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Content uploaded by Sujatha Alla
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All content in this area was uploaded by Sujatha Alla on Jun 29, 2018
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Proceedings of the 2018 IISE Annual Conference
K. Barker, D. Berry, C. Rainwater, eds.
Blockchain Technology in Electronic Healthcare Systems
Sujatha Alla, Leili Soltanisehat, Unal Tatar, and Omer Keskin
Engineering Management & Systems Engineering Department
Old Dominion University
Norfolk, VA 23529, USA
Abstract ID: 1913
The healthcare industry has been adopting innovative technologies that allow digitalization of health records and
automation of clinical processes. The need for interoperability across different departments in healthcare requires a
seamless data exchange inside the system. However, confidentiality and integrity of data are critical issues during the
process of sharing data across different authorized parties. Hundreds of millions of medical records have been
compromised in 2016 and the number increases. The emerging blockchain technology is a revolutionary mechanism,
which ensures data integrity and confidentiality inside any system. Some healthcare providers have been inclined to
implement blockchain technology as it presents a decentralized and encrypted way of storing and sharing information.
This emerging technology has a great potential to enhance the confidentiality and integrity of Electronic Health
Records. In this paper, we conducted a systematic literature review to find out the research gaps and future research
directions in blockchain technology in healthcare research. The literature is analyzed to find advantages, disadvantages
and challenges of adopting blockchain technology in healthcare from people, process technology perspectives.
Keywords
Blockchain Technology, Electronic Health Records, Information Security, Literature Review
1. Introduction
With the evolution of the Internet of Things (IoT) and abundance of health devices and health apps, a vast amount of
medical data are recorded and transferred every day. This large database of medical information needs management
regarding privacy, security, and availability. Hospitals and doctors need to access to the patient’s medical information
during the treatment process while ensuring security and privacy of sensitive information of patients as they share
them with hospitals and medical institutes. Additionally, according to the Health Insurance Portability and
Accountability Act, law enforcement and other specific public agencies may legally access health information. It is
estimated that as many as 150 to 400 individuals may access a person’s Electronic Health Records (EHR) [1]. Given
that the data is shared widely and stored in multiple places, securing it becomes a more significant issue. According
to the Ponemon Institute, in 2016, over 112 million medical records were compromised, and such data breach attacks
increased by 162% so far in 2017 [2].
Blockchain Technology introduced a financial application that has started a revolution in many fields including
healthcare information systems. Blockchain technology can provide a solution that not only helps to secure recording
and sharing of medical records but also to assure the privacy of each patient’s data by giving their medical data
ownership to the patients, themselves. In this study, we conducted a systematic literature review on blockchain
technology and healthcare research. In the following section, we reviewed the concepts of blockchain technology. The
third section is devoted to research methodology. Section four gives the systematic analysis of the selected papers in
research methodology and some research gap identified based on this analysis. The conclusion is given in section five.
2. Blockchain Technology
Blockchain technology is defined as distributed ledger technology, which records transactions in a secure, transparent,
decentralized, and efficient manner with low cost. The blockchain is the technology underlies bitcoin, which was
introduced by pseudonym Satoshi Nakamoto in 2008. In order to understand how blockchain works, first, it is better
to know the bitcoin mechanism. Bitcoin is a peer-to-peer, distributed, and decentralized digital currency. There is no
third party as a trusted intermediate in bitcoin transaction system, and anyone with bitcoin can participate in the
network, read, write to, and hold a copy of the transactions records [3].
Alla, Soltanisehat, Tatar, and Keskin
2.1. How Bitcoin Blockchain Works
There are two challenges of the transaction system without central control agency: (1) single point of failure and (2)
peer-to-peer double spending of the same digital asset like money. Blockchain technology solves this problem using
two mechanisms: hash-chain time-stamping and proof of work algorithm [4]. First, in order to verify each transaction,
it should be stored in each computation node in the network. All transactions are timestamped and distributed in the
network. Bitcoin blockchain exploits hash-chain as distributed timestamp mechanism to determine the possibility of
doing the transaction and maintaining a copy of transaction chain in every node [3]. Second, bitcoin blockchain uses
the reward and punishment mechanism for preventing any possible interruption or malicious transaction. Miners are
the participants who do the mining process in blockchain, i.e., creating new blocks with enclosed transactions list and
chaining them to the previous blocks. Figure.1 shows how blocks are created and chained together. Each block has
two important parts: (1) Content: a validated list of transactions. The transacted digital asset can be digital money
(e.g., Bitcoin, Ethereum) or any kind of data such as a school diploma, a medical record. (2) Header: which includes
metadata, such as (a) Block reference number to the content of the block, known as the hash root, (b) The time the
block was created known as timestamp, (c) A link back to the previous block, and (d) A random number (nonce)
which is added to the block address according to the proof of work algorithm [3].
In bitcoin blockchain system miners use proof of work protocol in order to find a new address for the new block with
specific properties. This property in bitcoin blockchain is a 32-bit crypto number with seventeen zero bit in the
beginning. Miners run this algorithm multiple times to get such a number by trying different random numbers (nonce).
After finding a new address for the new block, the miner updates the ledger and send it to the entire network. Then
the majority of the network should confirm the new block. This process is called proof of work or consensus in bitcoin
blockchain system. The mining process is difficult, time taking and costly, this prevents creating invalid and fraud
transactions. Therefore, bitcoin mechanism provides rewards for the miner who can add the new block first, as an
incentive to compensate the efforts and cost associated with the mining process [3]. Another benefit of using proof of
work consensus protocol is that it let blockchain to be immutable audit trails by chaining blocks together using a hash
function. Each block contains the hash value of the previous block’s header (Prev.Hash), and therefore if an attacker
tries to modify a block, all the upcoming blocks should be modified. Such a modification needs a high computation
power, time and cost. Even if the attacker succeeds to create the fraud chain of blocks, replacing it with the honest
chain requires the consensus of the majority of the nodes in the network. Thus, the bitcoin blockchain system is highly
secure against any modification and failure, and this comes from its specific structure [4].
Figure 1: Contents of each block in a sample blockchain
2.2. Blockchain Technology for Other Sectors
Although blockchain was first introduced for finance, there are many other applications, which has been developed
and implemented. Blockchain technology, as a horizontal technology, is revolutionizing the future of the transaction-
based exchange in different industries such as finance, insurance, telecommunication, and healthcare. According to
Melanie Swan, there are three phases of blockchain adoption: Blockchain 1.0 is the first development of blockchain
as a cryptocurrency, bitcoin. Blockchain 2.0 refers to smart contracts, financial records and tracking the ownership of
the properties inside the blockchain system. Blockchain 3.0 will come in science, medicine, and education [5].
2.3. Blockchain Technology for Healthcare
The idea of applying blockchain in healthcare comes out of the need for security and interoperability in healthcare.
With the evolution of IoT and abundance of health devices and mobile healthcare applications, a considerable amount
of medical data are recorded and transferred every day. This data traffic needs management regarding privacy and
security. Blockchain technology can provide a solution that not only helps to secure recording and sharing of medical
records but also assures the privacy of each patient’s data by giving the patients, their medical data ownership. Besides
the advantages of blockchain for healthcare management, its challenges should be met in advance [6].
Alla, Soltanisehat, Tatar, and Keskin
3. Research Methodology
The systematic literature review is selected as the methodology of this study. The aim of the systematic literature
review is identifying the previous research on the topic, which is blockchain for healthcare in our case, and then
defining the research gaps and future research directions. We firstly identified two research questions:
1. What are the research topics that have been studied on blockchain in healthcare? Through scrutinizing
all relevant papers in the literature, we built a comprehensive understanding of current research of blockchain
in healthcare domain. We also mentioned applications of blockchain technology in healthcare to comprehend
its current and potential impact.
2. What are the research gaps and future research directions in blockchain technology in healthcare
research? A systematic literature review facilitates the identification of challenges and limitations alongside
disadvantages of adopting blockchain technology, particularly in healthcare domain. The research gaps and
future research directions are based on the identified challenges, limitations, and disadvantages.
In order to find the academic papers, we needed keywords to query on scientific databases. Deciding on the appropriate
databases is the next step for running the keyword search. Identification of the relevant papers was made in three steps:
(1) Running keyword queries on academic databases, (2) Removing the irrelevant papers by manually reviewing the
meta-data, (3) Selecting the appropriate articles by reading the papers.
As the review subject is the application of blockchain technology to healthcare, we identified the keywords as
"blockchain," "healthcare," and "health care" for the search queries as shown in Table 1. Identification of relevant
scientific databases is also a challenge since the reviewed area is composed of two topics that are not directly related.
Blockchain is a concept that has foundations in computer science and applied mathematics while spreading over
various domains from finance to healthcare. Healthcare is already an established and broad area of research. To find
the all relevant papers, we searched the following major databases of information technology and healthcare: ACM
Digital Library, EBSCO, IEEE Xplore, ProQuest, ScienceDirect, Medline First Search, and Medline ProQuest.
Table 1. Results of queries in scientific databases
Keywords and Query
Database
"Blockchain" + "Healthcare" "Blockchain" + "Health care"
Total Number
of Reviewed
Search Result
Reviewed
Search Result
Reviewed
Papers
IEEE Xplore
6
6
0
0
6
ACM Digital Library
1
1
0
0
1
ScienceDirect
0
0
0
0
0
EBSCO
0
0
1
0 (irrelevant)
0
PLOS One
0
0
0
0
0
ProQuest
3
1 (duplicate)
1
0 (duplicate)
1
Medline ProQuest
1
0 (duplicate)
0
0
0
Medline First Search
2
1 (duplicate)
5
5
6
Total
13
9
7
5
14
The column, “search result,” gives the number of publications identified by the queries of only keywords field of the
databases. After we read the abstract of each paper to understand if it is relevant for further analysis. The column,
"reviewed," gives the number of papers obtained after this filtering study. Search queries yielded 20 papers, and the
manual reviews of papers decreased it to 19. The removal of duplications resulted in a set of 14. After scrutinizing all
these papers and eliminating those that do not fit the outlined criteria, we ended up with 14 studies for detailed analysis.
An initial analysis of the selected papers showed that three papers published in 2016 and others in 2017. The three
papers published in 2016 have been cited 55 times according to Google Scholar records. These show that the topic is
new and trending. Five of the selected papers are conference papers, and others are journal articles.
4. Systematic Analysis
In this section, we analyzed the selected 15 studies, identified and listed the advantages, disadvantages, and challenges
of employing blockchain technology in healthcare. For simplicity and clarity, we categorized them from the
perspective of people, process, and technology.
Alla, Soltanisehat, Tatar, and Keskin
4.1. People
Advantages: Blockchain technology can enable interoperable, unified and secured view and exchange of electronic
health records [7, 8]. Patients can own their medical records instead of storing this sensitive information separately on
the networks of various healthcare providers. Since the data is unified, any updates to the data are done globally. Up-
to-date data is available when it is needed [7]. Patients can also choose whom to share the data. Thus, control can be
oriented more towards the consumer while having balance with other important players in the system [7, 8].
Blockchain technology provides the authorities the ability to access health records when needed [9].
Disadvantages: Once the provider has a patient’s data, they could possess it permanently by any other means,
although the patient may not want it [10].
Challenges: Patients are not much aware of this new technology. Apparently, there would be confusion on where the
data would be stored and who can have access to this data [7].
4.2. Processes
Advantages: Security is a critical issue for healthcare processes. The blockchain technology can provide high tamper
resistance, hence vulnerable health data can be promised to be kept with high-level security [8]. Moreover, since the
health data from various sources can be stored on the distributed blockchain that does not rely on one central storage
facility, government and other organizations would be liberated from the liability of handling enormous amounts of
data [11, 12]. Blockchain has the potential for the automated validation of claims, verify eligibility verification, and
preauthorization that may increase the transparency, authenticity, efficiency, security of the process [13]. Because of
the transparency in the shared infrastructure a new confidence level would be attained among patients and medical
stakeholders [14] in addition to the increased security.
Research is another critical aspect of healthcare sector that blockchain technology can help. Its decentralized approach
to manage permissions, authorization, immutable audit trail, and to provide rapid and secure access to longitudinal
research data [4, 13]. For example, an organization, MedRec, proposes a mining model that allows medical researchers
and healthcare stakeholders to mine for aggregated medical data in the network [11, 12]. Blockchain technology may
enhance the development of drugs and medical devices and could reduce the production of counterfeit medicine and
clinical trials by decreasing the amount currently spent on confirmation by the third party [8, 11, 14]. Blockchain
technology can also help developing new hardware and software to improve healthcare processes. It can tackle the
problem of proper use and integration of new devices into the existing network that has sensitive health records[15].
Blockchain also offers to make healthcare processes easier and more robust. In blockchain, data is stored in a single
format and interconnected among various organizations, no matter at which place the health record was processed.
This reduces the complexities of maintaining and sharing EHRs [7]. Moreover, the possibility of human error and
processing times would be reduced because the system could minimize human involvement with data [8]. The features
such as robustness and availability provide the preservation of records by storing a whole copy of historical data record
on each node and making them available to access to the users at all times [4]. The origin of the assets is traceable,
thus the reusability and robustness of verified data increases. This is also referred as data provenance and is essential
for some healthcare processes such as insurance transactions [4]. It is also estimated that in the future, healthcare
application users may receive financial benefits for their data provided for medical research [14, 16].
Disadvantages: Blockchain technology also has some cons. There is still a great deal of hype and uncertainty about
this technology [5]. This causes issues about the legality of this technology (e.g., for access management) [7]. In order
to implement the changes to the current infrastructure required for this technology, it must be legally approved first.
Challenges: Several potential barriers exist concerning ethics and operational guidance, compliance with regulatory
requirements, and the technical barriers related to data storage and distribution [13, 15]. Determining the data sharing
conventions is one of these challenges. For example, it is a question to be answered how a patient can choose which
data to share and to whom. Patient, as the owner of the data, must authorize a healthcare provider to access the data.
If for any reason, the patient is not able to do that, it is unclear who has the authorization to do so on behalf of a patient.
It is also not clear that what amount of health data need to be stored online and if the data can be shared with one
another indefinitely or for a fixed amount of time [7].
Alla, Soltanisehat, Tatar, and Keskin
While data within the blockchain can be de-identified and encrypted, the data security still may be vulnerable due to
poorly maintained or outdated codes in an incident involving a decentralized autonomous organization [8, 13]. Even
though a user is anonymized by a hash value, the user can still be identified through inspection and analysis of the
publicly available transaction information, and therefore provides only pseudonymity instead of anonymity [4]. While
blockchain can prevent data block fraud, it remains a challenge to guarantee the identity and authenticity of the
informant and stakeholders [4]. The transparency aspects make it difficult to protect data against malicious traffic
analysis while maintaining accountability and transaction privacy [17].
Transition to the blockchain technology in healthcare processes have some other problems. A sufficient amount of
training is required for healthcare providers and patients. Users have to be trained on how to design and manage the
distributed controllers and network functions to ensure vertical and horizontal scalability, and how to autonomously
orchestrate network functions and services across the softwarized middleware [17]. Additionally, the transition may
take a long time, and during the transition, there may be some issues in the processes. For example, currently, for
patients capability of self-reporting the symptoms of their sickness is app-specific. That means patients can only access
this feature if their provider’s medical system implements it [10]. Therefore, this kind of issues should be resolved to
make the transition smooth. Additionally, there is still need for metrics to measure the efficiency of this technology in
healthcare. Some researchers propose to include metrics such as policy compliance, high-level computation ability,
authentication, interoperability, scalability, cost-effectiveness, and domain-specific healthcare requirements [10, 16].
4.3. Technology
Advantages: The blockchain technology infrastructure is flexible, adaptable, agile, and secure with high performance
and low latency [17]. It offers much for healthcare sector as it does for other sectors. With the help of decentralized
technology, time consuming and resource-intensive authentication and information processes can be avoided which
makes healthcare procedures quicker [13, 14]. Blockchain technology has been in use. Software designed to ensure
the transparency of medicine manufacturing process to track medical distribution, and ensure the authenticity of
prescriptions for compliance with the Drug Supply Chain Security Act [13].
Disadvantages: Cost and complexity can cause negative consequences for healthcare stakeholders. Because of the
high-cost of data centers, many EHR services may migrate to third-party providers, which in turn healthcare providers
may have to pay to access the data [7]. The technical complexity of the cryptography and networking involved can be
difficult to understand for all stakeholders. Many patients might be reluctant to manage their medical records owing
to the complexity of blockchain setup [5]. Another technical disadvantage of blockchain is that it is not ideal for data
with high temporal resolution and also issues with handling multi-dimensional data, such as complex text, images,
and graphs [8]. Moreover, since it is an open network that anyone can join, it needs massive computing power for
effective tamper resistance [8, 17].
Challenges: The cost-effectiveness and efficiency of handling large volumes of data have yet to be tested in
production environments. Once the traffic increases, the transaction time can get long depending on the protocol; thus
impacting the scalability [4] and required computation power. The practicality of expenditures and set up for hardware,
software, implementation, and support need to be assessed while transitioning current electronic health system to
blockchain-based technology [13]. Moreover, a global standard is also needed to store, access and share encrypted
data in the cloud [12]. The last challenge is that until now there is no proof to indefinitely say the data blocks cannot
be spoofed, decrypted, or rearranged, thus questioning the security aspect. Hypothetically, if the whole network is
taken over by the malicious attackers, there is a 51% chance of security threat [4, 7].
5. Research Gaps:
From the systematic analysis of literature review for blockchain in healthcare, evidently, this technology offers many
advantages for healthcare. Being an open-source technology, and its promise in providing high-level security and
transparency during data sharing and financial transactions, the interest in adapting blockchain into electronic
healthcare has been increasing exponentially. However, despite the hype and gaining popularity, we have identified
some principle research gaps that need to be addressed in this field. Firstly, although blockchain technology promises
secure sharing through a distributed network, there is always a possibility that hackers may find a way to break the
security system. A research study says having 51% malicious nodes would make blockchain vulnerable to security
threats. In this context, profound research has to be done on how to combat if such situation was to occur in the real
environment. Secondly, if the blockchain technology were to implement globally across all the health providers,
Alla, Soltanisehat, Tatar, and Keskin
would the intense data traffic could be handled, while still maintaining the speed and scalability? Thirdly, maintaining
high-cost data centers that require vast amount of electricity is another cost related challenge. Patients might not be
ready to share the financial burden, considering the fact that already the medical costs are very high. Fourth, access
management, legal issues, regulatory issues should be made taking all nations’ medical policies into consideration.
Alternatively, the notion of having a unified data storing and sharing system would be far from reality. Training the
stakeholders on the usage of this new complex system would be another grave challenge. There are many more
challenges to address. However, the above mentioned are to be tested indefinitely before investing in this technology.
6. Conclusion
In this paper, we introduced blockchain technology, which is well known for its application in cryptocurrencies but in
fact, has a broader application from finance to healthcare. Research on blockchain has emerged since 2012 intensively.
However, integration of blockchain in healthcare is new and trending area. The blockchain is presented as a paradigm
changer with its innovative approach to decentralized management, robustness, security and immutable audit trail.
Early applications of blockchain in healthcare has shown that it is not only changing technology but also a way of
doing business, redefining the relations of actors from healthcare providers to patients, pharmaceutical industry to
scientists. There are also concerns about blockchain technology, which requires scrutiny. Transparency,
confidentiality, speed, and scalability are mostly technical issues to be addressed. There are also legal and regulatory
issues to be handled. Before redesigning healthcare system with blockchain, feasibility studies, which employ a system
of systems approach, should be done. The system of systems is the key approach for feasibility studies since it
considers all three aspects of people, process, and technology to provide a holistic view.
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