WHO Developmental Milestones

Original Editor - Evelin Milev Top Contributors - Evelin Milev, Kim Jackson and Amrita Patro


The WHO scale aims to link the growth of the child and the motor development in one single reference. The final version of the protocol includes six items: "Sitting without support", "Hands-and-knees crawling", "Standing with assistance", "Walking with assistance", "Standing alone", and "Walking alone". The WHO provides an important information about child's gross motor development in different cultural settings[1].

Intended Population

The WHO Motor Development assessment protocol has been designed to capture the gross motor development in the first two years of life in children from different cultural background, and therefore fill an existing gap in knowledge. The Motor Development Study took part in five countries (Ghana, Norway, India, Oman, and the United States) which aimed to analyse the relationship between physical growth and gross motor development in this culturally mixed cohort.

Although the study was conducted with children between 4 and 24 months of age the assessment could be used for patients from different age groups and serve as a baseline for more focused studies of both motor and cognitive development[1]. In some cases the scale is also used in combination with other outcome measure. An example is the Revised Hammersmith Scale (RHS) which follows on the physical abilities in patients with Spinal Muscular Atrophy[2].

Method of Use

The WHO milestone assessment consist of six items which were selected because they have been considered to be universal, fundamental, and simple to test and evaluate. However, when evaluating a milestone we should not only observe what a child does, but also how and with what level of development they do it[3].

The six items on the WHO milestone scale are listed below:

  1. Sitting without support
  2. Hands and knees crawling
  3. Standing with assistance
  4. Walking with assistance
  5. Standing alone
  6. Walking alone


The published article and all relevant references can be found here.


  1. 1.0 1.1 Wijnhoven, T. M., et al. (2004). "Assessment of gross motor development in the WHO Multicentre Growth Reference Study." Food Nutr Bull 25(1 Suppl): S37-45.
  2. Ramsey D, Scoto M, Mayhew A, Main M, Mazzone ES, Montes J, et al. (2017) Revised Hammersmith Scale for spinal muscular atrophy: A SMA specific clinical outcome assessment tool. PLoS ONE 12(2): e0172346. doi:10.1371/journal. pone.0172346
  3. Illingworth RS. The normal child: Some problems of the early years and their treatment, 1991