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Welcome to the Grapevineworld repository. This repository is about the Grapevine Orchestration Engine (GOE). If you are looking for the other components (the Grapevine APP, the User Dashboard, and the Vendor Façade, please visit the main Github page.

Introduction

Grapevine World is a decentralized, borderless ecosystem for the seamless, standardized exchange of healthcare data. At the core of the healthcare exchange there is the Integrating the Healthcare Enterprise, IHE model, which consists on a set of free and open standards where anyone can contribute. IHE selects technologies following a well-defined methodology based on a set of architectural approaches which are compatible with the well known TOGAF and the European Interoperability Framework, EIF.

Interoperability is a crucial aspect of IT Security and Patient Safety. The ISO 27000 family of standards has three building blocks to identify security measures: the CIA triad, Confidentiality, Integrity, and Availability. If a patient is having emergency treatment and the doctor need to access her Electronic Health Record (EHR), if such EHR is not encoded and transmitted in a format which the First Aid department is able to evaluate due to a lack of interoperability, the EHR is not available thus not secure according to the CIA triad. Often confusion arises amongst the effect named "Vendor Lock-In". In the early stage of the EIF, Interoperability has been foreseen by creating technologically disconnected islands following a specific standard (e.g., HL7) or a specific Vendor. The Free Software Foundation debated this point and welcomed a new revision of the EU strategy, while stressing the idea of openness of solutions, technical specifications, and implementations is a prerequisite not only for interoperability but is crucial for the idea of technoligical neutrality, user-centricity, and reusability. In this regards we believe that the IHE process dramaticaly helps the vision of both the regulators and the free software community to achieve the common goal of secure and interoperable healthcare exchange.

Grapevine World aims at exploiting the IHE process to reach global interoperability. It builds its root on existing initiatives such as:

  • epSOS the first large scale pilot (connecting almost all the EU member states) that provided the first interoperability specifications based on IHE for Patient Summary and e-Prescriptions cross-border exchange
  • e-SENS cross-vertical pilot project that used the IHE process to further enhance and secure the cross-border healthcare exchange
  • eHealth Digital Service Infrastructure the body of the EU commission which is operating under the "New EIF" the Cross-Border e-Health Information Services (CBeHIS)
  • The Trillium Bridge the EU-US initiative for the trans-Atlantic healthcare exchange
  • NwHIN the backbone of the interoperability in the United States of America

The Grapevine backbone interconnects all the healthcare enterprises by using IHE standards (and providing a SDK for those who are not yet using IHE) enabling a healthcare data exchange at a global scale. It is worth noticing that IHE is not limited to the projects above, but it is available worldwide (see the IHE Worldwide page), thus the technology and the standards are available and active all over the world. The above initiatives are the ones in which the Grapevine World team actively participated and contributed.

The GOE

The Grapevine World initiative exploits the Blockchain technology as a facilitating infrastrcuture for the data exchange network, and in providing incentives to participate in the network. At the core of the Grapevine World interoperability we have the orchestration engine. Following the Reactive Manifesto, the GOE ecosystem is shown in the following picture (Source: the Grapevine World Token whitepaper).

The GVW ecosystem

Each patient has data to share, of two kind: clinical and fitness. Electronic Health Records, patient summaries, ePrescriptions, they all fall in the clinical category, while vital signs, lifestyle, sport activities, etc, fall in the fitness category.

Initial foreseen stakeholders of the health data are Charities and NGOs, Teaching institutes, Insurance companies, Pharmaceutical companies, Service providers, application developers (who can access to a set of evolving patient test data) and analytics providers who can in turn offer their services.

Handling clinical data

Clinical data is usually stored in the datacenters of healthcare providers (HCP) or healthcare organizations (HPO) in either proprietary format (Electronic Medical Record, EMR), or ready to be shared (EHR), or even in paper-format. EMRs are system-internal representation of clinical data, and they are not usually interoperable. When a record needs to cross the border of a Healthcare Information System (HIS) becomes an EHR and typical formats are Clinical Document Architecture (CDA, or FHIR Resources). Depending on the granularity of the semantics chosen to represent the data, clinical documents vary from scanned documents, to normal text in prosa (CDA L1), or fully coded in a vocabulary/ontology (CDA L2, L3). Such data flows following such IHE standards as XDS, or XCA, or FHIR across the boundaries of the organizations. The access to clinical data is made using those IHE transactions seamlessly entering in the domain of the hospital and keeping and enhancing the existing security procedures. For those HCPs and HPOs who do not have yet a IHE-based infrastructure, the Grapevine World Façade will perform the EMR-to-EHR translation. The façade has its roots in the national connector of the National Contact Point for eHealth (NCPeH) , the SDK based on Web-Service and RESTFul APIs that connects clinics and hospitals across the European Union. For more information see the Façade repo.

Handling fitness data

Wereable devices, Body Area Networks, and IoT components defines data streams that the patient could potentially share with research institutes, pharmaceutical companies, or insurance companies (in those countries where this aspect is legal). Those devices connect themselves using major frameworks such, e.g., HealthKit. By leveraging those frameworks, patient could allow those fitness data streams into the GOE using the Grapevine World App and make them available for further analysis by the various stakeholders.

Privacy

Notably, clinical and fitness data fall in two different security and legal context. A pillar of the GOE is that nor clinical nor fitness data is stored, and the data processing is completely anonymous. The GOE goal is only to connect various stakeholders by effectively and securely sharing the data streams, while collecting payment and rewards in Grapes and distributing across the various actors. We try to make the user completely unlinked to his data. For more information on user handling and registration, please see the User Dashboard repo.

Overarching architecture

The architecture of the Grapevine World is shown in the next picture. The GVW GOE

In relations to the patterns highlighted in Software Architecture in Practice, in the P of EAA, and in the EIP, we employ a SOA architectural pattern, with a PubSub system. The data broker is is composed by:

  • The GOE, that handles the back-end mechanics of the system. That is when a request arrive at the Data Broker, the GOE is employed to execute the orchestration workflow
  • The Grapevine APP, the primary way patients interact with the data broker
  • The portals, User Dashboard and the HPO Dashboard. The former shares the same functionalities as the Grapevine App, the latter is how HPOs interact with the Grapevine Data Broker

The GOE implements orchestrations following the Actor Model. As each component of the system may fail at anytime, we always try to recover the status of the application using the Event Sourcing pattern. In fact, given the asynchronous behavior of the Ethereum blockchain (interaction with Web3j), and having potential failures from both the HPOs and the App, we aim at implementing the GOE as a set of actors handling Kafka streams, integrated with Akka. A sketch of the Actors would be as per the following tree.

A sketch of the actors

A manager would be assigned to each of the domains in which the GOE interacts (requests from pharmaceutical companies, HPOs, applications, dashboards, etc). Then a set of actors are created on request to evaluate the logic behind each request.

By using such model we allow to have a resilient system which should resist to traffic peaks, totally asynchronous. When a actor fails, thanks to the Event Sourcing pattern, it is restored to its state before the failure by loading all the events.

However the architectural details are yet TBD. The target language is Java.

A Typical use case

Before looking in the details of the possible events, let recap the typical use case shown in Section 6 of the Grapevine World white paper. In this case, a Pharmaceutical company requires data for a trial, and uses the Grapevine Backbone to request it.

Diagram UML of the use case

The case starts ideally with a Patient downloading the Grapevine App. After opening the App, it registers in the GOE (Step 1). The registration involves only sending the Ethereum address and a password (and other authentication factors) for which the patient wants to receive grapes obtained from the enrollement in the Grapevineworld system. Notably, the GOE assigns an UUID to the user, so the Ethereum address may change at anytime. The GOE maintains a tuple <patUUID, eth_address1, ..., eth_addressn> for ethereum addresses used in the current live data requests. Obviously, the patient can (and it is encouraged) to remove addresses when not used. The patient selects HPOs for which it has data, if available. If HPOs are not available in the dropdown list, the patient encounters (details depends on the regional/clinical workflow) its HPOs and it asks for registering (Step 2). The HPO will then push the triple <patUUID, patientID, url_of_registry/FHIR_endpoint, url_of_repo, hpoid> (Step 3). It is worth noticing, that, depending on the various setting, additional steps may be required to allow the GOE to connect to the HPO's Vendor Façade. At this time, the GOE knows how the opaque string patUUID having Ethereum addresses, may have documents matching a request in the given HPOs. The patient may want to use any OpenID login mechanism (e.g., Facebook, Google) to facilitate the login system. No more data is stored in the GOE.

In this case (Step 4) a Pharmaceutical institute registers himself, and submits a Clinical Trial (Step 5) to the GOE. Notably, this operation can be automatical, or it may need negotiations with the GOE (depending on the complexity of the clinical trial). Trials may have certain inclusion and exclusion criteria, some of them can be decided by the GOE when the clinical trial is submitter, some others may need further access to data, and finally some other has to be decided by the requestor. At a first stage the coordinates of the phone (during the registration phase) will only be used as inclusion/exclusion criteria (e.g., inclusion based on a geographical area). In fact, a Push Notification about the new trial (Step 6) is sent to the App. The patient is asked for a consent (Step 7) to access data for a possible eligibility check (inclusion/exclusion criteria). Additionally, a questionnaire can be sent to the patient to further refine the criteria (Steps 8 and 9). If additional data is fetched and analyzed (e.g., to check if a patient has a history of specific encounters, checked by simply inspecting CDA XMLs, Steps 10, and 11) it is evaluated in Step 12. At this stage, the final decision if to include the patient in the trial is taken and the patient is notified in Step 13 (with another Push Notification). Fitness data available already on the phone (e.g. Apple Health, or Google Fit) will be used as well.

Once the patient has been elected to participate, a BPPC consent BPPC is submitted to all the HPOs belonging to the patient (Step 14). In Step 15, the metadata of the documents are accessed. Notably that the query is by default for CDA Level 3 documents. The reason is for data anonymization. CDA Level 3 have specific fields where the patient information are located thus the anonymization process will remove those information as soon as they arrive in the memory pool of the GOE resulting in a completely anonymized data (in Step 27). The same applies for XDS metadata: patient information is removed from the specific XDS slot (Steps 16, 17). If the clinical trial requires to wait for a specific document that will be available just after the enrollment of the patient, a DSUB subscription is made: when a new document will be available, a notification will arrive to the GOE (Steps 18 and 19). In Step 20, all the metadata is collected, and in Step 21 the amount of Grapes to be transferred to unlock the data is evaluated. The amount is returned in Step 22. Pharmaceutical institue transfers the grapes to the Ethereum address of Grapevine (Steps 23). Notably this process is defined by a negotiation when the trial is submitted. By default, a Ethereum address per clinical trial is created. This way Pharma will have access to all the documents exactly when all the HPOs and all the patients replied (within a limited amount of time). Pharma can also have early access to chunks of data. For each chunk a new address will be created. Data will be unlocked as soon as the Transfer event for that address will be emitted.

In Steps 24 Pharma requests the data to be transferred. In parallel the users and HPOs receives the notification of the Transfer (Steps 25, and 26). For each document with a matching metadata a retrieve is triggered to the HPO (Step 27) and returned (Step 28). At this stage, the document provenance is evaluated in the following way. The document (assuming a CDA) is firstly anonymized as defined above. Document is canonicalized (e.g., for a CDA using XML c14n) and a Provenance W3C PROV document is evaluated. This document contains the information related to the provenance of the entire document and all its sections (e.g., lab results). This is done in Step 29. The hash of the canonicalization is then used to query a private blockchain (based on Hyperledger Sawtooth) to check for provenance. If a PROV document is found in the Sawtooth (containing only from where the document is retrieved, by whom - the GOE -, using which agent - the GOE -) it is appended in the document's XML. Otherwise a new document is firstly created, submitted and then appended to the response (Steps 30-34). At this stage, Grapes are distributed calling the Transfer ERC-20 function to all the participants, and the flow ends (Steps 35-37).

The FSM

The above UML diagram can be represented in a Non Deterministic Finite Automaton (NFA) represnted as follows.

The NFA of the GOE

The system starts with the REQUEST_WAIT state, waiting obviously for new request. When the new request arrives (Pharma_req_data) we enter in the SELECT_MATCH status where the GOE selects the potential patients matching the query from Pharma. If the query is invalid, we turn back to the initial state (Invalid_req), and if there are no matching patient, we end in the ERROR_PROCES end state. After succesfully selected the patients we change state using the Notify_patients transaction and we go in the COLLECT_CONS state. If no patient give consent, we transact to the error state using the no_cons transaction. Otherwise we move to the CONSENT_SUBM state using the submit_cnst_hpo transaction which submits all the received consents to the HPOs for which the patient is registered and known by the GOE. After requesting the metadata (req_mdata), we collect all of them and we transact to CLLECT_MDATA. If no documents are found, the no_doc_found transactions goes in the error state. Otherwise we evaluate the amount, and we notify it (ntfy_amount). We then wait for the grapes in the state AN_WAIT_GRAP. If no grapes are received in a given quantum of time, the transaction no_grapes_recv moves to the error state. Otherwise the NFA's next state is GRAPES_RECEVD. At this time w notify the patients and the hpo (ntfy_hpo_pat) and we record a new state change (PAT_HPO_NTFYD). We then retrieve the documents (retrieve_doc) and we collect and anonymize all the data (DATA_COLLECT). Notably the anonymization algorithms are pluggable. They span from simply removing the patient identifier from CDA to a more complex an AI-based solutions, TBD. If no data is returned in the retrieve, we transact to the error state using the no_data_found. Otherwise we distribute grapes (distr_grape) and we move to the GRAPES_DISTR. After sending data with send_data action, we conclude in the DATA_SENT.

We use this finite state machine to define our logs to reconstruct the state of a crashed actor. This NFA also defines the information that are logged at the GOE.

Timeline

This is a rough distribution of timelines expected for the development of the GOE.

  • Q2 2018 Ethereum development: The crowdsale and the ERC-20 token
  • Q3 2018 (Late summer, Fall) Version ready for audit and pentest
  • Q1 2019 Production (w.r.t. the Grapevine World timeline)

Contributors