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G573(P) Improving ease and accuracy of centile calculations with a smartphone implementation of rcpch uk-who growth charts
  1. CJ Kelly
  1. Centre for the Developing Brain, King’s College London, London, UK


Context Improvement work performed while working as a paediatric trainee ST2 on a tertiary neonatal intensive care unit, neurosurgical ward and academic research department. Target audience: health professionals who calculate growth centiles on a regular basis.

Problem Calculating growth centiles and their trends are a crucial part of the general paediatric and neonatal assessment. However, due to the regular scarcity of paper charts and inconvenience of trying to find one on a busy ward, centiles are often overlooked. Even with a chart available for use, the manual plotting method gives broad estimates rather than exact numbers (i.e. 25–50th centile), which are not appropriate for research purposes.

Assessment of problem and analysis of its causes Working on a paediatric neurosurgical ward, the neurosurgical consultants complained that growth centiles were not being filled in consistently by junior doctors during clerking. A poll of fellow trainees agreed that an electronic version, available at the point of care, would be very beneficial. Problems with paper growth charts include lack of chart availability, time pressure, plotting inaccuracies, and inherent centile approximation due to threshold banding. Additionally, the calculation of corrected age for children and post menstrual ages for premature babies is commonly performed inaccurately.

A solution to this problem would need to combine improved accuracy with greater ease of calculation, providing a tool that staff could carry with them everywhere at work.

Intervention Creation of a smartphone app to calculate growth centiles for premature babies through to 18 year old children, using RCPCH UK-WHO data. The app also addresses the difficulty of calculating corrected ages by building this into the calculation.

Strategy for change The provisional app was circulated to a number of interested paediatricians, and very helpful feedback received from the NHS Hackday group. The app was also discussed with Prof Tim Cole (the creator of the original growth charts), who provided some very helpful feedback and suggestions for improvement.

The app was launched as a free download in October 2014 on iPhone and Android as a proof of concept via social media, and a significant amount of constructive feedback was received. An updated version is currently in progress, building in many of these suggestions.

Measurement of improvement The project is at an early stage, and no objective metrics of improvement have yet been collected. It is hoped that this will be possible after the launch of the final version.

Effects of changes The app is now being used in the research department at St Thomas’ to calculate accurate centiles for research participants at the Centre for the Developing Brain. Despite the deliberately local launch of the first version, the app has already been downloaded by 2,500 users. It is hoped that as the app gains adoption, the calculation of growth centiles in paediatric practice will become more widespread, with associated benefits to child health (Figure 1).

Lessons learnt I have learned about implementing a new tool in clinical practice, combined with gathering feedback and suggestions from a wide range of people to make the product as clinically useful as possible.

Message for others Creating a web/app-based tool for commonly-performed error-prone tasks appears to be an effective strategy to improve quality at the bedside. There are many resources available online to guide interested people through this process.

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