Continua: An Interoperable Personal Healthcare Ecosystem

MOBILE AND UBIQUITOUS SYSTEMS

www.computer.org/pervasive

Continua: An Interoperable
Personal Healthcare Ecosystem

Randy Carroll, Rick Cnossen, Mark Schnell, and David Simons
Vol. 6, No. 4

October–December 2007

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Standards & Emerging Technologies

Editor: Sumi Helal ■ University of Florida ■ [email protected]

Continua: An Interoperable
Personal Healthcare Ecosystem

Randy Carroll, Rick Cnossen, Mark Schnell, and David Simons

T he healthcare industry must im- • health and fitness: expanding per- • Can Continua member companies
prove its delivery methods and sonal health and wellness to where participate in the SDO?
reduce costs to address current and you live and play.
anticipated needs (see the “Healthcare • How well is the standard harmonized
Needs” sidebar). Various technologies The process Continua uses to develop with related domain standards?
could help by extending treatment and its interoperability guidelines is centered
care beyond traditional clinical settings on the use of industry standards. It • What are the specification access and
into personal and home settings. How- starts by evaluating member-submitted control mechanisms?
ever, creating such a personal telehealth use cases about interoperability prob-
ecosystem will require interoperability. lems related to one of the three focus • What is the associated intellectual-
Device connectivity to enterprise serv- areas. It then collapses the submittals property model?
ices is currently very proprietary.
Creating such a personal • Is there tool support?
In an effort to develop interoper- • What is the level of adoption and
ability guidelines for the emerging per- telehealth ecosystem will
sonal telehealth ecosystem, we formed maturity?
the Continua Health Alliance (www. require interoperability.
continuaalliance.org), an international Once Continua selects the candidate
alliance of more than 133 companies. Device connectivity to standards, it compares them against the
The guidelines will be based on a com- requirements to identify and address any
prehensive set of industry standards, enterprise services is gaps.
which will serve as a blueprint for inte-
grating a product into the ecosystem. currently very proprietary. Ultimately, the interoperability guide-
lines will define profiles over the stan-
INTEROPERABILITY THROUGH into a consolidated, generalized list of dards and serve as a basis for product
INDUSTRY STANDARDS use cases. Continua uses this list to pri- certification. To ensure compatibility,
oritize capabilities, interfaces, and Continua is establishing a certification
Figure 1 gives an example overview devices and then derives the desired and testing program that will include a
of a typical ecosystem of personal tele- functionality and requirements for the detailed set of test specifications and
health devices and services. Continua next version of the guidelines. automated testing tools so that candidate
aims to enable the alignment of differ- vendors can verify compliance. Addi-
ent vendors and domains, focusing on After this, Continua canvasses the tionally, interoperability events will en-
healthcare industry for existing standard sure that products from different vendors
• disease management: managing a development organizations (SDOs) and work together. A product that passes the
chronic disease outside of a clinical standards that best satisfy questions certification and testing program will
setting, such as receive certification and can display the
Continua interoperability logo.
• aging independently: using technol- • How well do the standards address the
ogy and services to live in your own capabilities in the selected use cases? The ecosystem also touches on other
home longer, and crucial areas. For example, Continua has
• Does the SDO have international been collecting trial data from the US and
standards or a path to generate them? Europe for the past five years to demon-
strate the benefits of the interoperable
healthcare ecosystem to insurance pro-

90 PERVASIVE computing Published by the IEEE Computer Society ■ 1536-1268/07/$25.00 © 2007 IEEE

Sensors Connectivity Aggregation and computation Services

Weight Zigbee PC Healthcare
scale Bluetooth provider
Home Network (Plain old telephone service, Cellular, Broadband) service
sensing & Blood Z Wave Personal
presure USB health Disease
control system management
Glucose
Bed/chair meter Medical Implant Cell service
sensors Commnunications Service/ phone
Pulse Diet or
Implant oximeter Medical Electronic Set top box fitness
monitors Data Service service
Spirometer Ethernet
Baby Personal
monitors Medication Wi-Fi health record
tracking
Personal service
Emergency Pedometer
Response Implant
Fitness monitoring
System equipment
service
Consumer
electronics Homeplug

Aggregator

Figure 1. A typical personal telehealth ecosystem.

viders. It’s also facilitating government puter, cell phone, or monitoring hub, to (LAN-IF) connects an application-
and insurance reimbursement discussions a PAN device, which is either a sensor or hosting device to a LAN device. This de-
to ensure that the economics of the sys- an actuator. (A sensor might be a glu- vice aggregates and shares (though a
tem work for all concerned. cose meter, weight scale, pedometer, network) the bound PAN devices’ in-
heart-rate monitor, or carbon monox- formation (this is often referred to as a
THE REFERENCE ide detector. The actuator could be a proxy function). A LAN device can also
ARCHITECTURE device that can turn on or off a light, implement sensor and actuator func-
shut off the gas in an emergency, output tionality directly. This means that the
The Continua End-to-End (E2E) text, or set off an alarm.) The PAN-IF LAN-IF upper layers can support the
Reference Architecture gives a high- has both a lower-layers component same device data model as the PAN-IF
level architectural view of the Con- (encompassing the classic open-systems- upper layers (that is, the ISO/IEEE
tinua ecosystem, including its topology interconnection layers 1–4) and an 11073-20601 data model). Using the
constraints (see figure 2). The distrib- upper-layers component (encompassing same device data model, regardless of
uted-systems architecture breaks down the classic OSI layers 5–7). the underlying lower-layers communi-
its functionality into five reference- cations mechanism, is a key interoper-
device classes and four network in- Example instantiations of the PAN-IF ability feature. Continua aims to base
terfaces that connect the devices to a lower layers include both wired and wire- the LAN-IF lower layers on Internet
reference topology. The network inter- less links (such as USB- and Bluetooth- Protocol technology to enable differ-
faces are at the center of Continua’s based technologies). The PAN-IF upper ent IP-centric communications tech-
interoperability goals and are the crux layers are implemented using the nologies (such as Ethernet and Wi-Fi
of the test and certification targets for ISO/IEEE 11073-20601 Optimized Ex- technologies).
candidate devices. change Protocol, which leverages work
from the ISO/IEEE 11073 Medical De- The Wide Area Network Interface
The Peripheral Area Network Inter- vice Communications working group. (WAN-IF) connects an application-
face (PAN-IF) connects an application- hosting device to one or more WAN
hosting device, such as a personal com- The Local Area Network Interface

OCTOBER–DECEMBER 2007 PERVASIVE computing 91

STANDARDS & EMERGING TECHNOLOGIES

STANDARDS & EMERGING TECHNOLOGIES

HEALTHCARE NEEDS

Acute diseases and conditions are often treatable owing to the ad- • More than 1 billion people in the world are overweight, and at least
vancement of healthcare techniques. People are now living longer, so 300 million of those are clinically obese.5
we’re seeing a corresponding rise in chronic diseases:
• Every year, more than 2 million deaths worldwide are attributable
• Over 600 million people worldwide have chronic diseases.1 to physical inactivity. (See www.stirlingmedical.com/education/
• According to the American Diabetes Association, in the US alone, statistics.)

20.8 million children and adults—7.0 percent of the population— • In 2005, the World Health Organization reported that it expects
have diabetes (see www.diabetes.org/about-diabetes.jsp). An addi- more than 2.3 billion to be overweight by 2015 (see www.who.int/
tional 54 million people have prediabetes (see www.diabetes.org/ mediacentre/factsheets/fs311/en).
pre-diabetes.jsp).
• Spending on chronic diseases is expected to increase from $500 bil- We need to prevent future health risks by engaging citizens in a
lion a year to $685 billion by 2020.1 healthy and balanced lifestyle through challenging self-health man-
agement and fitness solutions.

Therefore, we need to exploit technological advances to reduce REFERENCES
costs and improve quality of life.
1. P. Puska, C. Nishida, and D. Porter, “Obesity and Overweight,” World Health
Furthermore, with the Baby Boomer generation, we have an Organization, 2003; www.who.int/hpr/NPH/docs/gs_obesity.pdf.
aging population that requires escalating levels of assistance and
medical intervention: 2. What Works: Healing the Healthcare Staffing Shortage, Pricewaterhouse-
Coopers Health Research Inst., 2007.
• Globally, the number of people age 60 and older was 600 million in
the year 2000.2 3. World Population Ageing 1950-2050, Dept. of Economic and Social Af-
fairs, United Nations, 2001; www.un.org/esa/population/publications/
• By 2020, the over-65 population will double; it will triple by 2050.3 worldageing19502050.
• By 2020, the shortage of registered nurses required could reach 1
4. “Global Population Composition,” Global Population Profile: 2002, US Cen-
million.4 sus Bureau, Int’l Population Reports WP/02, 2004, pp. 31–52; www.census.
gov/ipc/prod/wp02/wp-02004.pdf.
So, we need to enable the elderly to live independently as long as pos-
sible (aging in place), with the peace of mind that assistance from their 5. Health Resources and Services Administration, What Is Behind HRSA’s Proj-
caregiver group (family, friends, neighbors, and professionals) is in reach ected Supply, Demand, and Shortage of Registered Nurses?, 2004; ftp://ftp.
when needed. hrsa.gov/bhpr/workforce/behindshortage.pdf.

Another pressing healthcare issue relates to obesity and physical
inactivity:

devices. A typical WAN device imple- EDGE [Enhanced Data Rates for GSM aged and operated by a traditional
ments a managed-network-based ser- Evolution]). Again, the sharable, ex- healthcare service provider. (For exam-
vice. It collects information and hosts changeable device data model is the ple, an electronic-health-records system
a wide range of value-adding services key component of the interoperable that a hospital or healthcare system
(for example, a health- or fitness-mon- Continua ecosystem. manages and operates). The xHRN-IF
itoring service hosted on a network- lets multiple enterprise healthcare enti-
based server). The WAN-IF upper lay- The Electronic/Personal Health Rec- ties exchange personal health informa-
ers use a device data model that’s ords Network Interface (xHRN-IF) en- tion. The corresponding health-record
compatible with the LAN-IF upper ables patient-centric data communica- systems have existing industry-standard
layers’ device data model. Continua tions between a WAN device and a information models that likely differ
also plans to base the WAN-IF lower health-record device, typically at the from the Continua WAN device. This
layers on IP technology to enable IP- boundary of the personal telehealth interface describes how healthcare enti-
centric communications technologies ecosystem. This is in contrast to the ties can transform the data so that all
(such as xDSL, DOCSIS [Data over Ca- other interfaces, which support device- parts of the larger healthcare systems
ble Service Interface Specifications], centric data communications between can collaborate.
PPP/POTS [Point-to-Point Protocol/ an application-hosting device and
Plain old telephone service], GPRS other Continua devices. The typical All of these Continua interfaces will
[General Packet Radio Service], and xHRN device implements a health- have associated guideline specifications
record database or other system, man- and test suites. However, especially in

92 PERVASIVE computing www.computer.org/pervasive

STANDARDS & EMERGING TECHNOLOGIES

the short term, Continua can’t encom- PAN device Application-hosting WAN device Health
pass all the communications interfaces device record device
that various vendors bring to the mar-
ket using existing or emerging propri- Composite device PAN Interface xHRN Interface
etary or open technologies. So, we rec- WAN Interface
ognize that noncertified interfaces will LAN device
exist in the personal telehealth ecosys- Composite device LAN Interface
tem that aren’t part of the Continua ref-
erence architecture. However, the archi- Figure 2. The Continua End-to-End reference architecture.
tecture will be able to bridge devices
with noncertified interfaces to the Con- PAN INTERFACE STANDARDS
tinua ecosystem using a PAN adapter
device or a LAN sharing device (see the
composite devices examples in figure
2). For example, an RF-receiver dongle
paired via a proprietary wireless com-
munications technology to a health
watch may, as a set, be certified as a
Continua PAN device. The architecture
can then plug that device into Continua
application-hosting devices.

THE BIG PICTURE Here are a few Peripheral Area Network Interface standards-development activities that are
To facilitate this large-scale opera- underway.

tion, Continua has created a series of Data and protocol
working groups, all governed by a
board of directors. These groups pur- The ISO/IEEE 11073 Personal Health Data Working Group is defining transport-independent
sue independent subgoals and tasks personal-health data and protocol standards. The group’s charter is to provide standards that
and periodically report to the larger address transport-independent application and information profiles between PAN devices and
Continua organization. The Technical application-hosting devices. Application and information profiles comprise exchange format,
Working Group has organized its work data representation, and terminology. The common exchange format should let different
into numerous subgroups, including domains share data. For more information, contact the group chair at [email protected].
one for each of the four interoperable
interfaces and one for each of the three Wireless transport
focus areas. It also has subgroups that
focus on some overarching subject, The Bluetooth SIG Medical Devices Working Group is tasked with enabling interoperability
such as the overall architecture or sys- between Bluetooth-enabled medical, health, and fitness devices, and systems that can aggre-
tem security and privacy. gate and perform operations on device data. (Such data could be from cellular phones, health
appliances, set-top boxes, or PCs.) This effort includes the development of a profile that allows
Much of the work is restricted to consumers to easily connect any two devices that support the medical device profile. Such
Continua’s members. However, an- devices have unique needs, and this working group aims to address those needs through fo-
other way to participate is to join the cused representation of the medical- and fitness-device industries. For more information, con-
corresponding SDOs, which also lets tact the group chair at [email protected].
you fully participate in the discussion
and construction of the bedrock stan- Wired transport
dards (for example, see the “PAN In-
terface Standards” sidebar). The USB-IF Personal Healthcare Device Working Group is tasked to enable personal health-
care devices to seamlessly interoperate with USB hosts. The group’s initial goal is to define a
C ontinua plans to complete its Ver- USB Personal Healthcare Device Class specification. The specification will enable health-related
sion One Guidelines in the first devices, such as blood pressure cuffs and exercise watches, to connect via USB to consumer
quarter of 2008. At the same time, it electronic products such as PCs and health appliances. Interoperability of health-related de-
will launch its certification and test- vices and consumer electronic products will facilitate the communication between a patient
ing program. These guidelines, tests, and a doctor, an individual and a fitness coach, or an elderly person and a remote caregiver.
and procedures will ensure interoper- For more information, contact the group chair at [email protected].

OCTOBER–DECEMBER 2007 PERVASIVE computing 93

STANDARDS & EMERGING TECHNOLOGIES

STANDARDS & EMERGING TECHNOLOGIES

http://dsonline.computer.org ability of the components within the
personal healthcare ecosystem. This
IEEE paves the way for new and innovative
products to radically improve health
DISTRIBUTED SYSTEMS and quality of life as well as eliminate
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by the IEEE Computer Society
Randy Carroll is a senior
Cluster Computing IEEE Distributed Systems software engineer for IBM at
Grid Computing Online brings you peer-reviewed Research Triangle Park,
where he works for a soft-
articles, expert-managed topic areas, ware standards and strategy
organization. Contact him at
detailed tutorials, and diverse depart- [email protected].

ments covering the latest news and de- Rick Cnossen leads a team in
Intel’s Digital Health Standards
velopments in this fast-growing field. & Policy Group that focuses
on personal health interoper-
Web Systems Log on to IEEE Distributed ability standards and ecosys-
Mobile & Pervasive Systems Online for tem-enabling activities. He’s
also chair of the Continua Health Alliance Techni-
cal Working Group and a lower-layer chair for the
ISO/IEEE 11073 Medical Device Communications
Working Group. Contact him at rick.a.cnossen@
intel.com.

Middleware Timely Industry Comprehensive Mark Schnell is a senior
Distributed Agents News Articles technical leader at Cisco Sys-
tem’s North Carolina RTP
Security Resources You campus, where he works
Parallel Processing Can Rely On with healthcare domain ex-
perts to identify the appro-
priate communications technologies to apply to
an interoperable healthcare ecosystem. Contact
him at [email protected].

Operating Systems David Simons is a senior
architect at Philips Re-
search Europe in the area of
healthcare systems archi-
tecture. Contact him at
[email protected];
http://david-simons.com.

94 PERVASIVE computing www.computer.org/pervasive