What the Working Memory Index combines and how to read its gaps

0 The short answer

The Working Memory Index (WMI) is a standard score built from a battery's working memory subtests, and the recipe differs by battery: Pearson pairs Digit Span with Arithmetic in the WAIS-IV, Digit Sequencing with Running Digits in the WAIS-5, and Digit Span with Picture Span in the WISC-V. ACIS reports a WMI from Digit Span, Alphanumeric Sequencing and Visual Sequence: the Full Scale form (50 dollars, about 175 minutes) holds all three, Quick (15 dollars, about 45 minutes) and Optimized (30 dollars, about 110 minutes) report a partial WMI from the first two, and the Custom Test returns the full index for the three subtests at 15 dollars (prices read October 29, 2026). The decisive limit is that a WMI cannot explain itself: an online, unsupervised, non clinical score can show that working memory sits apart from the other indices, it cannot say why, and a WMI from one battery cannot be swapped for another's.

1 What is the Working Memory Index?

The Working Memory Index is a composite score that turns performance on two or three working memory subtests into one number on the standard scale, and what that number means depends on which subtests the battery put inside it. Pearson's sample interpretive report for the WISC-V, read October 29, 2026, describes the WMI as a measure of the ability to register, maintain and manipulate visual and auditory information in conscious awareness, and adds that the task requires attention and concentration as well as visual and auditory discrimination. That wording is the publisher's definition for one battery, not a universal one, and the next sections show why the difference matters.

In the Cattell-Horn-Carroll (CHC) model, the family of abilities behind the WMI is called Gwm. The page on the CHC model lists the broad abilities and what each one covers. The ACIS Digit Span page places its task in "working memory or short-term memory capacity (Gwm/Gsm)," read October 29, 2026, which is the label to expect on any page that follows CHC naming.

The WMI is a score, so it follows the conventions of a score. Pearson's WISC-V report states that index scores sit on a standard score metric with a mean of 100 and a standard deviation of 15, and the same report calls scores from 90 to 109 typically average. The page on why the standard deviation is 15 explains what a point on that scale means. Pearson's WAIS-5 sample score report, read the same day, lays the score out in a table with the sum of the subtest scaled scores, the composite score, a percentile rank, a 95 percent confidence interval and a qualitative description, which is the report structure the rest of this page uses.

Two things the WMI is not. It is not a measure of memory in general. Remembering a conversation from last week, recalling a childhood home or learning a list of facts draw on long-term memory systems that a working memory index does not sample, and the page on IQ and memory separates those families. It is also not the ability measured by a single task: the WMI combines tasks on purpose, because one task is a narrow sample. The page on taking a working memory test covers the ability itself and the tasks that probe it, and this page stays with the index as a reported score.

2 Which subtests make up the Working Memory Index in the WAIS-5, WAIS-IV and WISC-V?

Each Pearson battery lists two primary subtests for its WMI, and the pair is different in the WAIS-5, the WAIS-IV and the WISC-V. The table is built from Pearson's own pages and score reports, read October 29, 2026. The columns separate the subtests that build the primary index from the other working memory subtests Pearson lists for the same battery.

Pearson's WAIS-5 overview brochure lists the primary index scale for working memory as Digit Sequencing and Running Digits, and lists Digits Forward, Digits Backward, Letter-Number Sequencing, Symbol Span and Spatial Addition among the working memory subtests of the full scale. Pearson's comparison flyer places the WAIS-IV beside the WAIS-5: the WAIS-IV core subtests include Digit Span and Arithmetic, Letter-Number Sequencing is supplemental, and the WAIS-5 sorts its subtests into primary and secondary tiers, with Arithmetic now secondary. The same flyer counts 4 index scores plus 1 optional index score for the WAIS-IV and 5 primary index scores plus 15 ancillary index scores for the WAIS-5. The page on the 20 WAIS-5 subtests and the page on the WAIS-IV and its index scores go through the full lists.

The adult WAIS-IV is confirmed by its score report. Pearson's WAIS-IV sample score report groups Digit Span and Arithmetic under the Working Memory heading and reports the WMI beside the Verbal Comprehension, Perceptual Reasoning and Processing Speed indices. For the child battery, Pearson's WISC-V product page names Digit Span and Picture Span as the WMI subtests and says Picture Span replaced Letter-Number Sequencing, which had contributed to the WISC-IV WMI. The WISC-V covers ages 6:0 to 16:11 and the WAIS batteries start at 16:0, so the two overlap at age 16, our arithmetic on the published age ranges. An adult reader who searched for the WISC-V version should know that the adult question is answered by the WAIS rows, and the Pearson WAIS-5 product page gives the publication year (2024), the age range and the qualification level (C).

One more detail in the table deserves a sentence. Arithmetic left the WMI between the WAIS-IV and the WAIS-5. In Pearson's WAIS-5 ancillary index flyer, read October 29, 2026, Arithmetic appears with Matrix Reasoning, Figure Weights and Set Relations in the expanded fluid index and with Figure Weights in the quantitative reasoning index. The sibling page on the quantitative reasoning index covers that score, and the practical point here is that a mental arithmetic task counted toward working memory on one edition and toward reasoning on the next.

3 Why is the same index name not the same measurement?

A WMI from one battery is a different composite from the WMI of another, so the label alone does not tell you what was measured and does not allow a score for score comparison. The three Pearson recipes differ in what the second subtest asks for and in how much of the index is auditory.

The WAIS-IV pairs Digit Span with Arithmetic, a task of solving problems mentally. Its WMI therefore mixes a repetition task with a numerical one. The WAIS-5 drops Arithmetic from the index and uses Digit Sequencing and Running Digits. Pearson's comparison flyer describes Running Digits as a new subtest that measures auditory working memory and requires flexibility in processing information and a progressive shift of attention, and Pearson's ancillary flyer files both subtests under its auditory working memory indexes. The WISC-V keeps Digit Span, which is auditory, and adds Picture Span, which Pearson's product page calls a new visual working memory subtest. So of the three, the WISC-V is the only primary WMI that mixes auditory and visual material, and both WAIS-5 primary subtests belong to Pearson's auditory group. The ancillary scores exist to fill that gap, a point the next section develops.

Pearson itself treats the WAIS-5 change as a design decision. Its ancillary index flyer says that adding visual working memory enhances the scale's clinical utility because of the domain-specific clinical sensitivity of working memory abilities. That is the publisher's rationale, offered for its own batteries.

An independent check exists on the whole structure. Canivez, Watkins, McGill and Dombrowski analyzed the WAIS-5 standardization data (N = 2,020) in a 2026 paper in Assessment. They report that their analyses did not support five latent factors with separate Visual Spatial and Fluid Reasoning factors, supported a four factor model dominated by a general intelligence factor, and concluded that interpretation should rest primarily, if not exclusively, on the Full Scale IQ as an estimate of psychometric g. The abstract does not single out the working memory factor, so this page does not claim the study says anything about the WMI in particular. The reasonable reading is cautious: an index is a report of a subtest pair, whether that pair behaves as a separate factor is a question for evidence, and the owner of a score should hold index-level interpretations more loosely than the Full Scale IQ.

For a reader, three consequences follow. First, never compare a WAIS-IV WMI with a WAIS-5 WMI as if the subtest pair were the same, and the other changes between the editions are a separate topic. Second, when a report says "WMI," find the subtests behind it before reading the number. Third, a WMI from an online battery should be read against that battery's own recipe, and the section on the ACIS index below states it.

4 What are the auditory and visual working memory indexes?

The auditory and visual working memory indexes (AWMI and VWMI) split working memory by the sense through which the material arrives, and they are ancillary scores read beside the WMI, not replacements for it. Pearson builds them differently by battery, which is one more reason to read the recipe.

On the WISC-V, Pearson's sample interpretive report says the Auditory Working Memory Index is derived from the sum of scaled scores for the Digit Span and Letter-Number Sequencing subtests, with spoken numbers and letters recalled or sequenced aloud, and that the index measures the ability to register, maintain and manipulate verbally presented information. Pearson's WISC-V Integrated brochure describes a Visual Working Memory Index from the Picture Span and Spatial Span subtests and recommends contrasting it with the WMI and the AWMI to assess domain-specific working memory.

On the WAIS-5, the ancillary flyer lists four working memory indexes beyond the primary one. The Expanded Working Memory index draws on six subtests: Digit Sequencing, Running Digits, Digits Backward, Symbol Span, Spatial Addition and Letter-Number Sequencing. The Visual Working Memory index uses Symbol Span and Spatial Addition. The auditory side is divided into two indexes: Auditory Working Memory-Registration uses Digits Forward and Running Digits, and Auditory Working Memory-Manipulation uses Digit Sequencing, Digits Backward and Letter-Number Sequencing. That second split is a different distinction from auditory versus visual. It separates simply taking in and holding a sequence from reordering it, and it is the same idea the ACIS manual uses when it reads Digit Span beside Alphanumeric Sequencing.

Is the split real in adults? Two experimental papers in the Journal of Experimental Psychology: General speak to it, and they pull in different directions. Shah and Miyake (1996), in the Journal of Experimental Psychology: General, tested college students and found that a spatial span task correlated with spatial ability measures but not verbal ability measures, while a reading span task correlated with verbal ability measures but not spatial ones, which they present as evidence of separable spatial and verbal working memory resources. Kane and colleagues (2004) tested 236 participants on verbal and visuospatial span tasks and found that the working memory tasks largely reflected a domain-general factor, whereas short-term memory tasks based on the same stimuli were much more domain specific. Taken together, the studies support a reading that holds for a score: a gap between an auditory and a visual index can reflect real differences in how material is stored and rehearsed, and a large share of the underlying ability is shared across the two.

The ACIS composites follow the same logic with a smaller menu. The technical manual, read October 29, 2026, lists AWMI and VWMI among its composites. It says AWMI "focuses on auditory working memory through Digit Span and Alphanumeric Sequencing" and that VWMI "focuses on visual working memory through Visual Sequence and therefore requires careful single indicator caution." The page on the auditory memory test covers the spoken span formats, the page on the visual memory test covers the visual ones, and the sibling page on the Letter Number Sequencing test covers the task Pearson uses for the auditory manipulation side.

5 How can an adult get a normed Working Memory Index?

An adult can get a normed WMI from a psychologist who gives a Wechsler battery or from a normed online battery, and the routes differ in supervision, in the recipe behind the index and in what the report shows. The table sets them side by side. ACIS prices and times, and the Pearson kit price, were read on October 29, 2026 and can change. Cells marked "not stated" mean the source read gave no figure.

The clinician route is the reference. Pearson's WAIS-5 product page lists the 1,784 dollar print kit and the administration times above, and a clinician sets the fee for an evaluation. The times in the table are for the whole test, not for the working memory subtests alone, and Pearson's page gives no WMI specific time. The clinical route also brings what an online page cannot: an examiner who watches the session, notes distraction and can stop to check hearing or vision. If the question is a diagnostic or a school or workplace accommodation question, that route is the right one, and the section on uses below says why.

Free memory games are a different product. They can be enjoyable and may show whether you improve on one task, but a score becomes a standard score only when it is compared with a reference group of the same age, and whether a free tool does that is something to check on its own page. The page on free IQ tests explains what a free result can and cannot support, and practice tests built for job screening train a test format, which is not the same thing as measuring an index.

ACIS is a seller in this market, so treat the last four rows as a disclosure. Other normed online batteries exist, and the page on the best online IQ tests and the page on where to take an IQ test compare them across the whole range of abilities rather than for working memory alone. A reader who wants a broad screen of several abilities in one sitting can start from the page on the cognitive ability test, and one who wants a general adult test with a profile can read the page on IQ testing for adults.

6 What does the ACIS Working Memory Index consist of?

The ACIS Working Memory Index is built from three subtests, Digit Span, Alphanumeric Sequencing and Visual Sequence, and a form that holds only the first two reports a partial index. The three subtests are scaled scores from 1 to 19 (mean 10, standard deviation 3), and the index sits on the scale with mean 100 and standard deviation 15, with a percentile and a 95 percent confidence interval. The report describes the index in these words: "Auditory and visual working memory under attentional control, covering storage, manipulation, modality, and sequence demands." Each subtest has its own page, and the pages describe the construct without disclosing items.

The Digit Span page frames the task as immediate auditory-verbal storage and, in harder versions, active manipulation of ordered material, with attention, sequencing and resistance to interference all involved. The Alphanumeric Sequencing page calls it working memory under active reorganization, more demanding than simple recall because storage and mental control are needed at once. The Visual Sequence page frames it as temporary storage for ordered visual or spatial information without relying entirely on verbal rehearsal. The manual, read October 29, 2026, places Visual Sequence in the WMI and states that it "belongs to WMI, not to VSI as a primary score," which matters for a reader who expects a visual task to land in the spatial index.

The manual offers three reading rules for the pattern across the subtests. If Digit Span is adequate and Alphanumeric Sequencing is weaker, the person may maintain information but have difficulty reorganizing it under rules. A high Visual Sequence score with a lower Digit Span "may suggest" stronger visual than auditory working memory. A low Visual Sequence score beside adequate visual spatial reasoning may suggest that the weakness lies in visual sequence maintenance and not in visual processing itself. These describe profile shapes, they are not diagnoses, and each depends on every score carrying its own uncertainty.

Which form holds which subtest decides what the report can show. The manual's availability matrix lists the WMI as "Partial" for Quick and for Optimized, which each hold Digit Span and Alphanumeric Sequencing, and complete for the Full Scale form, which holds all three. The matrix lists AWMI, VWMI and the cognitive proficiency composite (CPI) among the Full Scale composites, and the manual describes CPI as combining working memory and processing speed. The Custom Test, at 5 dollars per subtest, lets a buyer pick the three, and its description states that "any domain you complete returns its full index score, and every subtest returns its scaled score." Three subtests at 5 dollars each is 15 dollars, our arithmetic on the posted price, and the Full Scale form costs the same as ten Custom subtests.

The free trial, no card, started from the Full Scale form opens five subtests, among them Digit Span, Alphanumeric Sequencing and Visual Sequence, and finished trial subtests are kept if the person later unlocks a form that includes them. This page does not claim that the trial returns an index. The example reports are the place to see how an index is displayed before paying, and the technical manual holds the documentation for readers who want it.

7 How is a Working Memory Index reported and read?

A WMI is reported as a standard score with a percentile rank and a confidence interval, and the interval is the part that tells you how much weight one number can carry. The route from tasks to the score has four steps. Each subtest raw score converts to a scaled score against the age reference group, the scaled scores of the subtests in the index are summed, the sum converts to the index score, and the report adds the percentile rank and the 95 percent confidence interval. Pearson's WAIS-5 and WAIS-IV sample reports show those columns for every index, and the page on how IQ scores are normed explains the reference group step in general terms.

The scale gives the score its meaning. With a mean of 100 and a standard deviation of 15, an index of 85 sits one standard deviation below the mean, which is about the 16th percentile on the normal curve, and an index of 115 sits about one standard deviation above, near the 84th percentile (our arithmetic from the normal curve, not a figure from any report). Percentile and standard score are two views of the same standing, and the page on IQ score versus percentile explains why they cannot be averaged. The IQ percentile calculator converts one to the other, and the IQ rarity calculator on this site turns it into a one in X figure.

Precision is the other half. A score is an estimate with error, and the 95 percent confidence interval is the range within which the person's standing on that task set probably lies. Standard 2.3 of the Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014) says that for each total score, subscore or combination of scores that is to be interpreted, estimates of relevant indices of reliability and precision should be reported, and its comment says it is not enough to report them for total scores when subscores are interpreted, because total scores can be acceptably consistent while subscores have unacceptably low reliability. That is why this page treats the WMI, a combination of scores, as something to read with its interval, and the single subtest or the single indicator composite as something to read with more caution. The page on reliability and validity gives the vocabulary.

Last, the reference group fixes the meaning. A WMI of 100 means average for the reference group of that battery and that age, so a 100 on the WAIS-5 and a 100 on an online battery are each average against their own group and are not the same measurement. This is the reason the section above insists on knowing the recipe. It is also why an age band matters: the ACIS adult norms cover ages 16 to 90, and working memory performance is read against the person's age, not against all adults at once.

8 How should a Working Memory Index far below or above the other indices be read?

A WMI that sits far from the other indices is a prompt to look at the subtests, the interval and the testing conditions, and by itself it cannot say why the gap exists. Pearson's score reports treat a gap as a statistical question first. The WAIS-IV sample score report has a section called Index Level Discrepancy Comparisons that lists, for each pair of indices, the two scores, the difference, a critical value at the .05 level, whether the difference is significant and a base rate. It has a similar section for pairs of subtests inside an index, including Digit Span against Arithmetic. Two separate questions sit behind those columns: whether the difference is larger than measurement error, and how often a difference of that size occurs in the reference sample. The page on index score differences works through both with a published example and shows how large a gap must be before it means something, which is why this page does not repeat the thresholds.

Look inside the index before looking across. A WMI is an average of its subtests, and two subtests that tell different stories produce a middle number that describes neither. On the WAIS-IV that means comparing Digit Span with Arithmetic. In ACIS it means comparing Digit Span, Alphanumeric Sequencing and Visual Sequence, using the manual's reading rules given above, and remembering that the VWMI rests on one task. A low index built from one weak subtest and two ordinary ones is a different finding from a low index built from three weak ones.

Then look at the neighbouring composites. Pearson's WAIS-IV score report describes the General Ability Index as an optional composite summary score that is less sensitive to the influence of working memory and processing speed, and adds that because working memory and processing speed are vital to a comprehensive evaluation, the GAI does not have the breadth of construct coverage of the Full Scale IQ. The page on the General Ability Index explains when a Full Scale IQ and a GAI diverge and which one answers which question. The cognitive proficiency composite goes the other way. The ACIS manual describes it as combining working memory and processing speed, and Pearson's WAIS-5 ancillary flyer lists Digit Sequencing, Running Digits, Coding and Symbol Search under its Cognitive Proficiency index. The sibling page on the Cognitive Proficiency Index takes that composite apart.

What can a low WMI mean? Several things, and the score cannot choose among them. Pearson's WISC-V report says the WMI requires attention and concentration along with visual and auditory discrimination, so a low value can reflect how well the person could attend and hear on the day. The Digit Span page lists distraction, anxiety, sequencing difficulty and limits in active manipulation as possible reasons for a weaker result, and the Alphanumeric Sequencing page adds that a weaker result can appear even when simple span is adequate, because sorting and reordering add executive demand. Fatigue, noise and a poor audio setup belong on the same list. A genuine and stable difference in working memory is one possibility among these, and a single session cannot separate it from the others.

What can it not mean? It cannot diagnose or rule out any condition. Group findings are the wrong tool for reading one person's score: in a study of 116 adults with ADHD and 116 matched controls on the WAIS-IV, Theiling and Petermann (2016) reported group-level decrements on subtests with working memory and processing speed demands in the Journal of Attention Disorders, and the page on IQ tests for adults with ADHD covers what a group result does and does not say about a person holding one score.

A WMI above the other indices deserves the same discipline, in the other direction. It is a pattern in the profile, not a problem to solve, and the same checks apply: the subtests behind it, the interval, and the conditions.

9 What does research say about working memory and reasoning?

Working memory capacity is among the abilities most closely tied to fluid reasoning in the research literature, which is why a WMI belongs in an IQ battery, but the link holds most strongly for tasks that load on attention control and less for simple storage. Three papers anchor that statement.

Engle, Tuholski, Laughlin and Conway (1999), in the Journal of Experimental Psychology: General, had 133 participants perform 11 memory tasks, 2 tests of general fluid intelligence and the verbal and quantitative Scholastic Aptitude Tests. Their structural equation modeling suggested that short-term and working memory are separate but highly related constructs, and they report that working memory shows a strong connection to fluid intelligence while short-term memory does not. They argue that working memory capacity and fluid intelligence reflect the ability to keep a representation active, particularly in the face of interference and distraction.

Kane and colleagues (2004), in the same journal, tested 236 participants and found that the working memory span tasks largely reflected a domain-general factor, a construct that was a strong predictor of fluid intelligence and a weaker predictor of domain-specific reasoning, while the short-term memory tasks, built on the same stimuli, were much more domain specific and showed the reverse pattern. Unsworth and Engle (2007), in the Psychological Bulletin, reviewed the comparison of simple and complex span tasks and concluded that the two largely measure the same basic subcomponent processes, such as rehearsal, maintenance, updating and controlled search, but differ in how much each process operates in a given task.

Three cautions keep this evidence in proportion. These are group-level correlations from tasks and samples that differ from any commercial index, so they say that working memory and reasoning tend to rise together across people and cannot say that a given person's WMI predicts that person's reasoning. They do not say which of the two causes the other, and the designs behind them do not allow that claim. And they concern constructs, while an index is a particular recipe. A task that only repeats a sequence taxes storage, and a task that reverses or re-orders it adds the manipulation that the ACIS manual describes as sitting on top of storage. The page on the short term memory test covers the storage side of that line, and the page on how IQ relates to memory places working memory among the other memory systems.

10 What conditions help an unsupervised Working Memory Index give a fair score?

An unsupervised WMI is only as fair as the session behind it, because two of the three ACIS subtests are delivered as audio and all three are sensitive to interruption. Digit Span and Alphanumeric Sequencing present their items as audio and need working sound, so check the sound before you start and take the session where you can hear every item. Pearson describes the WMI as requiring auditory discrimination, which means that a score from a session where the digits were hard to hear partly measures the listening conditions. Visual Sequence is on screen and needs a click response, so use a screen and a pointing device you can control accurately.

Choose a quiet room and a time when you are alert. Breaks are allowed between subtests, progress is saved between subtests and a buyer has 30 days to finish, so there is no reason to take a working memory subtest after hours of other tests or in the middle of a busy afternoon. Do not write the digits down, record them or use any other aid, because copying turns a working memory task into a copying task and the score would no longer describe your working memory. Alphanumeric Sequencing asks for letters in alphabetical order, so it assumes the English alphabet, and the test as a whole is in English only.

The Standards for Educational and Psychological Testing speak to the principle. Standard 6.1 says test administrators should follow carefully the standardized procedures for administration and scoring specified by the test developer, and Standard 6.3 says changes or disruptions to standardized administration should be documented and reported to the test user. An unsupervised session has no administrator to record a disruption, so the test taker is the only record. If the doorbell rang during a subtest, if the audio dropped, or if you were interrupted, treat that subtest score as less trustworthy than the others, and do not build a conclusion on it.

11 What can a Working Memory Index be used for, and what can it not?

A WMI can organize a conversation about a profile, and it cannot diagnose a condition, certify an accommodation or stand in for a clinical evaluation. What it can do is specific. It can show where working memory stands against an age reference group, how that compares with the other indices in the same report, and whether a Full Scale IQ and a General Ability Index differ because of working memory and processing speed. It can help a person decide what to ask a professional, and it can satisfy curiosity about a pattern the person has noticed in everyday tasks.

What it cannot do is also specific. An online, unsupervised index is not a clinical instrument, and it is not for hiring, school accommodations or admission to high IQ societies. Pearson's ancillary index flyer, read October 29, 2026, names learning disability determination in some U.S. states and admission to programs or organizations for intellectually gifted individuals as examples of applications that can require an expanded index score, and those uses rest on a supervised battery given by a qualified professional. A reader whose question is about giftedness can start from the page on a gifted test for adults, which explains what each route can and cannot confirm.

Nor does a WMI measure change. A single score is a standing at one time on one set of tasks, and a claim that a program or habit has raised working memory needs a design that compares groups, which a single report cannot supply.

12 Where ACIS sits, and what a buyer should do

ACIS offers a three subtest Working Memory Index with adult norms for ages 16 to 90 from 15 dollars, and it is an online, unsupervised, non clinical, English only instrument whose score should be read with those limits in view. ACIS sells these tests, so this section is a disclosure and the table above should be checked against it. Prices were read on October 29, 2026 and can change.

The strengths are specific. The index is built from three subtests that cover spoken span, spoken reordering and visual order, rather than from a single digit task. The Full Scale form adds the AWMI and VWMI composites so an auditory and visual gap can be looked at. The report gives the index with a percentile and a 95 percent confidence interval, the payment is one time with no subscription, progress is saved, and a buyer has 30 days to finish. The guarantee reads: "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.

The limits matter as much. The test is online and unsupervised, so conditions are not verified and nobody observes the session. It is English only. It is not a clinical or diagnostic instrument, and it is not for hiring, school accommodations or admission to high IQ societies. Quick and Optimized return a partial WMI from two auditory subtests, VWMI rests on one subtest, and only the Full Scale form returns the complete WMI together with the Full Scale IQ and the other composites. A WMI from ACIS is not interchangeable with a WMI from a Wechsler battery, and this page does not suggest that it is.

The Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014) bear on exactly these limits. Standard 1.14 says that when interpretation of subscores, score differences or profiles is suggested, the rationale and relevant evidence in support of the interpretation should be provided, and its comment says that when a test provides more than one score, the distinctiveness and reliability of the separate scores should be demonstrated. Standard 2.3, cited above, asks for estimates of reliability and precision for each score that is to be interpreted. This page applies that reading: the recipe behind the index is stated, the single indicator caution is stated, the limits are stated, and the technical manual is the place for the documentation. The American Psychological Association is one of the three organizations that publish the Standards.

What to do next depends on the question. If the question is only about working memory, the Custom Test with the three subtests at 15 dollars returns the full index. If the question is how working memory compares with reasoning, knowledge, space and speed, the Full Scale form at 50 dollars returns all six indices, the Full Scale IQ with its interval and the working memory composites. Look at an example report before paying, try the free trial, which needs no card, to see how the three working memory subtests feel, and keep one rule in mind whatever you choose: if the question is clinical, bring it to a psychologist.

13 Sources Behind This Page

All web pages and documents were opened on October 29, 2026. Pearson documents are cited as published by the vendor, and the pages are the vendor's own description of its products. The sample reports use fictional examinees, and only their structure is described here.

1. AERA, APA and NCME. (2014). Standards for Educational and Psychological Testing. American Educational Research Association. Open access edition, standards 1.14, 2.3, 6.1 and 6.3. testingstandards.net
2. Canivez, G., Watkins, M., McGill, R., and Dombrowski, S. (2026). Construct validity of the WAIS-5: Complementary exploratory and confirmatory factor analyses of the 20 primary and secondary subtests. Assessment. doi.org/10.1177/10731911251412219
3. Engle, R., Tuholski, S., Laughlin, J., and Conway, A. (1999). Working memory, short-term memory, and general fluid intelligence: A latent-variable approach. Journal of Experimental Psychology: General, 128(3), 309 to 331. doi.org/10.1037/0096-3445.128.3.309
4. Kane, M., Hambrick, D., Tuholski, S., Wilhelm, O., Payne, T., and Engle, R. (2004). The generality of working memory capacity: A latent-variable approach to verbal and visuospatial memory span and reasoning. Journal of Experimental Psychology: General, 133(2), 189 to 217. doi.org/10.1037/0096-3445.133.2.189
5. Shah, P., and Miyake, A. (1996). The separability of working memory resources for spatial thinking and language processing: An individual differences approach. Journal of Experimental Psychology: General, 125(1), 4 to 27. doi.org/10.1037/0096-3445.125.1.4
6. 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. doi.org/10.1177/1087054713518241
7. Unsworth, N., and Engle, R. (2007). On the division of short-term and working memory: An examination of simple and complex span and their relation to higher order abilities. Psychological Bulletin, 133(6), 1038 to 1066. doi.org/10.1037/0033-2909.133.6.1038
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9. Pearson. (2025). WAIS-5 overview brochure: structure of the full scale, primary index scales and ancillary index scales. pearsonassessments.com
10. Pearson. (2024). WAIS-IV and WAIS-5 comparison flyer: core, supplemental, primary and secondary subtests, and the new subtests. pearsonassessments.com
11. Pearson. (2024). WAIS-5 ancillary index scores flyer: the subtests behind each expanded, domain-specific and summary index. pearsonassessments.com
12. Pearson. (2024). WAIS-5 sample score report: composite score summary, subtest scaled score profile. pearsonassessments.com
13. Pearson. (2016). WAIS-IV sample score report: working memory subtests summary, index level discrepancy comparisons, General Ability Index note. pearsonassessments.com
14. Pearson. Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V), product page: Working Memory Index subtests, ancillary index scores, age range, publication year. pearsonassessments.com
15. Pearson. (2020). WISC-V interpretive report, sample: description of the Working Memory Index and the Auditory Working Memory Index, standard score metric. pearsonassessments.com
16. Pearson. WISC-V Integrated brochure: Visual Working Memory Index from Picture Span and Spatial Span. pearsonclinical.asia

14 Frequently Asked Questions