J. Nig. Soc. Phys. Sci. 5 (2023) 992

Journal of the
Nigerian Society

of Physical
Sciences

Secure Health Information System with Blockchain Technology

A. E. Ibora,∗, E. B. Edima, A. A. Ojugob

a Department of Computer Science, University of Calabar, Calabar, Nigeria
bDepartment of Computer Science, Federal University of Petroleum Resources, Effurun, Nigeria

Abstract

This paper focuses on highlighting the problems that are associated with the absence of privacy and security of medical records in a healthcare
system. It seeks to bridge the gap between the currently used security protocols in the management of health information, and encryption
algorithms that should be used. Extant health information systems have always been developed with conventional databases. With all the
privileges to read, write and execute assigned to the administrator, who has centralised control over all medical records, there is the likelihood of
the misuse, distortion and loss of such records in the event that the administrator becomes compromised or inadvertent system failure. To solve
this problem, the use of decentralised and distributed databases becomes paramount. Blockchain technology has recently received much attention
due to its ability to permit a peer-to-peer network with distributed databases that can be stored locally on each node in the network. Subsequently,
all updates on records in a database are communicated to all participating parties, hence addressing the problem of centralised control. In this
paper, we propose a health information system on a blockchain to create a trust-free system for both health personnel and patients. From the
results obtained, we achieved the decentralisation of the medical records’ database to enhance the security and privacy of data on the modeled
peer-to-peer network.

DOI:10.46481/jnsps.2023.992

Keywords: blockchain, health information system, distributed databases, encryption algorithms, medical records

Article History :
Received: 16 August 2022
Received in revised form: 06 November 2022
Accepted for publication: 06 November 2022
Published: 29 April 2023

© 2023 The Author(s). Published by the Nigerian Society of Physical Sciences under the terms of the Creative Commons Attribution 4.0 International license

(https://creativecommons.org/licenses/by/4.0). Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Communicated by: Tolulope Latunde (Ph.D.)

1. Introduction

Computers have been employed in the delivery of health-
care services and their usage has been helpful in enhancing
operational efficiency and clinical services. However, the
current paradigm shift in the healthcare industry brings to light
the challenges of maintaining the integrity of medical records.
With the advancement in information and communication
technology, healthcare delivery has come with new formats and

∗Corresponding author tel. no: +2348154213807
Email address: ayei.ibor@unical.edu.ng (A. E. Ibor )

structures – from evidence-based medicine to e-medicine and
remote e-health services [1]. Similarly, the application and use
of computer-based solutions in healthcare is witnessing new
dimensions, thus, giving room to novel security flaws. These
emerging security flaws require effective defence mechanisms
to contain likely unauthorised access, modification and distor-
tion of medical records.

The World Health Organisation defined a Health Infor-
mation System (HIS) as a system that is able to capture,
store, manage, and transmit health-related information. In this
sense, achieving a functional HIS is paramount in enhancing

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A. E. Ibor et al. / J. Nig. Soc. Phys. Sci. 5 (2023) 992 2

the storage and retrieval of medical records. According to
[2–4], a typical HIS must allow for the effective collection,
processing, reporting, and use of health-related data across
different health-based units. Current approaches to health
information systems rely mostly on centralised databases with
administrative control and policies, as well as authoritative
access. In this case, changes and updates are only effected by
an administrator or super user, and any other person to which
such rights and privileges are assigned. This nontransparent
transaction policy creates room for the possibility to distort
records and compromise the integrity of classified medical data.

In recent times, the emergence of disruptive technologies
such as the blockchain provides the capacity of managing
distributed databases, which can be updated and locally
stored across all nodes in the network. According to [5],
the blockchain is a distributed database of records (or public
ledger) of all transactions, which are executed and shared
among participating parties. Similarly, [6] argued that in a
blockchain, transparency is inherent, thus, permitting that
updates on records are only possible when a majority of
the participants reach a consensus. New insights into the
expansion of HIS show that it has the potentials to increase
the accessibility to medical records [7–9]. However, the use of
conventional and centralised databases limit such possibilities
as authentication credentials are granted from a central point.
In the event of a failure of the database, loss of records becomes
inevitable, in which case, the operations of the target system
will be truncated in real time. These limitations necessitate the
need for a decentralised database that is difficult to compromise
in terms of data integrity, confidentiality and availability.

Current implementations of the blockchain enable the use
of a public ledger, which consists of the information of all the
participants and transactions on the blockchain [6–10]. The
information captured as well as the digital transactions that
have ever been executed on the blockchain can be recorded and
shared across the peer-to-peer blockchain network. Similarly,
[11] asserted that users can validate transactions, and also have
identical copies of these transactions on their local machines.
In this way, health information can be securely stored, updated
and transmitted without unauthorised modification. Further-
more, it is easier to track all updates as the information stored
in the blockchain database is always complete and includes
all records of transactions from the point of origin of the
transactions.

Health information requires a high level of accuracy at all
times as minor changes in such data can lead to very unpleasant
results with a plethora of consequences. With the blockchain
network being able to perform periodic self-updates, it helps
to deliver a self-reviewing system that is computationally
infeasible and expensive to compromise. Transactions stored
cannot be erased without the consensus of all participating
parties. In this sense, it will be feasible to store and track
medical records irrespective of the location of the Health
Maintenance Organisation (HMO), patients, nurses, doctors,

and other health personnel. In addition, patients’ past illnesses,
which are recorded on the blockchain can be useful for the
proper treatment of patients in contrast to systems that run on a
centralised database with limited access and the possibility of
central point of failure.

To address the problem of authoritative access and cen-
tralised control of the database of medical records, this paper
proposes a secure system for managing medical records using
the blockchain technology. The use of the blockchain provides
distributed access to the database of medical records to forestall
the problem of single pint of failure. In the same sense, it be-
comes impossible to modify the stored medical records without
the consensus of the participating parties, thus making the stor-
age and transmission of medical records an entirely transparent
process. To implement the blockchain, we used Python, GO,
Docker Engine, interplanetary file system (IPFS), and other
technologies with significant results obtained from rigorous ex-
perimentation. The rest of the paper is organised as follows; the
review of the related literature is discussed in section 2. In sec-
tion 3, the materials and method are discussed while the results
and discussion are presented in section 4. Finally, the conclu-
sion with future research direction is given in section 5.

2. Review of Related Literature

A detailed analysis of the existing healthcare information
systems is provided in [12]. The authors argued that comput-
erisation is significant in realising an efficient HIS. Similarly,
they investigated the security of medical records and were
able to give the design of a computerised system used by the
National Heath Management Information System (NHMIS).
The implemented system was able to allow the safekeeping of
patients’ records with basic components of running an effective
and productive hospital. This notwithstanding, the system ran
on a local server database that served as the repository for all
medical data including queries and reports.

In [4], the evolution of HIS is highlighted. Areas of interest
include the migration from paper-based to computer-based pro-
cessing and storage, the availability of global and regional HIS,
the use of health-related data for effective healthcare planning,
and the deployment of technology for health monitoring. These
aspects of HISs have witnessed tremendous improvements
alongside an increase in health-related data. It is therefore
pertinent to have a robust mechanism through which the
escalating amount of medical records can be effectively stored,
queried, reported and transmitted. Furthermore, [3] highlighted
the design and implementation of a HIS, and discussed the
possibilities of improving its structure through the use of a
comprehensive, integrated and decentralised system.

Similarly, [13] assert that the tendency to manually rec-
oncile medical data among clinics, hospitals, laboratories,
pharmacies and insurance companies has not been a successful
process. This is due to the fact that no single list of the
disparate locations housing patients’ data exists, and at the

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same time, it is difficult to ascertain the order of data entry
to determine the records, which predate the others. In other
words, determining the medications a patient is actually taking
using antecedents of prescriptions may be unclear. In the same
sense, every electronic health record uses different workflows
to store data so that it becomes unclear who recorded what and
when.

In [14], MedRec is proposed. MedRec is a decentralised
record management systems using blockchain technology. The
proposed system is able to give patients a log of their com-
prehensive, accessible and credible medical history. MedRec
allows participants to be informed of their medical history
including any form of modifications on these records.

It is argued in [15] that the use of blockchain can be
helpful to tackle the lagging in HIS, which runs on local server
databases. This is a fact as patients whose medical records
are managed by HIS running on a local server database have
limited privileges to such data. Consequently, the administrator
may alter these records or deny patients access to same.

There are several attempts by malicious users to com-
promise the security of medical records. Cyberattacks such
as SQL injection [16], which targets the data aggregated on
the database over time are very common. To this effect, the
use of various disruptive technologies such as the blockchain,
artificial intelligence, and internet of things for protecting
medical records from human errors and cyberattacks is
discussed in [17]. The different application areas of these
technologies were also highlighted in this work including their
security-related concerns. Specifically, the authors identified
the use of blockchain-based trust models in the implementation
of data management in the healthcare sector to optimise the
process flow and reduce the operational costs.

The authors in [18] argued that the blockchain facilitates
the use of a decentralised and distributed environment devoid
of a central authority. Since the transactions on a blockchain
are both secure and trustworthy, its use in healthcare for
realising patient-centric approach to healthcare systems and
maintaining accurate electronic healthcare records is cru-
cial. From their findings, the authors agreed that the use of
blockchain technology in healthcare allows for the sharing of
data, the accurate management of health records, and access
control. In the same sense, the use of lightweight blockchain
architecture for the management of healthcare data is proposed
in [19]. The approach is able to reduce the computational and
communication overhead of Bitcoin network using clusters,
where each copy of the ledger is maintained per cluster.
Each cluster consists of network participants that are able
to use canal for secure and confidential transactions. Their
approach was also targeted at eliminating the problems of
traditional client-server and cloud-based systems deployed in
managing healthcare data. Some of these problems include
single point of failure, centralised data control, inherent system
vulnerabilities, and data privacy.

Consequently, the benefits of using blockchain for health-
care are highlighted in [20]. Some of these include distributed
ledger, decentralised storage, authentication, security and
immutability. The authors posited that the application of
blockchain in healthcare improves data sharing capabilities,
integrity, availability and authentication. In other words, the
blockchain will allow patients to have control and ownership
of the sharing of their medical data in a secure environment.
Besides, [21] identified electronic health records and personal
health records as the most targeted areas that rely on blockchain
technology. They claimed that access control, interoperability,
and data integrity are issues that the use of the blockchain in
healthcare has helped to improve.

One significant feature of the blockchain remains that it
cannot be easily compromised [22]. When a block is cre-
ated, a one-time hash is generated. This hash is unique to the
blockchain and is generated using the values of the features of
each block. Changes to values in the block invalidate the hash
as well as the block making the blockchain unbreakable as il-
lustrated in Figure 1.

Figure 1: An Illustration of the Blockchain

As shown in Figure 1, putting information in the blockchain
creates a block that contains the present and previous hashes.
The first block is known as the genesis block, and has the
present hash and previous hash. The second block is then
created and the hash of this block is linked with the genesis
block, and so on.

In this sense, [15] asserted that the use of blockchain inno-
vation allows a verified HIS to resolve certain issues, for ex-
ample, moderate access to medical information, framework in-
teroperability, improved quality of medical data, and trust-free
transactions. In addition, the significant advantages of the usage
of blockchain in the security of medical records are highlighted
in [13, 22–25]. These include:

i. Distributed Database: Each patient on a blockchain can
access the entire database from its origin and be able to confirm
the records of his/her information or data straightforwardly,
without a middle person.

ii. Peer-to-Peer Transmission: Communication happens le-
gitimately between nodes rather than through a focal hub. Ev-
ery node stores and advances data to every other node.

iii. Transparency with Pseudonymity: Every transaction
and its related components are obvious to anybody with access

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to the blockchain. Every node, or client, on the blockchain has
a unique identifier of 30 or more alphanumeric code that dis-
tinguishes it. Clients can stay unknown or give confirmation of
their identities to other people. All transactions happen between
blockchain addresses.

iv. Irreversibility of Records: Once a transaction is entered
in the database and the records are refreshed, the records
cannot be adjusted, in light of the fact that they are connected
to each record that preceded them (subsequently the expression
”chain”). Different computational algorithms and methodolo-
gies are used to guarantee that the chronicle on the database is
lasting, sequentially ordered, and accessible to all others on the
system.

Other advantages of using blockchain technology include
the use of smart contracts for computational logic, scalability,
and the infeasibility of a single user compromising the entire
blockchain [26–30]. From the literature, the inherent problems
of centralised and authoritative databases can be addressed by
the use of the blockchain. Some of these problems include:

i. Standalone System: This requires authoritative access
and mostly not suitable for large scale networks.

ii. Cloud based Systems: It may be cheap to implement but
may not have the appropriate mechanism for allowing se-
cured transparent transactions. It can also lead to data
loss and theft in the event of espionage or system failure.

Therefore, it is envisaged that the use of blockchain will
help to resolve the highlighted issues since it is a peer-to-peer
network where each participant has the database stored locally
in each of the nodes in the blockchain network. Changes to
stored records are transparent to all participants and no partic-
ipant can authoritatively make a change without the consent of
others.

3. Materials and Method

In this section, the design of the proposed system is dis-
cussed. The design highlights details of the functionality of the
system in terms of data storage, transmission, access and re-
trieval for all relevant parties.

3.1. Method

The blockchain is developed by creating a secure and
transparent environment for medical records. Using a 3-tier
architecture, the blockchain serves as the underlying database
for the storage and authentication of medical records. The
client side of the 3-tier ensures the transmission of data to
the blockchain’s network. These data is processed at the
logic layer, which interfaces with the blockchain to determine
the integrity or otherwise of the medical record using the
hash code of each block. These hash codes are used to keep
the medical records safe in the blockchain. The hash codes
are generated by mapping a variable length input such as
a patient record to a fixed length output. This fixed length
output is the hash value of the record, and will change when

the block of information holding the medical record is changed.

The blockchain network is a decentralised structure with
peer-to-peer nodes. These nodes inspect and authenticate the
validity of any new transaction such as a storage or retrieval re-
quest. This request is then fulfilled though distributed consen-
sus by different validating nodes. Moreover, no single validat-
ing node can have centralised control of the blockchain, making
it difficult for medical records to be corrupted, distorted, stolen
or compromised. The architecture of the proposed system is
shown in Figure 2.

Figure 2: Architecture of a Secured HIS with blockchain technology

In the 3-tier architecture as shown in Figure 2, there is a
client side, application server and the blockchain database, in
which the server-side procedures, data memory access, data
storage and user interface (UI) are created and kept up as
autonomous modules on isolated stages.

The 3-tier design permits any of the three layers to be re-
designed or supplanted freely. The UI is actualised on a work-
station and utilises a standard graphical user interface with vari-
ous modules running on the application server. The three layers
in the 3-tier architecture are as follows:

i. Client Side: This is the first tier and shows data identified
with services accessible on the desktop application. This
layer speaks with different layers by sending results to
the peer-to-peer network and different layers in the sys-
tem. It is a platform that enables the client to interact
with the system. The client side was built on Hyper-
text Markup Language (HTML), Cascading Style Sheet
(CSS) and JavaScript.

ii. Application Server: This is the second, which is addi-
tionally called the business logic or logic layer. This
layer controls application usefulness by performing com-
prehensive processing. This layer was built on node.js,
composer, and Docker engine.

iii. Blockchain Database: This is the last tier of the architec-
ture. This layer houses the database servers where data

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is stored and recovered. Information in this tier is kept
free of application servers or business logic. This layer
was built on ganache, yarn and truffle (Ethereum Hyper-
ledger Smart Contracts).

3.2. Activity Diagram
An activity diagram represents a series of actions or flow of

control in a system similar to flowchart or a data flow diagram
[31]. The activities modeled can be sequential and concurrent.
Figure 3 shows the activities performed by each entity/class of
the system and these activities are discussed thus:

i. The health personnel and patient attempt to login by
entering their respective usernames and passwords, and
await authorisation from the blockchain database. If the
username and password is invalid it aborts the operation
but if valid the users (health personnel and patient) gains
access into the system and are assigned individual privi-
leges.

ii. The health personnel views patients’ medical history, di-
agnose, run tests on the patient and then upload the med-
ical results into the system. The blockchain encrypts the
medical result and shares to multiple participants in the
network for consensus.

iii. The patient views the medical result uploaded by the
heath personnel and can request for modification in bio-
data. The request is sent to the blockchain database and
propagated across the network for subsequent approval
or decline of the request. If the request is approved the
changes are effected otherwise the operation is aborted.
One participant cannot make changes without the cosen-
sus of other participants in the network, otherwise the
data is said to be compromised.

4. Experimental Results and Discussion

An implementation of the architecture of the proposed sys-
tems is given in this section. Several experiments were con-
ducted to test the developed application for realising distributed
access to medical data based on the design of Figures 2 and 3.
The application used is built using existing technologies such
as node.js, truffle smart contract, inter-planetary.

4.1. Testbed of the Experiments
The proposed system was implemented on a Windows ma-

chine running Windows 10 64-bit operating system, x64-based
processor with 4GB RAM and Intel ® Core i3 6100U CPU
@2.30 GHz 2.30GHz.

4.2. Software Components
An implementation of the architecture of the proposed sys-

tems is given in this section. The software used is built us-
ing existing technologies such as node.js, truffle smart contract,
inter-planetary file system, Docker engine. With the implemen-
tation of the blockchain, medical records were cryptographi-
cally stored on a peer to peer network. The components used in
building the software are as follows:

i. HTML: is the standard markup language for creating web
pages. It describes the structure and elements of a web
page.

ii. CSS: It is a style sheet language used for describing the
presentation of a document written in a markup language
like HTML.

iii. JavaScript: JavaScript, often abbreviated as JS, is a high-
level, interpreted programming language that conforms
to the ECMAScript specification.

iv. Python: Python is an interpreted, high-level, general-
purpose programming language. Python has a design
philosophy that emphasises code readability, notably us-
ing significant whitespace. It provides constructs that en-
able clear programming on both small and large scales.

v. GO: Go is a statically typed, compiled programming lan-
guage that is syntactically similar to C, but with memory
safety, garbage collection, structural typing, and CSP-
style concurrency.

vi. Yarn (extension yarn.lock): In order to get consistent in-
stalls across machines, Yarn needs more information than
the dependencies you configure in your package.json .
Yarn needs to store exactly which versions of each de-
pendency were installed. To do this Yarn uses a yarn.lock
file in the root of your project.

vii. Docker Engine: It is the underlying client-server technol-
ogy that builds and runs containers using Docker’s com-
ponents and services. Docker Engine supports the tasks
and workflows involved to build, ship and run container-
based applications.

viii. Electron.js: Formerly known as Atom Shell is an open-
source framework developed and maintained by GitHub.
Electron allows for the development of desktop GUI ap-
plications using front and back end components origi-
nally developed for web applications: Node.js runtime
for the backend and Chromium for the frontend. Electron
is the main GUI framework behind several notable open-
source projects including Atom, Visual Studio Code, and
Light Table.

ix. InterPlanetary File System (IPFS): InterPlanetary File
System (IPFS) is a protocol and network designed to cre-
ate a content-addressable, peer-to-peer method of stor-
ing and sharing hypermedia in a distributed file system.
IPFS is a peer-to-peer distributed file system that seeks
to connect all computing devices with the same sys-
tem of files. IPFS could be seen as a single BitTorrent
swarm, exchanging objects within one Git repository. In
other words, IPFS provides a high-throughput, content-
addressed block storage model, with content-addressed
hyperlinks.

4.3. Results and Discussion

This section discusses the results of the experiments
conducted to validate the efficacy of the proposed system.
At the initial stage, a folder is created and populated with
any category of health records either for the health personnel

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Figure 3: The Activity Diagram of the Proposed System

Figure 4: Encrypted Folder of Health Personnel

Figure 5: Encrypted Patient’s Folder

(doctor, nurse etc.) or the patient. This folder is then encrypted,
for which a hash value is generated. The generated hash value
as shown in Figure 4 can be used to perform such operations
as the copying and sharing of the folder across the peer-to-peer
network. Both the health personnel such as the doctors and the
nurses, and the patients can participate in the viewing of the

Figure 6: Adding File to the Encrypted Folders

Figure 7: Importing Files with Hash Value

shared folder. The folder at the same time can be opened in a
browser to view the records stored in it including the ability to
download it to a local machine.

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Figure 8: Activities on the Blockchain

Similarly, a patient’s folder undergoes the same process as
shown in Figure 5.

In the next stage, files are added to the created and en-
crypted folders for each entity participating in the blockchain.
The added files are encrypted and hash values assigned to
them to protect the integrity of their contents. This process is
depicted in Figure 6.

Files can then be imported across the network and stored
locally using the hash value earlier created for each file as
illustrated in Figure 7. In this way, health personnel and
patients have access to the health records transparently, and
modifications to files are flagged when the hash values change.

All transactions (activities) in the blockchain by the differ-
ent participating parties as well as the processes on data are
also transparent and available to all nodes in the blockchain.
Sample transactions are depicted in Figure 8.

Furthermore, we can view the total amount of data stored
by multiple nodes participating in the network as well as
the number of nodes connected to the blockchain per unit
time. This number increases as more nodes participate in
the blockchain (see Figure 9). In this sense, it is possible
to maintain a transparent and distributed database of health
records, which are cryptographically secure and immutable
over time.

Figure 9: Used space and Peers Connected to the Blockchain network

5. Conclusion

The proposed system runs on a peer-to-peer network to
eradicate the actions of a middle man or administrator. Inter-
action between the patient and health personnel, including hav-
ing access to medical records shapes a crucial piece of the fo-
cal activities underlying health information systems. The pro-
posed system was able to achieve the decentralisation of the
medical records database to enhance the security and privacy
of data on the modeled peer-to-peer network. The encryp-
tion of patients’ data across the IPFS and the relevance of a
public/private key pair to share, upload and download data on
the blockchain network had an added advantage of the secu-
rity and privacy of medical records. The proposed system was
designed to aid health management organisations in the stor-
age and retrieval of medical records. The system is modeled
to tackle problems arising from data integrity, data security and
the manipulations of medical records, which have been the ma-
jor challenges in extant health information systems. Since the

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blockchain is a public ledger that provides the information of
all the participants and all digital transactions that have ever
been executed, it helps to negate the relevance of authoritative
access to a database of medical data. In this sense, the proposed
system will bring about an accurate and efficient way of trans-
ferring medical records from health personnel to the patients
without instances of record manipulation. For future work, we
intend to provide a large scale implementation of this work on
a district-wide basis to ascertain its resilience in real time.

Acknowledgment

The authors appreciate the handling editor and the reviewers
for their valuable comments that improved the quality of this
paper.

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