# How does the WHO-GMM compare with the AbilityScore developmental assessment?

Canonical: https://pinnacleblooms.org/ask/how-does-the-who-gmm-compare-with-the-abilityscore-developmental-assessment
Publisher: Pinnacle Blooms Network / Bharath Healthcare Laboratories Private Limited

The WHO-GMM and the AbilityScore® do different jobs. The WHO-GMM is a population reference showing the broad, normal age window for six gross-motor milestones like sitting and walking. The AbilityScore® is a clinician-administered, whole-child assessment used at a Pinnacle centre to build your child's individual baseline and plan — they complement each other rather than compete.

*You may have spotted the WHO's gentle milestone charts and wondered how they sit alongside Pinnacle's own assessment — let's clear that up.*

## In short
The [WHO Windows of Achievement for Gross Motor Milestones](/who-gmm) and the AbilityScore® do two different jobs. The WHO-GMM is a research-based *population reference* — it tells you the broad age range in which healthy children worldwide tend to sit, stand and walk. The AbilityScore® is a clinician-administered, whole-child *assessment* used at a Pinnacle centre to build your child's individual baseline across many domains. One is a map; the other is a personal compass.

## How the two compare
Think of them as complementary, not competing:

- **What they measure.** The WHO-GMM covers six gross-motor milestones only (such as sitting without support, standing and walking alone). The AbilityScore® is broader — it considers communication, social-emotional, cognitive, motor and adaptive skills together.
- **What they're for.** The WHO-GMM gives a normal *window* — for example, walking alone typically emerges across a wide span of months, not a single deadline. It's a reassurance and screening reference. The AbilityScore® turns observation into a structured, individual picture you can track and act on.
- **How they're used.** The WHO-GMM is a chart anyone can read; the AbilityScore® is administered by a qualified Pinnacle clinician who interprets findings in the context of your child's full history.
- **What you get.** The WHO-GMM answers "is this within the typical range?" The AbilityScore® answers "what is my child's own baseline, and what's the plan?"

A child can fall outside a WHO window and still be perfectly fine — windows are wide for a reason. But a milestone that arrives late, or a pattern that feels off to you, is a good reason to move from the chart to a proper look.

## When to seek a closer look
If your child is at the far end of a WHO window — for instance not sitting with support by around 9 months or not walking by around 18 months — or if motor progress seems to stall or regress, it's worth a developmental check rather than waiting. Trust your instinct; you know your child best.

## The Pinnacle way
Developmental measurement supports care planning; diagnosis requires an appropriately qualified healthcare professional., under the care of a qualified clinician — never from a chart or an online figure. The AbilityScore® is a clinician-administered structured assessment that measures your child against *their own* baseline across many domains, then guides a practical plan. Backed by 2.5 billion+ data points, 25 million+ therapy sessions and 700+ therapists across 70+ centres, our teams pair assessment with hands-on support such as [occupational therapy](https://www.pinnacleblooms.org/best-occupational-therapy-center-india-proven-improvement-rate) when gross-motor skills need a gentle boost. Learn how the measure works: [what the AbilityScore is and how it's calculated](/ask/what-is-the-abilityscore-and-how-is-it-calculated).

## Trusted sources
WHO Multicentre Growth Reference Study on windows of achievement for six gross motor milestones; WHO and Nurturing Care framework on early childhood development; CDC and HealthyChildren (AAP) developmental milestone guidance.

**Next step —** Move from a chart to a clear, personal picture. [Book an AbilityScore assessment](https://www.pinnacleblooms.org/enroll-autism-speech-aba-therapies-india) with a Pinnacle clinician for warm, practical next steps.

This is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.

## Sources
- WHO child growth standards and motor milestone windows: https://www.who.int/tools/child-growth-standards
- CDC developmental milestone guidance: https://www.cdc.gov/child-development
- HealthyChildren (AAP) on developmental milestones: https://www.healthychildren.org
- Nurturing Care framework for early childhood development: https://nurturing-care.org

## Connected topics and perspectives
- Assessments: https://pinnacleblooms.org/ask/assessments
- Parent: https://pinnacleblooms.org/ask/lens/stakeholder/parent
- Assessment: https://pinnacleblooms.org/ask/lens/intent/assessment
- Measure: https://pinnacleblooms.org/ask/lens/lifecycle/measure
- Screen: https://pinnacleblooms.org/ask/lens/route/screen
- Early Clarity: https://pinnacleblooms.org/ask/lens/empowerment/early_clarity

## Related question paths

### Understand the subject
- What is the WHO Windows of Achievement for Gross Motor Milestones (WHO-GMM)?: https://pinnacleblooms.org/ask/what-is-the-who-windows-of-achievement-for-gross-motor-milestones-who-gmm-and-what-does-it-assess
- At What Age Is the WHO-GMM Used for a Child?: https://pinnacleblooms.org/ask/at-what-age-is-the-who-gmm-developmental-assessment-used-for-a-child

### Understand assessment
- Should My Child Have a WHO-GMM Assessment?: https://pinnacleblooms.org/ask/should-my-child-have-a-who-gmm-assessment-and-what-does-it-involve
- When is the WHO-GMM indicated, and what are its strengths and limits?: https://pinnacleblooms.org/ask/when-is-the-who-gmm-indicated-and-what-are-its-strengths-and-limits-in-early-childhood
- How AbilityScore tracks progress in Gross Motor Delay: https://pinnacleblooms.org/ask/how-does-abilityscore-track-progress-in-a-child-with-gross-motor-delay
- How the GMFM Compares with the AbilityScore Assessment: https://pinnacleblooms.org/ask/how-does-the-gmfm-compare-with-the-abilityscore-developmental-assessment