Principles of Health Informatics: Communication systems in healthcare. Last delivered in 2023. All educational material listed or linked to on these pages in relation to King's College London may be provided for reference only, and therefore does not necessarily reflect the current course content.

1. Lecture 13: Communication systems in
healthcare
Dr. Martin Chapman
Principles of Health Informatics (7MPE1000). https://martinchapman.co.uk/teaching

2. Recall: Data channels
In Lecture 3 we looked at the concept of communication in
healthcare.
We (mostly) thought about communication between two people
engaged in a conversation in person. This might be a doctor
communicating with a patient, or two clinicians communicating about
a patient’s care.
We saw that good communication is important for intervention
delivery.

3. Communication systems
In this lecture, we will consider remote communication, which is,
consequently, facilitated by technology.
Specifically, we will consider the different components of a
communication system – the processes and tools that support remote
communication – each of which is a variable the selection of which
also impacts the efficacy of interventions.

4. Lecture structure
Communication system variables:
1. Communication devices: we need to select the right
communication device
2. Communication services: we need to select the right
communication service (defined by a chosen interaction mode, a
communication channel and communication media).
3. Message structure: we need to select a consistent and suitable
structure for our communications.
4. Communication policy: we need a communication policy that can
facilitate data access.
There are more variables,
but these are the key ones.

5. Learning outcomes
1. To understand different types of communication devices.
2. To understand (at a high level) different types of communication
services. More in Lecture 14.
3. To understand the need for, and example of, different health
message exchange standards.
4. To understand the role of policies in communication and data
transfer.
It all comes back to interventions…
To understand how all of the above impact intervention delivery.

6. 1. Communication devices

7. Communication devices
Communication between parties can occur using a number of
different devices:
First, a simple variable…
Smartphone Portable Computer Tablet Wearables Augmented reality

8. It all comes back to interventions…
Having the right device can ensure proper interventions.
If you can’t read an X-ray
properly, you can’t
intervene

9. 2. Communication services

10. Communication services
We can broadly define communication services as the means by which
data is transferred electronically between devices.
They are thus a core part of a communication system.
In this lecture, we will briefly consider five different services: voice, email
and text messages, mobile applications, video and social media.
Lecture 14 will explore in more detail the application of each of these
services to healthcare and intervention delivery.

11. Preamble: Interaction modes and channels
Each communication service is defined by a particular interaction
mode, and, in turn, a particular channel.
We saw one example of different time, different place (mode)
asynchronous (and one-way) communication (channel) in Lecture 3:
Consequently, these
channels are subject to
disruption and have
capacity, as we saw in
Lecture 3.
We noted this was problematic in respect of successful communication, and this still
remains true; it is hard to ensure the receiver knows a message has arrived.
X=1;
Y=2

12. Preamble: Interaction modes and channels
A slight variant on the interaction mode and channel seen in the
previous slide is different time, same place, asynchronous (one-way)
communication, which better ensures receipt by the receiver.
We can also have same time, different place, synchronous two-way
communication:
If this were synchronous one-way communication,
it would be something like a broadcast
Data flows backwards and forwards
across this channel

13. Preamble: Communication media
Each service is further defined by the type of media they use.
In this context we understand media, or medium, to mean the
communication medium used between the communicating parties, or
the form of messages.
Examples include voice, video or data.
Now to our services…

14. Communication services: Voice
Voice services can be either synchronous (e.g.
telephone calls) or asynchronous (e.g. voicemail).
Voice is, naturally, the primary communication
medium.
Services can connect one or more human parties,
but can also connect humans to computers via
automated conversations.
We consider each service in the
context of interaction mode,
channel and media.

15. Communication services: Email and text messages
Both involve sending short text-based messages, with the
latter (more like to come) from mobile devices. As such
they are mostly considered to be asynchronous services,
but text exchanges can have a real-time feel.
The communication medium can vary from text data
(standard) to richer data including voice and video (e.g.
rich media annotations through text services).
Both can come from humans, or be automated (e.g.
natural disaster warnings).

16. Communication services: Mobile applications
A variant on text-based services, with the channel
between the client (the application) and the server
(e.g. the company owning the application)
facilitating synchronous and asynchronous
communication (e.g. instant messaging).
Equally rich communication media are employed.
Can also be automated (e.g. notifications).
NB. Often not recognised,
but feels like it needs a
dedicated category

17. Communication services: Video services
Video services are typically considered to be
synchronous. Often supported by Internet-
based services (see previous slide).
Video is, naturally (again), the primary
medium.
Can also support the depiction of shared
work objects (e.g. screen sharing), emulating
a physical environment.

18. Communication services: Social media
A diverse collection of information
and communication services, which
are typically asynchronous.
A variety of media can be used to
communicate (data (text), video,
etc.).
Much more in Lecture 14.

19. Distribution modes
In addition to being categorised by interaction mode, channel and
medium, each of these services can also be categorised by the way in
which they distribute messages.
There are a number of distribution modes:
(1) ‘Peer-to-peer’: Messages are sent from one individual to only one
other.
(2) Narrowcasting: Sending a message to a few individuals.
(3) Broadcasting: Sending a message to a large number of individuals.

20. It all comes back to interventions…
Having the right device can ensure proper interventions.
Lecture 14 will explore the types of interventions different
communication services can support.

21. 3. Message structure

22. Recall: Structure
In Lecture 3 we talked a lot about the importance of good structure
in communications.
We saw how organising communicated data helps with interpretation
by the receiver, and considered some basic organisation mechanisms.

23. Messaging Standards
Within larger technology-based communication systems where the
complexity of the data shared grows, more elaborate structures are
required to ensure consistent representation of data and ease of
interpretation by a receiver.
These message structures are included in, and governed by, what we
call messaging standards.
Messaging standards also include protocols.

24. Aside: Machine-to-machine communication
We’ve mostly been considering person-to-person communication, but
we can also consider machine-to-machine communication:
This further motivates the need for (health) standards, as machines
need an explicit specification of the structure of data they are going
to receive.

25. Aside: Communication protocols
Machines also need an explicit specification of how to communicate.
Such a specification is given by something known as a
communication protocol, which are a set of rules that enable
communication to occur.
We encounter simple non-technical protocols all the time.
Shaking hands when first meeting someone before starting a
conversation is a good example.
We’ve also discussed protocols in
the context of guidelines as ‘the
way in which things should be
done’, which is not dissimilar to
this definition.

26. Aside: Communication protocols
When COVID arrived, this protocol had to
change for safety reasons, and (as you may
have experienced) this often resulted in
situations where the start of a conversation
felt strained or unusual.
Similarly, if one person extended their hand
and another didn’t this showed different
protocols were being observed.

27. Aside: Communication protocols and the Internet
More technical communication protocols – those used by machines –
include the protocols found for communicating through the internet.
Because communication through the internet relies on coordinating
lots of different parts of the data (e.g. its technical form, in bits and
bytes, as well as the actual high-level data itself), these protocols are
layered.
Protocols at higher layers do not need to be concerned about the
communication processes handled by lower layers, they can just
operate knowing these will be taken care of.

28. Aside: Communication protocols and the Internet
The International
Organization for
Standardization
(ISO)
Open System
Interconnection
(OSI) model
High-level data
Bits and bytes

29. Health Messaging Standards
In health, there are a number of different messaging standards.
In the next few slides we will look at one particular example, Health Level
7 (HL7) (Version 2.5).
Note that the ‘7’ here indicates that the standard is designed to target
(in, for example, the protocol(s) it includes), the application layer of the
ISO OSI model.
In other words, it is not a low-level standard dictating the transfer of bits
and bytes, but instead considers data exchange, which includes message
structure.

30. HL7 Structure
Each message sent under the HL7 standard is one of a number of distinct
types (e.g. a patient admission message (ADT), which may be sent from
one system to another when, for example, a patient enters secondary care).
Depending on its type, a message has to contain certain segments, each of
which communicates something about the event that triggered the message
(e.g. details of the patient being admitted to hospital).
Each segment in turn contains fields (such as a patient’s name), which in
turn can be broken into components (such as firstname and surname)

31. HL7 Structure
Over the next few slides we will construct an HL7 message using this structure.

32. Recall: Programming code
Over the next few slides, I shall reinforce some of the ideas I show
using programming code.
Programming code represents a series of steps to solve a problem.
If this is ultimately more confusing, you are welcome to skip these
slides.

33. HL7 Structure: Message
from hl7apy.core import Message
m = Message("ADT_A01");
First, we use our code to
construct a message

34. HL7 Structure: Segment
# Create a patient segment
from hl7apy.core import Segment
pid = Segment("PID");
Then we construct a
patient segment.
HL7 documentation tells
us the code we need to
use for this (PID).

35. HL7 Structure: Field
# Add a patient name field
from hl7apy.core import Field
pid_5 = Field("PID_5");
HL7 documentation tells us
the number we need for this
field (patient name)
Next we construct a patient
name field.

36. HL7 Structure: Component
# Add a family name component to the
patient name field
pid_5.pid_5_1 = 'CHAPMAN'
# Add a given name component to the
patient name field
pid_5.pid_5_2 = 'MARTIN'
# Add a prefix component to the patient
name field
pid_5.pid_5_5 = 'DR'
Finally, we add three components to
our patient name field.
We once again consult the
documentation for the
number of each component.

37. HL7 Structure: Message
# Combine everything together:
pid.add(pid_5);
m.add(pid);
print(m.to_er7())
PID| | | | |CHAPMAN^MARTIN^^^DR| | | | |
5th position
1st, 2nd and 5th positions
Pipes (|) delimit fields
and carets (^) delimit
components.
We call this ER7
encoding.

38. Other health standards
Later versions of HL7 (e.g. Version 3). Use
Extensible Markup Language (XML) instead
of ER7 encoding.
HL7’s Fast Healthcare Interoperability
Resources (FHIR) specification offers a
lightweight alternative to their extensive base
HL7 specification.
Key medical entities are represented as
individual resources, specified in a manner
that makes them easy to implement (e.g. as
Javascript Object Notation (JSON)).
{
"Patient": {
"name": {
"given": "Martin",
"family": "Chapman"
}
}
}

39. What about semantic interoperability?
You’re probably thinking there are lots of
overlaps here with data models and
terminologies, and you are correct.
Standards provide syntactic structure to
our communications (i.e. they are a
grammar), while terminologies provide
semantic information needed to actually
understand the content
See Lectures 11 and 12.

40. Aside: The semantic web
Regular web pages are designed to be read by humans, not by
machines.
The semantic web initiative aims to add machine-readable
annotations to web pages in order to enable intelligent software
agents to interpret data on the internet.
<div vocab="https://schema.org/" typeof="Person">
<span property="name">Martin Chapman</span>
</div>
Regular web
content
Semantic web
content

41. Standards: Beyond syntax and semantics
As we’ve seen, standards define the syntax (structure) of a message
and the semantics (intended meanings) of a message, but can also
go a step further, allowing systems to formally describe the
functionality that will be performed when a message is received (an
interface).
With these descriptions, systems become substitutable, because
another system can be plugged in that adopts the same description.

42. Standards: Beyond syntax and semantics
This is the principle behind the Substitutable Medical Apps Reusable
Technologies (SMART) platform.
‘I promise to
calculate risk
and return a %’
‘I promise to
calculate risk and
return a % too’
If two external
systems both
promise to calculate
risk, and return the
same type of result,
an EHR is agnostic
to which is used, and
it is easy to switch
between them

43. It all comes back to interventions…
Having the right device can ensure proper interventions.
Lecture 14 will explore the types of interventions different
communication services can support.
Not just having a standard but having the right one that efficiently
communicates health data in a given context can improve the quality
of intervention delivery.

44. 4. Communication policy

45. Communication policy
In the previous section we saw how lots of the data shared in a
health communication system is sensitive, e.g. patient data.
When communicating at scale, there are lots of parties involved (e.g.
a range of clinicians working at different hospitals), and thus lots of
people to whom this data might be sent or who might have access
to this data.
Therefore, our final component (variable) of a communication
system is who is allowed to receive and access this sensitive data.
Such a decision is captured in a communication policy.

46. Consent models
The choice about who has access to sensitive patient data remains
(typically) with the patient themselves.
A patient can choose from a number of different models, which in
turn guides the communication (often referred to as an access
control) policy:

47. Consent models
General
consent
General
consent with
denials
Parts of the record, or
to particular individuals
Send specific data to
a diagnostic service,
for example
General denial
with specific
consent
General
denial

48. Patient data: Opt-in vs. opt-out
An ongoing debate in many health
communities is whether patient
records should be shared by default
(e.g. at the national level).
The UK NHS does (to the best of my
knowledge), despite opposition, still
operate an opt-out policy.

49. Aside: Public key infrastructure (PKI)
Underpinning our consent policy are the security mechanisms that
stop individuals without authorisation from viewing information they
shouldn’t.
The concept of encryption (scrambling data), specifically keys and
the infrastructure needed to share them, plays a significant role here.

50. Aside: Public key infrastructure (PKI)
A clever key pair (basically just a string of characters in two files) is
generated (public and private) such that only the private key can
unencrypt (unscramble) things encrypted by the public key.
But there is no way to work out the private key from the public one,
so the public key can be shared to allow others to encrypt things
only readable by you.
This idea underpins
basically the entire
internet.

51. It all comes back to interventions…
Having the right device can ensure proper interventions.
Lecture 14 will explore the types of interventions different
communications services can support.
Not just having a standard but having the right one that efficiently
communicates health data in a given context can improve the quality
of intervention delivery.
Getting data consent right can ensure that a wide range of (digital)
interventions (e.g. those based on the EHR) are available if
appropriate.

52. Summary
Communication systems use technology to support remote
communications.
They are complex entities with multiple variables, including
communication devices and the services offered by those devices.
They also adopt standards for communication, and have procedural
elements such as policies.
In healthcare, getting these variables right is important in order to
properly facilitate interventions.

53. Epilogue: The wider goal and Health
Information Exchanges (HIE)

54. The wider goal and Health Information Exchanges
(HIE)
We’ve mostly considered the point-to-point communication of health
data in this lecture (between two or more parties), but what we
ultimately want to do is to scale this up to what we call health
information exchanges.
These exchanges could and can support communication between a
large number of health information providers, potentially separated by
large geographic distances, all with the goal of improving healthcare
at scale.
For a HIE, we have to make choices about how we structure the
network that connects each organisation:

55. HIE architectures
All information exchanged goes
through a central repository.
A central registry tells other
organisations where they need to
query for data.
Patient Health Records (PHR) are
owned and managed by patients
directly.

56. HIE architectures
Summary Care Records (SCR)
accessible centrally for
emergencies, more detailed data
available on request from other
organisations.
Health services store data of interest to
researchers in a Clinical Data Repository
(CDR). Research Data Repositories (RDRs)
provide researchers with access to this data,
and are periodically updated from the CDR
(e.g. for governance reasons).

57. References and Images
Enrico Coiera. Guide to Health Informatics (3rd ed.). CRC Press, 2015.
James Kurose and Keith Ross. Computer networking: a top-down approach. Pearson Education, 2010.
https://cgi.csc.liv.ac.uk/~gairing/COMP211/
https://www.nhs.uk/using-the-nhs/about-the-nhs/opt-out-of-sharing-your-health-records/
https://www.which.co.uk/reviews/mobile-phones/apple-iphone-11
https://www.britannica.com/technology/interpreter
https://www.microsoft.com/en-gb/d/surface-go-3/904H27D0CBWN/B5CR?OCID=AID2200065_seo_omc_goo
https://www.slashgear.com/withings-steel-hr-sport-review-fitness-smartwatch-21546865/

58. References and Images
https://www.furrows.co.uk/skoda/news/skoda-auto-looks-to-the-future/
https://en.wikipedia.org/wiki/Alice_and_Bob
https://onlinenotes1.wordpress.com/2019/03/07/006-explain-verbal-and-non-verbal-communication/
https://simpsons.fandom.com/wiki/AT-5000_Auto-dialer
https://www.superoffice.com/blog/follow-up-email/
https://play.google.com/store/apps/details?id=bbc.mobile.news.uk&hl=en_GB
https://www.access-board.gov/files/presentations/USAB_2021-01-13_Accessible_Virtual_Meetings.pdf
https://www.dreamhost.com/blog/50-greatest-things-on-the-web/
http://www.storagetwo.com/blog/2019/1/greenwich-kids-learn-to-code
https://www.riomed.com/electronic-patient-records-impact-on-healthcare-industry/