Under a system developed by Johns Hopkins University called adjusted clinical groups (ACGs) , ACGs are a comprehensive family of measurement tools designed to help explain and predict how health care resources are delivered and consumed. ACGs are based on building blocks called aggregated diagnosis groups (ADGs). ADGs are a grouping of diagnosis codes that are similar in terms of severity and likelihood of persistence of the health condition over time. There are two categories of ADGs, ambulatory diagnostic groups–major diagnostic category (ADG-MDC) and ambulatory diagnostic groups–hospital dominant (ADG-HosDom).