October 28, 2026), about 45 to 175 minutes, with a free trial that needs no card; it is not a clinical instrument, not a diagnosis and not for accommodations.

1 Is There an IQ Test Made for Adults With ADHD, and What Is This Page For?

There is no IQ instrument designed for adults with ADHD, and the useful question is which existing assessment fits the reason you want a number. A search for "IQ test for adults with ADHD" on October 28, 2026 returned research summaries, explainers and commercial articles, and it returned no instrument built for this group. That is expected. A published IQ test compares a person with a defined adult reference group, and an adult with ADHD takes the same battery as any other adult. What differs is how the result is read, which is the subject of this page.

The page is written for adults, whether diagnosed, waiting for an assessment, wondering, or simply curious how their abilities compare. ACIS norms cover ages 16 to 90, and a reader under 16 is better served by a school psychologist than by a website. The research overview on ADHD and intelligence covers what ADHD is and is not, and this page does not repeat it. Here the question is practical: what to take, what it costs, what the research says a score pattern can and cannot mean, and how to set up a fair session.

Adults ask for an IQ test for four different reasons, and each leads to a different route. The first is curiosity, a wish to see measured reasoning, memory and speed on one report, which fits a normed online test. The second is a wish to understand a diagnosis already made, where a profile can describe strengths and weaknesses but cannot confirm or revise the diagnosis. The third is an ADHD assessment itself, which belongs to a qualified clinician. The Centers for Disease Control and Prevention page on diagnosing ADHD, last reviewed October 21, 2026, states that there is no single test to diagnose ADHD, and it says the diagnosis can be made by a mental health professional or by a primary care provider. That page describes the steps for children and gives no adult procedure, so the adult process should be confirmed with the clinic or service that will do the evaluation. The fourth reason is documentation for work or study accommodations, and an unsupervised online IQ test is not designed to supply that.

2 Which Tests Can an Adult With ADHD Take, and What Does Each Cost?

The routes run from free to 2,100 dollars at the university clinics we read, and only some of them return an IQ score at all. The table sets the routes side by side with the prices and details we read on October 28, 2026. The two university clinics named are examples of how clinical evaluations are priced, not a survey, and a clinic near you may charge differently or offer a different service. When a page did not state a detail, the cell says so.

Two points from the table matter for this reader. First, the supervised routes are clinical evaluations, and the Pearson product page for the WAIS-5 describes a test sold with a qualification level, an age range of 16 to 90 and its own General Ability Index and Cognitive Proficiency Index. The CU PATH page and the University of Alabama clinic page show what an evaluation costs at two university clinics; neither itemizes the tests. Second, only the last row is a normed battery you can take at home today. The guides on where to take an IQ test and how an adult IQ evaluation works, with its cost and wait cover the in person routes in detail, and the guide to neuropsychological testing for adults covers the wider battery.

3 What Do IQ Tests Show in Adult ADHD Groups?

Meta-analyses find that ADHD groups average lower than comparison groups on Full Scale IQ, that the gap in adults is small, and that the same groups also differ on working memory and other tasks, but a group average describes no individual. An early synthesis, Frazier, Demaree and Youngstrom (2004), compared ADHD and healthy participants on common intellectual and neuropsychological measures. Its abstract reports a weighted effect size of 0.61 for Full Scale IQ, smaller than the effects for spelling and arithmetic achievement tests and comparable to most other measures, and the authors conclude that overall cognitive ability is lower among persons with ADHD on average. The abstract does not report adults separately. On a scale with a standard deviation of 15, an effect of 0.61 standard deviations works out to about 9 IQ points (our arithmetic, not a figure the authors state, and a difference between group averages that says nothing about any one person), and the page on what a standard deviation of 15 means explains how IQ points and standard deviations relate.

The adult question has its own meta-analysis. Bridgett and Walker (2006) found 33 studies that met their criteria and based the main analyses on 18 of them, which together represented 1,031 adults with ADHD and 928 nonclinical comparison adults with Wechsler Adult Intelligence Scale Full Scale IQ scores or estimates. Adults with ADHD scored lower, and the authors describe the difference as small and not clinically meaningful. Several moderators, which reflect characteristics of the ADHD samples and study methodology, led them to suggest that only a subset of adults with ADHD, for example those with comorbid disorders, may have lower general intellectual ability than comparison adults. The reading that follows from that is cautious. An average gap can come from a few people with large differences and many with none, and the abstract cannot tell us which describes the reader.

A broader review adds the wider cognitive picture. Pievsky and McGrath (2018) summarized 34 meta-analyses, with 253 standardized mean differences, comparing people with ADHD and typically developing controls. Of the 253, 244 (96 percent) favored the control group, and the mean effect size was 0.45. Unweighted domain means ran from 0.35 for set shifting to 0.54 for working memory, with intelligence and achievement, a single combined domain, at 0.51. Two moderators are worth knowing: differences were greater among children and adults than among adolescents, and meta-analyses that received drug funding found larger effect sizes than those without it. The second finding is a reason to read the size of any single ADHD effect with some caution, without treating the direction as in doubt.

The limit that matters most is built into the nature of a group mean. The Standards for Educational and Psychological Testing (American Educational Research Association, American Psychological Association and National Council on Measurement in Education, 2014), in the comment to Standard 10.6 in its chapter on psychological testing, state that differences between group means and their statistical significance give inadequate information on validity for individual diagnostic purposes, and they name effect sizes and the overlap between distributions among the additional information that might be considered. An effect near 0.5 standard deviations leaves the two distributions overlapping across most of their range, so a person with a given score could belong to either group. The page on what IQ measures and what it leaves out sets the same caution for any single number.

4 Why Do Working Memory and Processing Speed Score Lower in ADHD Groups?

The adult WAIS-IV case control study we verified found decrements in the ADHD group on subtests with working memory and processing speed demands, and its authors read those decrements as the most likely reason the group's Full Scale IQ sat below its General Ability Index. Theiling and Petermann (2016) assessed 116 adults with ADHD and 116 randomly matched controls aged 16 to 71. Relative to controls, the adults with ADHD showed significant decrements on subtests with working memory and processing speed demands, with moderate to large effect sizes, and a higher General Ability Index than Full Scale IQ. The authors conclude that a reduction of the Full Scale IQ is most likely due to a decrement in working memory and processing speed. That is their interpretation of a group pattern in one clinical sample, and it is not a statement about any reader's profile.

The Cattell-Horn-Carroll model separates the two abilities by name. Working memory (Gwm) is the capacity to hold information in mind and work on it, and processing speed (Gs) is the efficiency of simple, overlearned operations under time pressure. The formats that sample them are simple to describe without reproducing any item. Digit Span samples immediate auditory-verbal storage and, in harder versions, reordering, and its items are presented as audio. Alphanumeric Sequencing asks a person to hold a mixed stream of letters and numbers, separate the two classes and reorder each by a rule. Visual Sequence samples temporary storage for ordered visual or spatial material, the territory the guide to the visual memory test explores from the visual side. Coding asks for quick symbol conversion with a key, and Symbol Search asks for quick visual comparison of target and search sets. The page on how working memory is tested in adults and the guide to the normed processing speed index describe the two domains as wholes, and the page on why processing speed is the domain that changes first with age explains why speed scores are always read against age peers.

The ACIS pages say plainly that performance on these tasks can depend on attention control, sequencing and resistance to interference, and that Coding is read with caution because speed, attention, motor fluency, visual efficiency and comfort with timed performance can all matter at once. That is the core interpretive difficulty for this reader. A span task or a timed task is sensitive to attention as well as to the ability it names, so a lower score cannot by itself say whether the ability, the attention at that moment or both were different. The APA Guidelines for Psychological Assessment and Evaluation (American Psychological Association, 2020) state in the rationale for Guideline 9, on cultural competence, an aim that applies here too: every person assessed should have an opportunity to demonstrate their standing on the talents, capacities and traits being assessed without being impeded by construct irrelevant sources.

One more finding keeps the pattern in proportion. Ko and colleagues (2022) compared 45 patients with bipolar I disorder and 46 healthy controls on the WAIS-IV and reported poorer performance in subtests and indexes that reflect working memory and processing speed, with generalized ability, including verbal comprehension and most perceptual reasoning skills, remaining intact. A pattern of weaker working memory and speed beside intact reasoning therefore appears in more than one condition, and it cannot point to ADHD on its own. The sibling guides on the IQ test for autistic adults and the dyslexia friendly IQ test take up how to read a profile for two other groups of readers, and the guide to the IQ profile test explains how to read an uneven profile in general.

5 What Are the General Ability Index and the Cognitive Proficiency Index, and Which Should an Adult With ADHD Read?

The General Ability Index summarizes reasoning and knowledge without working memory and processing speed, the Cognitive Proficiency Index summarizes those two together, and reading both beside the Full Scale IQ shows whether one side is pulling the headline number. Campbell, Rossini and Johnson (2025) describe how the WAIS-IV assigns its ten standard subtests to one of two constructs, the General Ability Index or the Cognitive Proficiency Index, and that the Cognitive Proficiency Index is composed of the two working memory subtests and the two processing speed subtests (Digit Span, Arithmetic, Coding and Symbol Search). The abstract says the index is inferred to be a non-intellective measure of information processing efficiency. The other six standard subtests make up the General Ability Index (our arithmetic: ten minus four). The Pearson page for the WAIS-5, opened for this guide, lists both a General Ability Index and a Cognitive Proficiency Index among that test's scores, so the pair belongs to the current edition of that test.

For this reader the pair matters because of the Theiling and Petermann result: in the ADHD group the General Ability Index came out higher than the Full Scale IQ. The Full Scale blends all the subtests, so a group that is weaker on four of them (in the WAIS-IV, the four that make up the Cognitive Proficiency Index) tends to have a lower blend than its reasoning scores alone would give. The page on the General Ability Index sets out how the composite is built and why it is not a corrected score: working memory and processing speed are part of general ability, and leaving them out changes the question the composite answers instead of removing error. The sensible reading is therefore two numbers, with neither crowned as the true IQ. The technical manual lists both composites among those ACIS can report, and describes the Cognitive Proficiency Index as one that "combines working memory and processing speed as cognitive proficiency". Which composites a form returns depends on the subtests it contains, because the manual says they are available when their subtests are.

A gap between the two composites is common enough to need care. Ryan and colleagues (2018) examined the WAIS-IV General Ability Index and Cognitive Proficiency Index in 42 people with multiple sclerosis and 47 with traumatic brain injury. In both samples the mean pattern was a General Ability Index above the Cognitive Proficiency Index, which occurred in 61.9 percent and 78.7 percent of individual protocols, and the discrepancy score, used to tell the two samples apart, reached an area under the curve of 0.67, which the authors describe as low accuracy in group classification. The same uneven shape therefore shows up in people with other conditions, and the page on how common large index score differences are reports WAIS-IV simulation work in which large gaps between some pair of indices were common among typical individuals.

6 Can an IQ Test Diagnose ADHD or Rule It Out?

No: an IQ score is not a diagnostic test for ADHD, a typical or even strong profile does not rule ADHD out, and a weaker working memory or speed score does not establish it. Four lines of evidence agree. The first is the plain statement from the CDC, in the page on diagnosing ADHD last reviewed October 21, 2026, that there is no single test to diagnose ADHD. The second is the structure of the research above: the studies compare group averages, and the Standards for Educational and Psychological Testing say such differences inadequately support individual diagnosis. The third is the overlap shown by Ryan and colleagues and by Ko and colleagues, where the same working memory and speed shape appears in other conditions. The fourth is the Bridgett and Walker suggestion that only a subset of adults with ADHD may have lower general ability at all.

The Standards are specific about how test results should enter a diagnosis. Standard 10.6 says that when differential diagnosis is needed, the professional should choose, if possible, tests with credible evidence that scores distinguish between the diagnostic groups of concern, rather than merely telling clinical cases apart from the general population. Standard 10.15 says the interpretation of test or battery results for diagnostic purposes should rest on multiple sources of test and collateral information and on an understanding of the normative, empirical and theoretical foundations and the limitations of the tests, and its comment notes that a pattern of test performance is a cross sectional view of a person in a particular context. Guideline 7 of the APA guidelines makes the same point in plainer words: individual performance on a psychological test is one piece of an assessment, combined with interviews, other sources and records.

That is why cognitive measures sit inside clinical assessments instead of replacing them. The opening sentence of the Frazier abstract notes that cognitive measures are used frequently in the assessment and diagnosis of ADHD, and the clinical use is as one input among several that a qualified professional weighs. For a reader, the practical reading is two sided. A typical profile is no reason to dismiss ongoing difficulties, and an uneven profile is no reason to conclude that ADHD is present. If you are asking whether you have ADHD, the person to ask is a qualified clinician, and the guide to neuropsychological testing for adults explains what a wider evaluation can include.

7 Does ADHD Medication Change IQ Test Results?

The medication evidence we could verify reports reaction time, attention, inhibition and working memory outcomes and not Full Scale IQ, so it supports no claim that a medicated or an unmedicated IQ score is the truer one. The synthesis we could verify is Isfandnia, El Masri, Radua and Rubia (2024), a meta-analysis of the longer term effects of methylphenidate (20 studies, minimum one week) and atomoxetine (8 studies, minimum three weeks) in ADHD. The authors point out that earlier meta-analyses of stimulant effects on cognition mostly tested single doses. Their outcomes were reaction time, attention, inhibition and working memory. For methylphenidate, 18 studies with 1,667 participants showed performance better than placebo in all of those domains, with small to medium effect sizes (Hedges g of 0.34 to 0.59). For atomoxetine, 7 studies with 829 participants showed no effect on working memory and medium to large effects on the other domains (0.36 to 0.64). The abstract does not break the participants down by age, so these findings cannot be assumed to describe adults alone.

Three limits keep that result in proportion. The outcomes are those four domains, and the abstract reports no Full Scale IQ. The comparison is medication against placebo in controlled studies, which is a different question from how one person's score on a home test compares across two sittings. And in the searches we ran for this page we found no verified meta-analysis of Full Scale IQ in adults tested on and off medication, so this page makes no claim about what a medicated IQ score looks like.

A second source covers a different group. Marraccini, Weyandt, Rossi and Gudmundsdottir (2016) pooled studies of prescription stimulants in healthy adults, so not adults with ADHD, and reported a positive influence on the accuracy of processing speed tasks (g of 0.282, 95 percent confidence interval 0.077 to 0.488, 345 participants). They found neither improvement nor impairment for planning, decision making or perseveration, and note that few studies examined those outcomes. That result describes healthy adults and an accuracy outcome. It does not show what a prescribed stimulant does to an adult's score on a speed subtest, and this page does not suggest that anyone take a stimulant to change a test score.

Repeated testing adds a further confound for any comparison of two sittings. Scharfen, Peters and Holling (2018) meta-analyzed 174 samples from 122 studies and found significant retest effects, with no further score gains after the third administration, and moderators that included the retest interval and whether the test forms were equivalent. Two sittings of the same battery, one on and one off medication, therefore mix any medication effect with the retest effect, and the order of the sittings alone can change the comparison. A comparison planned by a clinician can account for that; two sittings at home cannot.

Whether to take or skip a prescribed medication on any test day is a decision for the prescriber, and this page does not recommend either. Nothing here suggests changing a prescription to take a test. What the Standards do support is documenting the context. Standard 10.12 of the Standards for Educational and Psychological Testing asks that interpretation consider other factors that may influence a testing outcome, and its comment lists health status, current mental state and the testing situation among them. If you test at home, note the date, the time of day, how you slept and whether you had taken your prescribed medication that day, and give those notes to whoever helps you read the result.

8 How Should an Adult With ADHD Set Up an Unsupervised Online Test?

An unsupervised session cannot control the room for you, so the fairest setup is a protected block of time, working sound, one device and the same conditions across sessions, with breaks placed between subtests and not inside timed tasks. The Standards for Educational and Psychological Testing explain why conditions matter. Standard 10.8 asks professionals to follow administration instructions and to provide settings that facilitate the performance of test takers, and its comment notes that the normative data were collected under standard procedures, so any nonstandard procedure can change the score and its interpretation. The comment to Standard 10.9 adds that the person interpreting scores should be told when a test was unproctored. Guideline 8 of the APA guidelines says adhering to standardized conditions minimizes confounds that lead to misreading results. An online test at home is unproctored by design, so the standard conditions are yours to supply.

The ACIS test gives you room to arrange a calm session. Breaks are allowed, progress is saved between subtests and you have 30 days to complete a form, so a 175 minute Full Scale form does not have to be one sitting. Splitting it across days, with each break between subtests, is allowed by that design. Inside a subtest the clock is part of the measure: the Coding page names resistance to small errors under time pressure as part of the demand and the Symbol Search page names decision speed as a main demand, so extra time or a pause there changes what is being measured. The pages do not describe adjusted timing, and this page does not assume any. Formal accommodations are a matter for a clinical evaluation, not for a website.

• Protect the block. Put the subtests you will do in a window you can keep quiet, and close other tabs and applications on the device.
• Remove the phone. Put your phone out of reach and silence notifications. A buzzing phone is part of the testing situation, which the comment to Standard 10.12 lists among the factors that may introduce construct irrelevant variance.
• Check the sound. Digit Span, Alphanumeric Sequencing and Arithmetic present their items as audio and need working sound, so test your speakers or headphones before you start.
• Keep the setup the same. Use the same device and room across sessions, so differences between subtests are not differences in setup.
• Take breaks between subtests. Stop after a subtest when you need to, not partway through one.
• Record the context. Note the date, time of day, sleep and anything else that bears on the session, as the previous section describes.
• Read English comfortably. ACIS is in English only, and the technical manual says verbal and knowledge tasks are affected by English proficiency and educational exposure.

9 How Should an Adult With ADHD Read the Score?

Give the most weight to the numbers built from the most tasks, the Full Scale IQ and the indexes, read single subtest scores with caution, look at every score with its confidence interval, and treat any gap between two numbers as a question for a professional and not as a finding. ACIS reports indexes and the Full Scale IQ on the standard scale, with a mean of 100 and a standard deviation of 15, and scaled subtest scores from 1 to 19 with a mean of 10 and a standard deviation of 3, plus percentiles and a 95 percent confidence interval. The page on how IQ scores are normed explains what the reference group is, and the page on why an IQ score and a percentile cannot be averaged explains why the two are never mixed.

The reason for that weighting is the structure of measurement, which the Standards for Educational and Psychological Testing state in general terms. In their chapter on reliability and precision, shortening an assessment is likely to lower its reliability, and lengthening it with comparable tasks is likely to raise it, so a score built from many tasks is steadier than one built from a single task. The same chapter says reliability estimates for total scores are not sufficient when subscores are interpreted, and that when interpretation centers on the peaks and valleys of a profile, the reliability of the score differences is critical. That is the caution for this reader: a gap between working memory and reasoning is an interesting observation, and it is also a difference between two scores that each carry error. The page on reliability and validity explains the terms without reference to any one test.

Two habits help. Read the confidence interval before the point score, because a Full Scale IQ of 108 with a wide interval is a range and not a number. And compare yourself with the adult reference group the test was normed on, never with the ADHD group averages in this page. Those averages came from other people in other samples, and the comment to Standard 10.6 says differences between group means give inadequate information about validity for individual diagnostic purposes. For where a score sits against the population, an IQ percentile calculator converts a standard score to a percentile.

10 Which ACIS Subtests Cover Working Memory and Processing Speed, and What Does the Free Trial Include?

ACIS covers working memory with Digit Span, Alphanumeric Sequencing and Visual Sequence and processing speed with Symbol Search and Coding, and a free trial started from the Full Scale form opens exactly those five subtests with no card. Those two domains are reported as the working memory index (WMI) and the processing speed index (PSI), apart from the verbal comprehension, fluid reasoning, quantitative reasoning and visual spatial indices, so an adult who unlocks a form with reasoning subtests can see them beside reasoning on one report. The facts below were read on the published site on October 28, 2026, and prices can change.

Every form reports a Full Scale IQ with its 95 percent confidence interval, and there is no subscription. Breaks are allowed, progress is saved between subtests and you have 30 days to finish. At 10 subtests in a Custom Test the Full Scale form costs the same. The free trial is limited to one per person: the site refuses a second trial from the same email address or the same browser, and finished trial subtests are kept if you later unlock a form that includes them. The five trial subtests are Digit Span, Alphanumeric Sequencing, Visual Sequence, Coding and Symbol Search. The page on the free IQ test explains what the free option covers more generally.

The technical manual lists composites built from predefined sets of subtests, available when their subtests are, among them a General Ability Index and a Cognitive Proficiency Index that "combines working memory and processing speed as cognitive proficiency". That is the pair the research in this page points to. For an adult whose main question is how working memory and speed compare with reasoning, the Quick form cannot answer it, because it has no speed subtest. The Optimized and Full Scale forms include both speed subtests and the working memory pair of Digit Span and Alphanumeric Sequencing, and the Full Scale form adds Visual Sequence and the full reasoning set. The guide to taking an IQ test as an adult lays out how those forms compare for a general reader, and the technical manual holds the documentation behind the scores.

The example reports, linked in the boxes on this page, let you see a finished report before paying. The trial is not a diagnostic screen and does not return a diagnosis.

11 Giftedness, Late Diagnosis and Other Questions a Score Cannot Answer

An IQ profile can describe how an adult performs across abilities in one sitting, but it cannot say whether ADHD is present, whether a high score is concealing difficulty, or whether a lower index comes from ADHD, anxiety, sleep or something else. The adult meta-analysis found a small average gap in Full Scale IQ, which the authors called not clinically meaningful, and suggested that a lower general score may be concentrated in a subset, for example adults with comorbid disorders. The group averages therefore leave room for adults with ADHD across the range of measured ability, which is the position the research overview of what ADHD does and does not do to measured IQ takes. A person whose profile sits comfortably in the average or high range has not shown that attention is easy, and a person whose profile is uneven has not shown that attention is the cause.

Adults who suspect ADHD late in life may bring a different question: whether years of coping hid it. An IQ score cannot settle that. What the Standards for Educational and Psychological Testing say about interpretation applies directly: Standard 10.12 asks that an interpretation consider other factors that may influence a result, which its comment gives as including health status, current mental state and the testing situation, and Standard 10.15 asks that diagnostic interpretation rest on multiple sources of information. A history, observer reports and a clinical interview carry what a timed battery cannot.

A related question is giftedness alongside a disability. The guide to twice exceptional adults covers high ability alongside a disability, and the guide to the gifted test for adults covers how to confirm where you stand in the upper range. An uneven profile is not a failed profile: index scores are read as a set, and spread across indices is common, as noted earlier. If the aim is documentation, for example for study or work accommodations, the route is a clinical evaluation and not an online test, and that fits Guideline 6 of the APA Guidelines for Psychological Assessment and Evaluation, which asks psychologists to choose measures that are fair and appropriate for the evaluation purpose, population, setting and context.

12 Where ACIS Sits, and What a Buyer Should Do

ACIS is a normed online battery that reports working memory and processing speed apart from reasoning, and it is not a clinical instrument, not a diagnosis and not evidence for accommodations. Its limits are plain. It is online and unsupervised, which the Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014) treat as a condition that the person interpreting scores should know about. It is available in English only, and the technical manual says verbal and knowledge tasks are affected by English proficiency and educational exposure. It is not for hiring, for school accommodations or for admission to high IQ societies. This page cites no study of ACIS in ADHD groups. Where no validity studies exist for a relevant population, the Standards say interpretations should be qualified and presented as hypotheses and not as conclusions, and that is how a profile from any online test should be held, ACIS included. The APA Guidelines for Psychological Assessment and Evaluation make the same point from the other side: a test result is one piece of an assessment.

What it offers is concrete. The prices are one time, 15, 30 or 50 dollars, with no subscription. The free trial needs no card and opens the five working memory and speed subtests. The refund terms are quoted exactly as published: "Full refund within 5 days if the report does not deliver the features described at checkout or a technical issue prevents you from accessing your results." That is a conditional guarantee and not an unconditional money back promise, so read the conditions before you pay.

What a buyer should do depends on the reason:

1. If you are curious about your profile, start the free trial, take the five subtests in a quiet session, then decide whether the Optimized or Full Scale form is worth it for the reasoning side of the picture. Read the General Ability Index and the Cognitive Proficiency Index beside the Full Scale IQ, and read the confidence interval before the number.
2. If you want to know whether you have ADHD, book a qualified clinician. An ACIS report is not a screen, and it should not be used to talk yourself in or out of an evaluation.
3. If you need accommodations or documentation, the route is a clinical evaluation. Share an ACIS profile only as a conversation starter, and only if you wish to.
4. If you take any prescribed medication, follow your prescriber's plan, which this page does not alter, and note the conditions of each session as described above.

13 Sources Behind This Page

Every third party fact and figure on this page comes from the documents below, opened or verified on October 28, 2026, and any figure we derived ourselves is labeled in the text as our arithmetic. Prices and policies on clinic and publisher pages change, so check the page before you pay. The ACIS facts come from the published site and the technical manual as read on October 28, 2026.

1. American Educational Research Association, American Psychological Association, and National Council on Measurement in Education (2014). Standards for Educational and Psychological Testing. Washington, DC: AERA. Open access edition read in full text on October 28, 2026: https://www.testingstandards.net/open-access-files.html
2. American Psychological Association (2020). APA Guidelines for Psychological Assessment and Evaluation. Approved by the APA Council of Representatives, March 2020. https://www.apa.org/about/policy/guidelines-psychological-assessment-evaluation.pdf
3. Frazier, T. W., Demaree, H. A., and Youngstrom, E. A. (2004). Meta-analysis of intellectual and neuropsychological test performance in attention-deficit/hyperactivity disorder. Neuropsychology, 18(3), 543 to 555. https://doi.org/10.1037/0894-4105.18.3.543
4. Bridgett, D. J., and Walker, M. E. (2006). Intellectual functioning in adults with ADHD: A meta-analytic examination of full scale IQ differences between adults with and without ADHD. Psychological Assessment, 18(1), 1 to 14. https://doi.org/10.1037/1040-3590.18.1.1
5. Theiling, J., and Petermann, F. (2016). Neuropsychological profiles on the WAIS-IV of adults with ADHD. Journal of Attention Disorders, 20(11), 913 to 924. https://doi.org/10.1177/1087054713518241
6. Pievsky, M. A., and McGrath, R. E. (2018). The neurocognitive profile of attention-deficit/hyperactivity disorder: A review of meta-analyses. Archives of Clinical Neuropsychology, 33(2), 143 to 157. https://doi.org/10.1093/arclin/acx055
7. Isfandnia, F., El Masri, S., Radua, J., and Rubia, K. (2024). The effects of chronic administration of stimulant and non-stimulant medications on executive functions in ADHD: A systematic review and meta-analysis. Neuroscience and Biobehavioral Reviews, 162, 105703. https://doi.org/10.1016/j.neubiorev.2024.105703
8. Marraccini, M. E., Weyandt, L. L., Rossi, J. S., and Gudmundsdottir, B. G. (2016). Neurocognitive enhancement or impairment? A systematic meta-analysis of prescription stimulant effects on processing speed, decision-making, planning, and cognitive perseveration. Experimental and Clinical Psychopharmacology, 24(4), 269 to 284. https://doi.org/10.1037/pha0000079
9. Scharfen, J., Peters, J. M., and Holling, H. (2018). Retest effects in cognitive ability tests: A meta-analysis. Intelligence, 67, 44 to 66. Abstract read on October 28, 2026. https://doi.org/10.1016/j.intell.2018.01.003
10. Campbell, C. E., Rossini, E. D., and Johnson, M. S. (2025). The Wechsler Adult Intelligence Scale-IV Cognitive Proficiency Index: Alternate form reliability of the nine possible subtest tetrads. Applied Neuropsychology: Adult, 32(1), 37 to 39. https://doi.org/10.1080/23279095.2022.2146505
11. Ryan, J. J., Kreiner, D. S., Glass Umfleet, L., Gontkovsky, S. T., and Myers-Fabian, A. (2018). WAIS-IV GAI and CPI discrepancies in multiple sclerosis and traumatic brain injury. Applied Neuropsychology: Adult, 25(1), 51 to 56. https://doi.org/10.1080/23279095.2016.1241786
12. Ko, H., Park, D., Shin, J., Yu, R., Ryu, V., and Lee, W. (2022). Cognitive profiles in bipolar I disorder and associated risk factors: Using Wechsler adult intelligence scale-IV. Frontiers in Psychology, 13, 951043. https://doi.org/10.3389/fpsyg.2022.951043
13. Centers for Disease Control and Prevention. Diagnosing ADHD, last reviewed October 21, 2026, read October 28, 2026. https://www.cdc.gov/adhd/diagnosis/index.html
14. Pearson Assessments. Wechsler Adult Intelligence Scale, Fifth Edition (WAIS-5), product page read October 28, 2026. https://www.pearsonassessments.com/en-us/Store/Professional-Assessments/Cognition-%26-Neuro/Wechsler-Adult-Intelligence-Scale-%7C-Fifth-Edition/p/P100071002.html
15. University of Colorado Boulder, CU PATH clinic. Adult ADHD and learning disability evaluations, read October 28, 2026. https://www.colorado.edu/clinicalpsychology/clinics/cu-path
16. University of Alabama Psychology Clinic. Adult Assessment and Testing, read October 28, 2026. https://psychologyclinic.ua.edu/services/adult/

14 Frequently Asked Questions