Assessment of Processing Speed
A curriculum-based screening tool for learners aged 6–18+. Ten short activities, age-adjusted content, and a clear composite score that tells you where to focus next.
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The Assessment of Processing Speed (APS) is a curriculum-based screening tool designed for learners aged 6–18+. It helps teachers identify children and young people who may have slower processing speed — a cognitive factor that affects how quickly a person can take in, understand, and respond to information.
The APS comprises 10 activities with 10 items each (100 points maximum), administered across six developmental age groups (6–8, 9–10, 11–12, 13–14, 15–16, 16–18+). Each age group receives a content-adjusted version calibrated to the cognitive demands appropriate for that developmental stage.
Unlike standardised IQ-based assessments, this tool focuses on observable classroom-relevant tasks — matching, counting, pattern recognition, letter and number discrimination, and arithmetic — giving teachers practical, actionable insights rather than abstract scores.
Critical difference from traditional processing-speed tests: The APS uses age-adjusted content across six versions. Younger children receive developmentally simpler items (single-digit arithmetic, CVC words, 4-element patterns), while older adolescents receive more complex items (multi-digit multiplication and division, technical vocabulary, 10-element patterns).
This means the test measures processing speed within the child's zone of proximal development, rather than conflating content difficulty with processing speed. Because content difficulty is matched to each age group, expected completion times across groups are more compressed than they would be if all ages took the same test.
Processing speed increases exponentially during childhood and adolescence, reaching near-adult levels around age 15–16. Kail's seminal meta-analysis of 72 studies (1,826 response-time pairs) established that children's response times are a linear function of adult response times, with the slowing coefficient declining exponentially with age.
Approximate processing speed ratios by age (relative to adult = 1.0)
Source: Kail (1991, 1993), Kail & Park (1992), Miller & Vernon (1997), Kail & Ferrer (2007).
Working memory capacity increases steadily through childhood and adolescence. Cowan (2016) documented that visual WM performance improves from approximately 1.5–2 items at age 5–6 to 3–4 items in adults. This directly informs Activities 7 and 8, which scale pattern length from 4 elements (ages 6–8) to 10 elements (ages 16–18+).
Automaticity for single-digit facts corresponds to a response time of approximately 2–3 seconds per problem. These benchmarks inform the time expectations for Activities 9 and 10, which progressively incorporate all four operations:
- Ages 6–10: Addition (Act. 9) and Subtraction (Act. 10) only
- Ages 11–12: Multiplication introduced in Act. 9 (basic table facts, e.g. 6×7, 12×8)
- Ages 13–14: Multiplication scales to 1d×2d (e.g. 12×7); Division introduced in Act. 10 (table facts)
- Ages 15–16: Multiplication includes 1d×2d and 12×12; Division uses table-derived facts
- Ages 16–18+: Manageable 2d×2d multiplication (e.g. 13×14); Division stays table-derived
Research on rapid automatised naming (RAN) shows naming speed improves from approximately 1.5–2.0 seconds per item at age 6 to under 0.8 seconds by age 14–15 (Denckla & Rudel, 1976; Wolf & Bowers, 1999). Activity 6 (word recognition) is calibrated accordingly.
Time and accuracy benchmarks are cross-referenced against established instruments:
- WISC-V Processing Speed Index — Standard score metric (M=100, SD=15) for ages 6–16:11.
- NIH Toolbox Pattern Comparison — Normative data for ages 5–85 (N=4,859).
- Kail & Ferrer (2007) — N=503 longitudinal models confirming exponential growth in processing speed.
- TVPS-4 (Martin, 2017) — Normative data on visual discrimination speed.
Each student receives a Composite Performance Score derived from two weighted components:
Number of correct answers across all 10 activities (out of 100). Primary measure of correct processing.
Total time compared to age-adjusted benchmarks. Measures processing efficiency.
Time score scale
The 60/40 accuracy-to-time ratio reflects current psychometric practice. Separating these components helps a teacher tell apart students who are accurate but slow (potential processing speed deficit) versus fast but inaccurate (potential attention or impulsivity issue). The 60% accuracy weight ensures correctness remains the primary determinant.
A 10-year-old scores 78/100 in 52 minutes. Expected time for age 9–10 = 50 min. Actual time is 4% over expected → 30 time points. CPS = (78 ÷ 100 × 60) + 30 = 46.8 + 30 = 76.8 → Tier 4 Proficient.
A clear performance band, not a label
Once the CPS (0–100) is calculated, students are assigned to one of five performance tiers, using standard-deviation boundaries analogous to WISC-V qualitative descriptors.
Significantly below age expectations in accuracy and/or speed. Prompt support and, where a teacher is concerned, a referral for professional assessment are suggested. Approximately >1.5 SD below mean on standardised processing speed measures.
Below age expectations. Emerging skills that need targeted intervention and additional practice to consolidate. Approximately 1.0–1.5 SD below mean.
Meets age-appropriate expectations. The student processes information at an adequate rate and demonstrates sufficient accuracy for their developmental stage. Average range (±0.5 SD).
Above age expectations. Strong processing speed and high accuracy, reflecting well-developed visual discrimination and cognitive efficiency. Approximately 0.5–1.5 SD above mean.
Well above age expectations. Exceptional processing speed, near-perfect accuracy, and efficient cognitive functioning relative to peers. Approximately >1.5 SD above mean.
Calibrated to developmental norms
Benchmarks for a student performing at the Competent level (Tier 3), calibrated using Kail's (1991, 2007) processing speed growth curves.
| Age group | Expected time | Fast / Advanced |
|---|---|---|
| 6–8 | 55–75 min | < 40 min |
| 9–10 | 42–55 min | < 30 min |
| 11–12 | 35–48 min | < 25 min |
| 13–14 | 32–44 min | < 22 min |
| 15–16 | 30–42 min | < 20 min |
| 16–18+ | 30–42 min | < 20 min |
Note: The convergence of expected times for ages 15–16 and 16–18+ reflects that processing speed reaches near-adult ceiling by age 15, while content difficulty continues to increase.
The assessment consists of 10 activities, each containing 10 questions, for a total of 100 items. Each correct answer scores 1 point. Time taken per activity is also recorded.
Activities progress from concrete visual tasks to more abstract academic skills, following the natural developmental sequence:
From visual discrimination to arithmetic
Children match a target image to one of four picture options, assessing perceptual matching, attention to detail, and figure-ground discrimination.
What a low score may point to: Difficulty distinguishing similar visual forms; a possible visual perceptual weakness. A professional may consider a TVPS-4.
Abstract shapes and silhouettes, testing form constancy, shape recognition, and geometric abstraction without semantic cues.
What a low score may point to: Trouble with geometric forms; check visual-spatial processing. A reason to look further at visual-spatial skills.
Children count groups of objects displayed on screen, assessing visual scanning, enumeration, sustained attention, and working memory.
What a low score may point to: Slow or inaccurate counting; may reflect attention or working memory demands. Only a professional can assess attention disorders.
Identify which letter is different from a group, testing letter recognition, reversal awareness (b/d/p/q), and the phonological link.
What a low score may point to: Confusion of reversals (b/d/p/q); common at ages 6–8. Persistent errors beyond age 8 are a reason to seek a reading assessment.
Similar to letter discrimination but with numerals, assessing numeral recognition, visual-numeric processing, and digit discrimination.
What a low score may point to: Digit confusion; a reason to look further at number skills. Check whether errors are reversal-based (e.g., 56/65) or random.
Children identify a matching word from options, testing sight-word fluency, lexical access speed, and orthographic processing.
What a low score may point to: Slow word recognition; possible reading fluency or phonological processing weakness. Investigate RAN deficits.
A repeating letter pattern is shown with a missing element — the child selects what comes next, testing sequential working memory, verbal encoding, and pattern recall.
What a low score may point to: Difficulty with letter sequences; reflects working memory or executive function concerns. Compare to Act. 8 for domain specificity.
Same as Activity 7 but with number sequences, assessing sequential working memory, numeric encoding, and numerical pattern recognition.
What a low score may point to: Difficulty with number sequences; if Act. 7 is intact but Act. 8 is weak, consider numerical processing-specific support.
Mental arithmetic, calibrated by age. Ages 6–10 focus on addition only. From age 11+ multiplication is introduced and scales from basic times tables to manageable 2d×2d in rapid-recall range.
What a low score may point to: Slow or inaccurate addition/multiplication; may reflect developing maths fluency or continued reliance on counting. Compare addition vs multiplication items to distinguish fact retrieval from procedural difficulty.
Subtraction across all ages; division introduced from age 13–14, using table-derived facts up to 12×12. With Activity 9 this gives a complete picture of arithmetic automaticity.
What a low score may point to: Slow or inaccurate subtraction/division; a stronger reason to look at number processing when combined with Act. 9 weakness. Division errors specifically may indicate weak times-table fluency.
Beyond the total CPS, reviewing performance on individual activities can pinpoint specific processing weaknesses:
Global Processing Speed Deficit
Low scores across Activities 1–6 (all speed-dependent tasks) with relatively better performance on Activities 7–10. Suggests a pure processing speed weakness rather than a domain-specific difficulty.
Working Memory Deficit
Low scores on Activities 7–8 (pattern completion) with adequate performance on 1–6. Pattern completion requires holding multiple elements in mind — weakness here points to working memory as the limiting factor.
Math Processing Deficit
Low scores on Activities 9–10 with adequate performance elsewhere. Suggests domain-specific difficulty with arithmetic fluency. From age 11+, compare addition items (1–5) vs multiplication/division items (6–10) to differentiate fact retrieval from procedural calculation difficulty.
Reading / Language Processing Deficit
Low scores on Activity 4 (letter discrimination) and Activity 6 (word recognition) with adequate visual discrimination on Activities 1–3. This profile is often seen in children who go on to be assessed for reading difficulties; it is a reason to look further, not a finding.
Attention Deficit Pattern
Inconsistent performance across activities (high accuracy on some, very low on others) combined with significantly slow completion. A 'saw-tooth' profile, especially with errors increasing on later activities, may reflect fatigue or difficulty sustaining attention during the session. Only a qualified professional can assess attention disorders.
After each test, a detailed results page shows:
- Overall CPS out of 100 with a 5-tier performance classification
- Activity-by-activity scores with bar and radar charts
- Time analysis per activity — highlighting where a child is taking significantly longer
- Strengths and areas for development automatically identified
- Pattern flags that group low scores by skill area (reading, number, working memory, attention) as prompts for follow-up, not a diagnosis
When a child has taken the test more than once, the Compare Results feature shows improvement or regression across attempts, helping track progress over time.
Longitudinal tracking. When re-testing a student who has moved to a new age group, meaningful comparison should focus on Tier placement and CPS (which is already age-normalised) rather than raw accuracy scores. A student who maintains the same Tier across successive age groups is developing on track.
Built for the people doing the work
A quick, structured way to screen for processing speed concerns.
Concrete data to support referral and intervention decisions.
Work alongside educators to understand a child's learning profile.
The APS is a screening instrument that can inform whether further professional assessment may be beneficial. It is not a diagnostic tool and should not be used for placement, eligibility, or retention decisions on its own.
- Carlozzi et al. (2015). The NIH Toolbox Pattern Comparison Processing Speed Test: Normative data. Archives of Clinical Neuropsychology, 30(5), 359–368.
- Cowan, N. (2016). Working memory maturation. Perspectives on Psychological Science, 11(2), 239–264.
- Denckla & Rudel (1976). Rapid 'automatized' naming (R.A.N.). Neuropsychologia, 14(4), 471–479.
- Gathercole et al. (2004). The structure of working memory from 4 to 15 years of age. Developmental Psychology, 40(2), 177–190.
- Hale, S. (1990). A global developmental trend in cognitive processing speed. Child Development, 61(3), 653–663.
- Kail, R. (1991). Developmental change in speed of processing during childhood and adolescence. Psychological Bulletin, 109(3), 490–501.
- Kail & Ferrer (2007). Processing speed in childhood and adolescence: Longitudinal models. Child Development, 78(6), 1760–1770.
- Martin, N. (2017). Test of Visual Perception Skills – Fourth Edition (TVPS-4).
- Van de Walle & Lovin (2006). Teaching student-centered mathematics: Grades 3–5.
- Wechsler, D. (2014). Wechsler Intelligence Scale for Children – Fifth Edition (WISC-V).
- Wolf & Bowers (1999). The double-deficit hypothesis for the developmental dyslexias. Journal of Educational Psychology, 91(3), 415–438.
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Opens a separate demo application on another host. It is not covered by this site's Privacy Policy; please do not enter a child's real name there.