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Publication, Part of

National Child Measurement Programme, England 2019/20 School Year

Official statistics, National statistics

National Statistics
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The National Child Measurement Programme (NCMP) is a key element of the Government’s approach to tackling child obesity by annually measuring children in reception (aged 4–5 years) and year 6 (aged 10–11 years) in mainstream state-maintained schools in England. Independent and special schools are excluded.  See “Coverage” in annex B of the appendices for more details.

Child obesity is a good indicator of adult obesity which can lead to poor health outcomes. NCMP data enables local areas to plan services to tackle child obesity and monitor progress.

Local Authorities (LAs) in England measure children in mainstream state-maintained schools during the school year with the programme running between September and August each year to coincide with the academic year. In previous years, over a million children have been measured annually as part of the programme.

Impact of Covid-19 on NCMP

In March 2020, schools in England were closed to the majority of children in response to the covid-19 pandemic. With schools closed and school nursing teams being deployed to support the pandemic response, NCMP measurements could not take place.  Results letters for parents and proactive follow-up of children who had already been measured and identified as being outside the healthy weight range were also recommended to be deprioritised. 

NHS Digital were no longer expecting data to be uploaded to the NCMP IT system at that time however the system remained open as usual should local authorities and associated provider trusts have the resources to continue submitting data which had already been collected. Where possible LAs were asked to finalise their data submissions to NHS Digital by Wednesday 5th August 2020.

As detailed in the Methodology Change Notice (link below) the content of this national report this year differs to previous publications:

  • A large data quality section has been included, detailed work has been undertaken to assess any impacts of a partial year on national reporting.
  • A reduced set of national data tables and reporting has been included showing Body Mass Index (BMI) classification rates with breakdowns by: child age and sex; levels of deprivation and ethnicity. The report also contains comparisons over time where appropriate.
  • The impact of school closures varies considerably at Local Authority level and this is reflected in a reduced number of outputs being presented at LA level and further work undertaken to highlight how complete the data is for each LA.
  • The anonymised CSV file and guidance document will not be produced this year.

Significance and disclosure control

Comparisons between groups and over time have been statistically tested to determine whether differences are likely to be genuine (i.e. statistically significant) or the result of random natural variation. Only statistically significant differences have been described with terms such as “higher”, “lower”, “increase” or “decrease”. When a comparison does not show a statistically significant difference, this will be described using terms such as “similar to” or “the same as". 

New for 2019/20 is a change to the disclosure control rules used in the production and dissemination of the NCMP outputs. For full details of the new disclosure control process please refer to Appendices.

The report is accompanied by:

  • Data tables and data quality tables, including 95 per cent confidence intervals which should be considered when interpreting results.
  • Technical appendices with information on data collection, validation, confidence intervals, statistical testing and the methodology used for BMI classification rates.

Definitions used in the publication

The BMI classification of each child is derived by calculating the child’s BMI centile and classifying as follows:

  • BMI centile <=2: Underweight
  • BMI centile >2 and <85: Healthy weight
  • BMI centile >=85 and <95: Overweight
  • BMI centile >=95: Obese
  • BMI centile >=99.6 Severely obese. Note:  “Severely obese” is a subset of “Obese”. Children with a BMI centile of between 95 and 100 are classified as “Obese” and those with a BMI centile of between 99.6 and 100 are classified as “Severely obese”

This calculation uses age and sex as well as height and weight to take into account different growth patterns in boys and girls at different ages. A child’s BMI centile is a measure of how far a child’s BMI is above or below the average BMI value for their age and sex in a reference population. The NCMP uses the British 1990 growth reference (UK90) to define the BMI classifications.  This approach is recommended by The National Institute for Health and Care Excellence (NICE). See “Calculation of prevalence” in annex B of the appendices for more details.

The prevalence of children in a BMI classification is calculated by dividing the number of children in that BMI classification by the total number of children and multiplying the result by 100.

Geographical analyses in this report are primarily based on the postcode of the child’s home address which is mapped to a lower super output area.  Some time series analyses use the school postcode as the child postcode was poorly populated in the early years of the NCMP and these are labelled in the report.

Last edited: 28 October 2020 2:52 pm