The wonderful thing about standards is that there are so many of them
to choose from.
The last chapter presents the interoperability challenges facing the electronic health
record (EHR) in general and the medications system speciﬁcally. How are the actors,
the disparate components presented in the previous chapters of this book, supposed
to play with others in the proverbial healthcare information technology sandbox?
The short answer is by adhering to standards and vocabularies.
Interoperability, standards, terminologies, and classiﬁcations are deﬁned. From
the organizations active in standardization in medicine, we identify the main
standards and vocabularies in HIT. The chapter is biased toward the U.S. mar-
ket, in lieu of the recently published Meaningful Use (MU) part of the American
Recovery and Reinvestment Act.
Next, we zoom in on the standards and vocabularies relevant to the domain
of this book as we identify the interoperability needs: workﬂows and data struc-
tures related to the Medications system.
In between, we brieﬂy touch, and only from an information technology
perspective, on philosophical issues of language, context, meaning, ambiguity,
and so on.
290 ◾ Electronic Health Record: A Systems Analysis of the Medications Domain
The raison d’etre, the whole reason, for IT existence is to enable information
sharing. This basic fact is sometimes forgotten in discussions about the higher,
noble roles of Healthcare Information Technology (HIT): improving healthcare
quality and containing the rising costs of providing care. But without informa-
tion sharing, higher goals cannot be achieved.
As deﬁned by the Institute of Electrical and Electronics Engineers (IEEE),
interoperability is “the ability of two or more systems or components to exchange
information and to use the information that has been exchanged” (1).
A meaningful information exchange between two entities necessitates that
both sender and receiver (be it human or machine) agree on a set of communi-
◾ The grammar of the language used
◾ The meaning of the words—the vocabulary, terminology assumed to be in
Interoperability has several capability levels as deﬁned by Tolk et al. (2) in the
Levels of Conceptual Interoperability Model (LCIM) (Table10.1). Engineers initially
published LCIM for the modeling and simulation domain (3), but LCIM can be
applied to other communication channels as well, such as humans or machines
No Interoperability → Technical → Lexical and Syntactic → Semantic →
Context → Dynamic → Conceptual
The LCIM shows that in order to achieve the level of semantic (language)
interoperability, the communicating entities need to achieve both lexical (terms)
and syntactical (grammar) interoperability as prerequisites. For the highest level
of conceptual interoperability (message meaning), the context, modeling assump-
tions, and constraints as well as the dynamics of workﬂow and processes must
be agreed on by the participating entities.
Open Systems Interconnection Model
How are machines communicating? How are different hardware conﬁgura-
tions, with disparate operating systems and software applications, interoperat-
ing? How does information hop over numerous and various machines, wired
and wireless media? How does the Web work? The answer is by adhering to
standards. The Open Systems Interconnection (OSI) model, developed by the
International Organization for Standardization (ISO) divides a communica-
tion system into layers (4) (Table10.2). Each layer has speciﬁc responsibilities,