Background The weight of children is the cornerstone of their clinical management. It determines fluid quantities, drug dosages and defibrillation power, which are administered on a per kilogram basis. Gold standard care for all paediatric patients who attend hospital involves being weighed using scales. This is not possible in the out of hospital setting, where weight derives from a guidance table based upon age. No evidence exists to indicate if the page by age approach indicated in current ambulance guidelines meets the reference standard of 70% of estimations within 10% of actual weight and 95% within 20% of actual weight.

Methods We used a cross sectional study design and collected data from a convenience sample of children who attended the outpatient’s department of a major hospital in England between July and September 2019. All children aged between one and eleven years who were weighed were eligible for inclusion. Outcomes were to determine if the page by age approach meets the reference standard and to determine any implications for care.

Results Three hundred and forty-one children were included in this study. Each age group consisted of varying numbers of children. 50.5% (172/341) of the sample were female. Observed weights ranged from 8.28 to 82.70 kg (median 20.60 kg). The mean weight of girls versus boys was 24.69 kg and 23.39 kg respectively (95% CI -4.12–1.32, p=0.3123). Observed weights were greater than the page for age guidance in all age groups and the accuracy of this approach diminishes with age.

Conclusion Page by age weight guidance does not meet the reference standard. Most paediatric prehospital care is administered by age and not weight. In the absence of an accurate weight, ambulance clinicians should continue to use the page for age system, although the gold standard remains to use an accurate weight measurement.