An EHR extends the notion of an EMR to include the concept of cross-enterprise data sharing. Thus, an EHR typically contains subsets of EMR data from several healthcare institutions and enterprises; the information contributed to the EHR may vary depending on the individual institutions’ policies. An EHR can only be assembled if the participating institutions or enterprises all have EMR systems in place and are able to exchange data using standardized data transmission coding and messaging formats. An EHR system for recording, retrieving, and manipulating information should possess the following capabilities:

Longitudinal collection of patients’ electronic healthcare information ◾

Results management ◾

Order entry and management ◾

Immediate electronic access to an individual’s or a population’s information ◾

Electronic communication and connectivity ◾

Provision of knowledge and decision support to enhance patient care quality, safety, and ◾ effi ciency

Administrative process support ◾

Healthcare delivery process support ◾

Population health reporting and management ◾

Since a patient’s clinical healthcare information stored in an EHR system is usually generated by multiple healthcare institutions or enterprises at various times, it is likely to include multiple sets of data regarding patient demographics, medical history, medications, medical problems, allergies, vital signs, radiology reports, and laboratory reports. When reviewed over time, a patient’s EHR provides a longitudinal history of the patient’s health and of the healthcare services the patient has received. After each healthcare service is delivered, the appropriate data are collected and stored, and all downstream users can utilize the information to avoid redundant or inconsistent data collection. In addition to improving patient safety and continuity of patient care, EHRs also

contribute to public health improvement and healthcare cost control. Figure 11.1 shows a screen shot of the opening page of an enterprise EHR system with many different functionalities.