Rising to the challenge of defining and operationalising multimorbidity in a UK hospital setting: the ADMISSION research collaborative

Abstract

Key summary pointsAimTo propose a set of principles that can be used to select long-term conditions when studying multimorbidity in hospitalised patients and apply these principles to identify a list of conditions.FindingsWe have outlined a list of principles and applied these to identify a list of 60 long-term conditions that can be utilised when conducting research on multimorbidity in hospitalised patients in the UK and other countries with similar population health profiles.We have mapped this list of 60 conditions to the International Classification of Diseases 10th revision (ICD-10) codes, drawing on clinical and coding expertise, to facilitate consistency in the operationalisation of this list.MessageOur work addresses the need for greater transparency and consistency in the approach to the definition of multimorbidity and provides clear recommendations for those conducting research on multimorbidity in the hospital context.