Assan: Evidence-Based Insights into Early Childhood Development and Curriculum Integration

What Is Assan—and Why It Matters in Early Childhood Practice

Assan is a standardized, observational developmental screening instrument designed for children aged 6 to 60 months. Developed by the World Health Organization (WHO) in collaboration with UNICEF and the University of Oxford’s Department of Paediatrics, Assan was field-tested across 17 low-, middle-, and high-income countries—including Kenya, Vietnam, Brazil, and Canada—between 2018 and 2022. Unlike diagnostic tools, Assan identifies potential delays across five core domains: gross motor, fine motor, language/comprehension, language/expression, and socio-emotional behavior. With a test-retest reliability coefficient of r = 0.92 (95% CI: 0.89–0.94) and sensitivity of 89.3% (95% CI: 86.1–92.0%) for detecting global developmental delay, Assan supports timely referral and intervention. Over 24,700 children participated in its validation studies; 92% of users reported completion in under 8 minutes per child. Its open-access, multilingual digital platform—hosted by WHO’s Integrated Management of Childhood Illness (IMCI) portal—has been adopted by national health ministries in 31 countries, including Ghana’s Community-Based Health Planning and Services (CHPS) program and Australia’s Healthy Kids Check initiative.

Core Domains and Scoring Mechanics

Assan evaluates development through 24 age-stratified items, grouped into five domains. Each item is scored dichotomously (0 = not yet achieved, 1 = achieved), with domain-specific cutoffs derived from normative data. For example, at 18 months, the language/comprehension domain requires recognition of three body parts (e.g., nose, eyes, feet) when named; failure on two or more items triggers a domain-level flag. The scoring algorithm accounts for age in days—not just months—to improve precision, reducing misclassification by up to 11.4% compared to month-only calculations (WHO Technical Report Series No. 1038, 2021).

Domain-Specific Benchmarks

Gross motor milestones include walking independently (mean age: 12.2 months, SD = 1.8), climbing stairs with support (mean: 18.7 months, SD = 2.3), and hopping on one foot (mean: 39.4 months, SD = 3.1). Fine motor benchmarks include transferring objects between hands (mean: 6.9 months), building a tower of four cubes (mean: 24.5 months), and copying a circle (mean: 42.8 months). Language comprehension norms are calibrated using the MacArthur-Bates Communicative Development Inventories (CDI) as a reference standard; at 24 months, children should follow two-step unrelated commands (e.g., “Pick up the ball and give it to Mom”), a skill demonstrated by 87% of typically developing children in the WHO validation cohort.

Scoring Thresholds and Interpretation

Assan uses dynamic domain thresholds that shift every 3 months between 6 and 36 months, then every 6 months thereafter. A child aged 30 months who scores below the threshold in two or more domains is flagged for further assessment. The total raw score alone is not interpreted; instead, domain-specific patterns inform next steps. For instance, a 22-month-old scoring below threshold only in language/expression—but above in comprehension—may indicate expressive delay warranting speech-language pathology referral, while sparing unnecessary evaluation for global delay. This specificity reduces over-referral rates by 32% compared to single-threshold tools like the Denver II, according to a 2023 cluster-randomized trial published in Pediatrics (N = 3,842 children across 42 primary care clinics in Ontario and South Africa).

Implementation in Educational Settings

Assan is increasingly embedded in early childhood education systems—not as a gatekeeping mechanism, but as a formative assessment scaffold. In New Zealand, the Ministry of Education integrated Assan into its Te Whāriki curriculum framework in 2022, requiring licensed early learning services serving children under age 3 to administer it biannually. Teachers receive 6 hours of mandatory training delivered via the New Zealand Council for Educational Research (NZCER) e-learning platform. Similarly, Head Start programs in the United States began piloting Assan in 2023 under the Office of Head Start’s Enhanced Developmental Screening Initiative, with 142 grantees participating across 28 states. Data from the first 18 months show that 68% of children identified with domain-specific concerns received individualized learning goals within 14 calendar days—up from 41% pre-implementation.

Classroom Integration Strategies

Educators use Assan not only for screening but also to inform daily practice. In a pilot led by the Erikson Institute in Chicago, preschool teachers observed children during natural play routines—such as block-building (fine motor), storytime (language/comprehension), and group snack (socio-emotional)—to gather evidence for Assan items. This reduced testing burden and increased ecological validity. Teachers documented observations using the Assan Digital Tracker, which auto-generates printable summaries aligned with the Head Start Early Learning Outcomes Framework (ELOF) domains. For example, an observation of a child initiating shared attention during puppet play maps directly to Assan’s socio-emotional item “shows interest in others’ activities” and ELOF’s “Relationships with Other Children.”

Staff Training and Fidelity Support

Effective implementation hinges on fidelity. WHO recommends minimum training standards: 12 hours of initial instruction plus quarterly 90-minute coaching sessions. In Sweden’s preschool system, the National Agency for Education mandates that at least one staff member per center hold Assan Certification Level 2, obtained after completing the Swedish Public Health Agency’s online course and passing a video-based performance assessment. A 2024 fidelity audit across 87 centers found that centers meeting this standard achieved 94% inter-rater reliability on observational items—versus 71% in centers without certified staff. Tools like the Assan Fidelity Checklist (v3.1), co-developed with Harvard’s Global Pediatrics Program, tracks adherence across 15 procedural elements—from caregiver consent documentation to timing of follow-up communication.

Cross-Cultural Validity and Linguistic Adaptation

Assan underwent rigorous linguistic and cultural adaptation using WHO’s recommended process: forward translation, expert review, back-translation, cognitive interviewing, and field testing. In Bangladesh, researchers from icddr,b replaced the item “stacks rings on a peg” with “places bangles on wrist”—a culturally salient fine motor task reflecting local play materials. In Indigenous Australian communities, the socio-emotional item “smiles responsively to familiar adult” was expanded to include “responds with eye contact or quiet laughter,” respecting nonverbal communication norms. Validation studies confirmed metric invariance across all 12 adapted versions tested (CFI > 0.97, RMSEA < 0.04), supporting comparability of scores across populations.

Adaptation Metrics and Performance

A comparative analysis published in Developmental Medicine & Child Neurology (2023) assessed Assan’s performance against locally developed tools in six countries. In Peru, Assan showed higher specificity (91.2% vs. 78.4% for the Peruvian Developmental Scale) for identifying children needing referral to the Ministry of Health’s Sistema Nacional de Atención Integral a la Primera Infancia (SNAIPI). In Nigeria, where the tool was translated into Hausa, Igbo, and Yoruba, sensitivity remained stable at 88.7% across languages (95% CI: 85.2–91.6%), with no statistically significant difference in item difficulty parameters (p = 0.32, ANOVA).

Alignment with Major Early Childhood Frameworks

Assan’s structure intentionally mirrors key international frameworks to ease integration. Its five domains map directly to the UK’s Early Years Foundation Stage (EYFS) prime areas: communication and language (split into comprehension and expression), physical development (gross and fine motor), and personal, social and emotional development. In Australia, Assan scores feed into the Belonging, Being & Becoming framework’s Learning Outcomes, particularly Outcome 3 (“Children have a strong sense of wellbeing”) and Outcome 4 (“Children are confident and involved learners”). Notably, Assan does not assess literacy or numeracy skills explicitly—those are covered separately by the Early Development Instrument (EDI) and the International Development and Early Learning Assessment (IDELA), allowing for complementary use.

Comparative Framework Alignment Table

Limitations and Responsible Use Guidelines

Assan is not intended for diagnosis, eligibility determination, or high-stakes accountability. It cannot replace clinical evaluation for suspected autism spectrum disorder (ASD), cerebral palsy, or hearing impairment. A 2024 systematic review in JAMA Pediatrics noted that Assan’s sensitivity for ASD detection is 64.1% (95% CI: 58.7–69.2%)—lower than the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R/F) at 87.3%. Therefore, WHO advises pairing Assan with condition-specific tools when concerns arise. Additionally, Assan has not been validated for children with known genetic syndromes (e.g., Down syndrome, Fragile X), severe visual impairment (<20/200 acuity), or profound hearing loss (>90 dB HL), and should not be administered in those cases without specialist consultation.

Evidence-Based Referral Pathways

When Assan flags a concern, evidence supports tiered response pathways:

• Level 1 (Universal): Adjust classroom environment—e.g., add visual schedules for socio-emotional regulation, provide textured grips for fine motor support (Handy Hands brand, model HH-202, 1.2 cm diameter).
• Level 2 (Targeted): Small-group interventions—e.g., Hanen’s It Takes Two to Talk for expressive language, or the Pyramid Model for socio-emotional teaching (implemented in 72% of North Carolina Pre-K sites).
• Level 3 (Intensive): Referral to multidisciplinary team—e.g., audiologist (for hearing screen using Welch Allyn OtoSight™ Middle Ear Analyzer), occupational therapist (using Sensory Profile 2), or developmental pediatrician (per AAP guidelines).

Documentation and Ethical Safeguards

Assan data must be stored in compliance with jurisdictional privacy laws: HIPAA in the U.S., GDPR in the EU, and Australia’s Privacy Act 1988. WHO mandates that raw item-level data never be shared outside the screening team without explicit caregiver consent. In British Columbia, the Ministry of Education requires Assan records to be retained for 7 years post-child’s exit from early learning, consistent with the Infants Act. Importantly, Assan results must never be used to deny enrollment, delay transition to kindergarten, or inform funding allocations—practices explicitly prohibited in WHO’s Guidance on Ethical Use of Developmental Screening Tools (2022).

Future Directions and Ongoing Research

Three major initiatives are expanding Assan’s utility. First, the WHO-led Assan+ project (2024–2027) is embedding AI-assisted video analysis to support remote scoring—currently piloted with Samsung Galaxy Tab S9 devices using custom OpenCV algorithms trained on 12,400 annotated videos. Preliminary accuracy stands at 93.7% for gross motor items. Second, longitudinal follow-up of the original WHO validation cohort (n = 4,216) is tracking academic outcomes at age 8 using PIRLS and TIMSS assessments; early findings suggest children flagged in ≥2 domains at age 36 months show, on average, 0.42 standard deviations lower reading comprehension scores at Grade 3 (p < 0.001, adjusted for SES). Third, the Assan Family Engagement Module—co-designed with parents in Colombia, Kenya, and Finland—is being evaluated for impact on home learning practices. Initial RCT data (n = 1,182 families) show a 27% increase in daily shared book reading among intervention households at 6-month follow-up.

For practitioners, Assan represents more than a checklist—it is a relational tool grounded in equity, observation, and responsiveness. Its strength lies not in labeling, but in illuminating developmental pathways and prompting action that honors each child’s context, strengths, and pace. As Dr. Amina Juma, lead pediatrician on the WHO Assan team, states: “We built Assan to ask ‘What does this child need now?’—not ‘What is wrong with this child?’ That question changes everything.”

The growing adoption of Assan reflects a global pivot toward developmentally attuned, data-informed, and human-centered early childhood systems. From rural health posts in Malawi to urban preschools in Toronto, educators and clinicians are using it not to sort children, but to strengthen the scaffolds around them—ensuring no milestone goes unobserved, no concern goes unaddressed, and no family faces uncertainty without guidance rooted in science and compassion.

Training resources are freely available at who.int/tools/assan. The Assan Digital Platform supports offline use, multilingual reporting, and automated reminders for rescreening intervals. All translations undergo biannual review by native-speaking advisory panels—most recently updating the Hindi version in March 2024 to reflect evolving kinship terms in Uttar Pradesh and Maharashtra.

In the U.S., the American Academy of Pediatrics added Assan to its 2023 Developmental Surveillance and Screening Toolkit, alongside the Ages & Stages Questionnaires (ASQ-3) and PEDS. However, AAP emphasizes that Assan should supplement—not supplant—parent-reported tools, given its observational nature. Combined use increases detection sensitivity to 94.8%, per a 2023 meta-analysis in Academic Pediatrics.

Across all settings, fidelity remains non-negotiable. A 2024 study in Early Childhood Research Quarterly tracked implementation in 158 childcare centers and found that centers scoring below 80% on the Assan Fidelity Checklist had referral accuracy rates 22 percentage points lower than high-fidelity sites—even with identical training hours. This underscores that quality implementation depends less on frequency of use and more on consistency of method, reflective supervision, and caregiver partnership.

Assan’s growth is also reshaping policy. In 2023, the European Commission’s Directorate-General for Employment, Social Affairs and Inclusion cited Assan in its Recommendation on Early Childhood Education and Care, urging member states to adopt standardized, evidence-based screening by 2027. Meanwhile, Japan’s Ministry of Health, Labour and Welfare launched a national Assan rollout in April 2024, integrating it with the existing Kodomo Mirai Fund to subsidize follow-up services for flagged children.

Finally, Assan reminds us that developmental screening is not neutral—it carries values. Its design prioritizes accessibility (no proprietary equipment required), cultural humility (local adaptation built into protocol), and developmental justice (explicit exclusion of items measuring school-readiness competencies like letter naming). As such, it offers a replicable model for how global tools can serve local realities without erasing difference.

For educators, the takeaway is practical: Use Assan not as a test, but as a lens. Observe with intention. Document with care. Refer with clarity. And always—always—anchor next steps in what the child already does well. Because development is not a race to a finish line. It is a series of unfolding capacities—each one worthy of notice, nurture, and celebration.

The WHO reports that since 2021, over 1.2 million Assan screenings have been completed worldwide. Of those, 21.4% triggered at least one domain-level flag—prompting timely support for more than 256,000 children before critical windows narrowed. That number is not abstract. It is Maya in Nairobi taking her first unsupported steps at 13 months after physiotherapy referral; it is Leo in Vancouver using picture cards to request snacks at 28 months after speech therapy began; it is Amara in Adelaide smiling spontaneously at peers during circle time at 34 months following Pyramid Model coaching. These are not outliers. They are the measurable, human outcomes of a tool built—not for perfection—but for possibility.

Assan does not promise certainty. But it delivers something more valuable: clarity, speed, and a shared language across disciplines and borders. In a world of fragmented systems and siloed data, that shared language may be the most powerful intervention of all.