Table 1.

Basic clinical element model (CEM) categories

Category	Definition	Example
Statement	A complete assertion about a particular aspect, a characteristic or condition of a patient	DiastolicBloodPressureMeas: a single statement model, where it captures the value of the DBP measurement
Panel	A common grouping of clinical observations. It is a collection of other statements or panels	BloodPressurePanel can contain items such as DiastolicBloodPressure and SystolicBloodPressure
Component	Is similar to a statement in CEM, except that it cannot be persisted alone in the EHR, but must be persisted as an internal part of another model with type such as Statement or Panel
Attribution	Declares the who, where, why, and when information regarding an action	The model BloodPressurePanel has an attribution called ‘Observed’, which describes when, who, where, and why the blood pressure measurement was obtained
Qualifiers	Is used to add useful information to an instance but does not change the meaning of the data or items of the instance	BodyPosition of HeartRateMeas is a qualifier. In this case, whether the patient was sitting or standing during the measurement does not affect the meaning of the measurement itself
Modifier	Alters the meaning of the instance	Subject of model HeartRateMeas is a modifier. In this model, the subject changes the semantic interpretation of the measurement

DBP, diastolic blood pressure; EHR, electronic health records.