Development and implementation of a paediatric dosing calculator integrated in the Dutch Paediatric Formulary

Calculation errors are the most common dosing errors in paediatrics. While health information technology has been advocated to improve patient safety, the broad implementation of computer-calculated dosing in the paediatric setting is delayed for the lack of computable, explicit and unambiguous paediatric dosing guidelines. The structured digital dosing guidelines of the Dutch Paediatric Formulary permitted the development of a paediatric dosing calculator that combines drug dosing recommendations of the formulary with patient variables. We took into account the European Union Medical Devices Directive (EEC 93/43) and international standards describing the requirements for the development and maintenance of medical software, the risk management in relation to medical devices and the application of usability engineering to medical devices. As key steps in the development and risk management of software, we first specified the intended use and primary operating functions, then identified potential failures and resolved failures by corrective measures. The paediatric dosing calculator calculates an individual dose based on specified patient characteristics and the dose recommendations provided in the formulary. This is a step-by-step process where a user first enters patient variables (date of birth, weight) and then selects drug variables (indication, route of administration). Based on the selected patient and drug variables, an individual dose is calculated. In addition, the calculated dose in weight units (grams, milligrams) can be converted to a volume-based dose (millilitres) of a fluid product. We successfully developed and implemented a dosing calculator in our national web-based Dutch Paediatric Formulary, which so far has been used more than 65,000 times monthly.