Final answer:
In designing an EHR, a critical early step is to develop a data dictionary, which defines the characteristics of each data element.
Step-by-step explanation:
In designing an EHR (Electronic Health Record), a critical early step is to develop a data dictionary, in which the characteristics of each data element are defined. The data dictionary serves as a centralized repository that provides a detailed description of all the data elements that will be used in the EHR system.
For example, the data dictionary may define a data element called 'patient name' and specify that it should be a text field with a maximum length of 50 characters. It may also specify whether the field is required or optional, and provide additional constraints or criteria for the data element.
Developing a data dictionary helps ensure consistency and standardization in the design of an EHR system, as it defines the attributes and properties of each data element, guiding developers in implementing the system accurately and efficiently.