Can ICD-10 Z codes be used as proxy measures for ACE categories? – a proof of concept

Abstract

ABSTRACT Objective The landmark study by Felitti showed adverse childhood experiences (ACEs) influence future health outcomes. This paper looks at the routine data collected in a Child and Youth Mental Health Service (CYMHS) related to contextual factors in the International Classification of Diseases (ICD-10 Z codes) and seeks to identify proxies for the ten original ACEs categories. In the absence of routinely collected ACE categories, these ICD-10 Z codes which could potentially act as ACE proxies would be helpful for clinical understanding and service delivery. Method ICD-10 Z codes collected routinely from 2108 individuals were analysed to identify Z codes which might serve as proxies for the ACE categories. To understand whether these Z codes were used appropriately during service delivery to indicate ACE categories, randomly selected files of patients having at least one of the above Z codes in their list of diagnoses were reviewed. Subsequently, the associations between several Z codes (serving as ACE proxies), demographic factors, and clinical outcome measures were explored. Results Significant differences were observed in terms of the mean ACE score of patients when sex, Indigenous status and certain diagnostic groups were considered. Similarly, when patient groups having exposure to different numbers of ACEs were compared, significant differences were observed in outcome scores (HoNOSCA and CGAS). Conclusion There is evidence that certain Z codes, can act as ACE proxies. This suggests a possible utility of this method in studying other associations and possibly helping to tailor future therapeutic interventions.