Blockchain & Healthcare

BlockchainLab 19 Apr 2018,

Introduction to Blockchain

Blockchain is a distributed protocol that allows to exchange information or value (tokens), between two or more parties. The information in form of transactions contained in the network is validated through consensus. Blockchain network acts as a source of trust between parties. Namely, it is a protocol that generates trust in a distributed system. A Blockchain system or application is a software that implements this protocol, whereas a Blockchain network is formed by parties executing that software in their computers.

Currently, most of the value exchange networks are centralized, in the sense that they depend on a central point or authority that certificates the validity of the transactions. Central certification does not guarantee unicity nor authenticity of information. Using Blockchain, validation works under distributed principles: value transactions are directly performed peer to peer, as the roles of the participants is transformed. That way, availability is increased, and doors open for new business models of collaborative economy. Blockchain technology assumes the role of a trusted third party (TTP), validating transactions.

The protocol establishes that each network participant stores the valid data under a certain structure, also called Blockchain or Chain of Blocks (ergo, the name of the technology). The rules of the protocol and the chain of blocks design make the data structure an immutable register of peer to peer transactions. A block is nothing more than a group of transactions registered in the network, whereas the chain is a list of blocks cryptographically linked. That link gives immutability to the chain because it makes it practically impossible to modify any link of the chain.

Blockchain technology has 3 main features that add value to any use case it is applied to:

  1. Data integrity: as the Blockchain is immutable, data integrity is guaranteed. For this reason (and because the chain stores transactions), Blockchain can be considered as an unforgeable distributed ledger.
  2. Consistency: all the network nodes have the same version of data, once added to the Blockchain.
  3. Fault tolerance: information is replicated over the nodes, reason why it will be available even in the event of failure of one or several network member nodes.

It is important to highlight that there are private and public Blockchain networks. Public Blockchains, as Bitcoin, can be accessed by any person, whereas private ones are accessed by closed groups of authorized participants.

Smart Contracts

Blockchain’s potential is greater than distributed ledgers, because it can solve many other types of trust problems between peers. We simply need to define the information to be saved in the Blockchain, namely the data to be validated and shared and subsequently, stablish the rules the data must comply with.

Smart Contracts are used to set the specific rules applied to the assets represented in a Blockchain network. A Smart Contract is a software program executed in a Blockchain and created by one of its users. Normally their objective is to manage digital assets, reflecting the existing agreements between network users.

Therefore, this type of contracts can automate transactions that meet specific business logic and rules. In fact, large complex companies have been already implemented in Blockchain platforms, like the DAO (Decentralized Autonomous Organization), expressing its whole business logic into Smart Contracts hosted in the Ethereum network.

Any transaction made between these software programs is registered in the Blockchain, and all the users can verify the validity of the information transmitted.

The three main features of Smart Contracts are the following:

  • Neutrality: A Smart Contract contains rules and conditions that users previously agree on. The contract cannot be subsequently manipulated because it is saved in the Blockchain.
  • Atomicity: The execution of a Smart Contract is always consistent. If an error occurs during execution, any change is automatically rolled back.
  • Transparency: As the Smart Contracts are embedded in Blockchain, all the members of the network have a copy of the contract’s code and can verify compliance and validity of the rules programmed.

Blockchain in the current context

Blockchain technology has created a great global hype in the business and academic fields. Signs of this interest can be found in the huge number of proofs of concept and productive applications created in many sectors and countries.

The financial sector has clearly been the most active. Globally speaking, several consortiums have been created, among which R3 is the most important, formed by more than 80 financial multinational companies, having invested more than 100 million dollars in the project. In Spain, the most important consortium is leaded by Cecabank and Grant Thornton, and it represents 33% of the Spanish financial system. The effort at Cecabank is constantly driven towards developing new use cases for the financial sector. One of the biggest multisectoral consortiums, Alastria, was also created in Spain.

On the other hand, the public sector has brought up projects like Catena prototype, from Canada’s Government, where the public investments in private companies are registered. Additionally, United Kingdom has bet for incorporating blockchain as one of the services offered within the frame of G-Cloud 8, digital marketplace where public sector organizations acquire cloud services.

In this sense, public sector is also investigating future Blockchain applications such as digital voting systems, digital identity management, ownership titles, official document timestamping, etc.

The European Union is also involved in the research and development of this technology. Among all the existing initiatives, Project Decode, as part of the H2020 program, can be highlighted. It is participated by Spanish universities and is backed by a 5 million euro fund, to implement digital identity using Blockchain. As part of the FP7 and H2020 programs, it is estimated that for 2020 340 million euro will have been invested for the investigation of Blockchain. Also, on the 1st of February of 2018, the European Commission created the “Forum and Observatory of Blockchain in the UE”, to promote this technology and inform about its news and breakthroughs.

In the energy sector, between Spanish companies Gas Natural and Endesa, the first energy market operation was closed using Blockchain, where a volume of 5,95 GWh of natural gas was traded.

The impact of Blockchain is not limited to the previous areas. Other potential cases can be found in predictive markets, diamond traceability, art piece property fragmentation, academic record management or creating trust and traceability in engineering projects.

Blockchain in the health sector

Health sector can witness substantial improvements thanks to Blockchain’s potential. Several studies and polls reveal that the interest in Blockchain has considerably increased and it is estimated that a high number of applications will be in production by the end of 2018. There are many use cases:

Medicine and IoT

Internet of Things (IoT) can considerably improve current health systems. Devices as electronic bracelets, heart pacemakers, blood sugar sensors, etc., create clinical information from patients in real time, providing more precise and updated data about their health. In this scenario, it is crucial to guarantee the security and correct transport of the information generated. Blockchain systems can work as information exchange platforms over which medical devices transmit patients’ health data. Thanks to the features of this technology, digital identity of the patients can be secured, and their data exchanged and stored safely and with total integrity.

Fighting against forged pharmaceutical drugs

Forged pharmaceutical drugs are those whose components lack the active ingredients or that do not have the correct proportion of them. They could potentially cause great harm to patients. To prevent the distribution of forged pharmaceutical drugs, their authenticity and legitimacy of their origin is tracked and traced along the supply chain, from manufacturing to dispensing. This method is also known as “pharmaceutical serialization”.

Thanks to Blockchain technology, we can create a shared register for all the participants in the supply chain in which lifecycle of the pharmaceuticals and their components can be tracked and traced. This register could be global, allowing users and providers to electronically verify that the lifecycle of the drug is legitimate, easily checking its authenticity.

Grant Thornton’s use case: Interoperability of medical records

Electronic Medical Records (EMR) are the most important type of asset in any software application manufactured for the health sector. Nevertheless, in the current technological environment, there is no standardized infrastructure allowing the different health providers to exchange patient information. E.g., a public hospital cannot share medical records with a private one. Consequently, the medical record used by doctors is usually incomplete, because it does not contain data from other providers. This can lead to inefficient medical attention and ultimately entail severe risk for the patient’s health. Additionally, patients cannot easily control the access to their medical record, neither decide to share it between public and private health providers.

To tackle with this problem, Grant Thornton has investigated a proof of concept consisting in a Blockchain based distributed application. The objective is to improve patients’ medical information management, giving patients the right to decide who can access their data, securing information’s integrity, privacy and consistency. Additionally, data can be easily shared between medical institutions, thanks to the system, that works as a common data exchange platform.

In this application, the Blockchain stores data of the medical records’ status allowing to check their integrity. Additionally, the chain stores meta data that indicates the access permissions granted by patients to providers. These permissions are granted and revoked thanks to Smart Contracts embedded in the Blockchain.

When a person attends a medical appointment, the doctor requires the last version of the patient’s electronic medical record. The application verifies that the doctor’s medical institution or hospital has been authorized by the patient to access his medical record. After this verification and in case access it is granted, the doctor downloads the medical record from another authorized provider’s database. When the medical record is downloaded, the integrity of the meta-data stored in Blockchain is verified.

Once the patient has been attended, the doctor updates the medical record and a new transaction is triggered in the Blockchain, indicating the record’s new status. Additionally, the rest of the authorized providers is notified about the transaction, and therefore the last version of the medical record can be downloaded in their systems.

The benefits are considerable:

  • As there is only one unique version of each medical record, updated by the different medical specialists and institutions involved, a more precise medical attention can be offered to customers, improving their quality of life and, potentially creating a competitive advantage.
  • Blockchain can work as a mechanism to guarantee provider’s compliance with the different data protection regulations (GDPR, etc.), as it registers all the permissions granted by the patients and tracks the use of the medical records.
  • Patients transferred from public health institutions to private hospitals could transfer their medical records electronically, in a simple an automatic way. This process makes this data sharing more agile, improving medical attention quality.
  • As this application stores medical data in a consistent, precise and updated database, it could be the foundation of different services aimed to improve medical attention, such as the use of Artificial Intelligence (AI) to predict future diseases of patients by studying his medical records, paying cryptocurrencies to anonymous people that provide information for the investigation of diseases, among many others.

As it has been explained, Blockchain promises to become the driving force of a new technological revolution for the value exchange paradigm. Thanks to the immutability, fault tolerance and transparency of Blockchain, it can remove the need of trusted third parties taking care of the security of transactions, democratize control of information and connect in a transparent and secure way exchange networks or isolated databases, giving birth to a new age of information management and opening the door to endless possibilities.


This article was first published in number 128 of I+S journal, from Healthcare Computer Spanish Society (SEIS, in spanish), in April 2018.

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