## 2 Literature Review
### The Role of Blockchain Technology in Healthcare Services
\begin{table}
\begin{tabular}{c c c c c c} \hline
**Ref.** & **Usage Field** & **Technologies** & **Data** & **Stakeholders** & **Contribution** \\ \hline
[19] & EHR Management & \begin{tabular}{c} Blockchain-based on \\ Hyperledger Fabric and PBFT \\ algorithm \\ \end{tabular} & \begin{tabular}{c} Data on cognitive behavioral \\ therapy for insomnia (CBI) \\ \end{tabular} & \
\begin{tabular}{c} Patients, therapists, \\ and mobile application \\ providers \\ \end{tabular} &
\begin{tabular}{c} Data collected via mobile devices \\ has been securely stored in a decentralized manner. \\ \end{tabular} \\ \hline
[20] & EHR Management & \begin{tabular}{c} Ethereum-based blockchain and \\ Smart Contracts \\ \end{tabular} & \begin{tabular}{c} Patient diagnosis information, \\ medical history, and data related \\ to treatment processes \\ \end{tabular} & \
\begin{tabular}{c} Patients, healthcare \\ providers, and \\ third parties \\ \end{tabular} &
\begin{tabular}{c} A model has been proposed to \\ enhance data inturability and \\ patient privacy. \\ \end{tabular} \\ \hline
[21] & \begin{tabular}{c} Health Information \\ Transfer and Management \\ \end{tabular} & \begin{tabular}{c} Hyperledger-based blockchain \\ with off-chain data storage \\ \end{tabular} & \begin{tabular}{c} Patient diagnosis information, \\ medical history, and data related \\ to treatment processes \\ \end{tabular} & \
\begin{tabular}{c} Patient, caregiver, \\ health practitioner \\ \end{tabular} &
\begin{tabular}{c} The off-chain data storage \\ method has reduced transaction \\ costs on the blockchain. \\ \end{tabular} \\ \hline
[22] & \begin{tabular}{c} Health Information \\ Transfer and Management \\ \end{tabular} & \begin{tabular}{c} Ethereum-based blockchain, QR \\ codes, smart contracts \\ \end{tabular} & \begin{tabular}{c} Patient history, diagnoses, and \\ treatment plans \\ \end{tabular} & \
\begin{tabular}{c} Patient, doctor \\ Patient, doctor \\ \end{tabular} &
\begin{tabular}{c} Integration of blockchain and QR \\ code for enabling patients to gain \\ full control over their health data. \\ \end{tabular} \\ \hline
[23] & \begin{tabular}{c} Pharmaceutical Supply \\ Chain and \\ Anti-Counterfeiting \\ \end{tabular} & \begin{tabular}{c} Hyperledger Fabric-based \\ blockchain, Hyperledger Caliper \\ \end{tabular} & \begin{tabular}{c} Pharmaceutical production \\ information, shipment data, \\ delivery reports \\ \end{tabular} & \
\begin{tabular}{c} Doctor, patient, nurse, \\ pharmacist \\ \end{tabular} &
\begin{tabular}{c} An innovative model has been \\ developed to enhance the \\ traceability of pharmaceuticals \\ and detect counterfield drugs. \\ \end{tabular} \\ \hline
[24] & EHR Management & \begin{tabular}{c} Ethereum-based blockchain, IoT \\ sensors, AL, health digital twins \\ \end{tabular} & \begin{tabular}{c} Glucose levels, blood pressure \\ measurements, biometric \\ health data \\ \end{tabular} & \
\begin{tabular}{c} Patients, healthcare \\ providers, and research \\ institutions \\ \end{tabular} &
\begin{tabular}{c} Real-time health monitoring has \\ been achieved by integrating AI \\ and blockchain technologies. \\ \end{tabular} \\ \hline
[25] & EHR Management & \begin{tabular}{c} Ethereum-based blockchain, \\ smart contracts, machine \\ learning, IoT \\ \end{tabular} & \begin{tabular}{c} Blood sugar and blood pressure \\ measurements; records \\ associated with patients, doctors, \\ and hospitals \\ \end{tabular} & \
\begin{tabular}{c} Patient, doctor, \\ hospitals \\ \end{tabular} &
\begin{tabular}{c} A novel five-layer model \\ integrating IoT, blockchain, and \\ machine learning has been \\ developed for remote monitoring \\ of diabetes patients. \\ \end{tabular} \\ \hline
[26] & \begin{tabular}{c} EHR Management \\ \end{tabular} & \begin{tabular}{c} IoMT devices, Ethereum-based \\ blockchain, Proof of Work, \\ Kecak algorithm \\ \end{tabular} & \begin{tabular}{c} Blood pressure, oxygen \\ concentration, \\ electroencephalogra, \\ measurements, medical imaging \\ \end{tabular} & \
\begin{tabular}{c} Patient, doctor, \\ Pharmacast, insurance \\ companies \\ \end{tabular} &
\begin{tabular}{c} An energy-efficient and reliable \\ health monitoring system \\ integrated with IoMT devices has \\ been developed. \\ \end{tabular} \\ \hline \end{tabular}
\end{table}