Blockchain and Interoperable Standards for Ehr - a Comprehensive Review

Turkish Journal of Physiotherapy and Rehabilitation; 32(2) ISSN 2651-4451 | e-ISSN 2651-446X

BLOCKCHAIN AND INTEROPERABLE STANDARDS FOR EHR - A COMPREHENSIVE REVIEW

Faheem Reegu1, Salwani Mohd Daud2, Shadab Alam3* 1, 2 Razak faculty of technology and Informatics, Universiti Teknologi Malaysia, Malaysia 3College of Computer Science & IT, Jazan University, Jazan, KSA Email: [email protected], [email protected], [email protected]

ABSTRACT

The focus has remained on determining and reviewing the interoperable standards in electronic health records (EHR) while determining which standard is best for interoperability. For this purpose, the research identified that the current state of interoperability is not up to the required standard, so numerous issues are experienced in managing electronic health records. In addition, the research identified numerous standards being used for interoperability, including OpenEHR, OpenEMR, OpenMRS, GNU Health and OSHERA VistA. It can be argued that the use of HL7 and its different versions can play an instrumental role in the integration of the healthcare environment. It can be further advanced by harmonizing different standards in reference to Information Communication Technology and advanced technologies like Blockchain to ensure integration between healthcare systems and their respective applications. It will prove to be beneficial in the transparent exchange of healthcare information.

Keywords-EHR; electronic health records; HL7; Interoperability

I. INTRODUCTION Approximately $30 billion was earmarked in funds owing to the 2009 Health Information Technology for Economic and Clinical Act (HITECH) to stimulateElectronic Health Records (EHR), which has primarily been embraced by the healthcareservice providers in the USA[1]. In this context, it has been suggested about it is done through the 'Meaningful Use' program, and this effort led to aconsiderable increase in the use of EHR in healthcare and by the providers. Only 9 per cent of the acute care hospitals were found to have basic EHR, compared to the forecast of 96 per cent by 2015 [2]. However, it has been recognized that even with the increase in the health records being digitized, the sharing and dissemination of the electronic health data among the providers and different hospitals have lagged behind in reference to EHR adoption, which [3] and[4]attributed to multiple reasons ranging from privacy-related concerns to the technical and operational issues. Irrespective of this aspect, the healthcare system has grown exponentially during the past decade. The hospitals or the primary care organizations have moved from the use of isolated software systems to more complex and advanced systems that have supported and facilitated the continuous medical processes. In particular, it has been argued that these solutions have resulted in the inclusion of multiple healthcare institutions and professionals and has allowed them to utilize the ubiquitous computing healthcare environments[5]. In this interactive environment, the need of looking at the information sharing among the healthcare software systems have gained significant momentum, which is quite evident in the findings of [6]and [7]that reflected the availability of the relevant patient clinical data that has helped in improving the healthcare's delivery and quality of care.

On the other hand, it was recognized about interoperability with respect to healthcarefocused on the exchange of data between different business entities; for instance, the Healthcare Information Exchange (HIE) has enabled the hospitals and their systems to engage in sharing the information statewide[8]. However, the technologically advanced era has pushed topatient-driven interoperability, where the health data exchange is patient-driven as well as patient-mediated. However, this has also led to some significant challenges and requirements surrounding privacy and security and the incentives and governance, which [9]argued to be still prevalent because they are unsolved for the traditional interoperability. In this context, [10]suggested Bitcoin is a novel technology that can help improve interoperability because of its appeal to the healthcare data due to its emphasis upon not just www.turkjphysiotherrehabil.org 3651

Turkish Journal of Physiotherapy and Rehabilitation; 32(2) ISSN 2651-4451 | e-ISSN 2651-446X sharing, but also the distribution and encryption of the data so that the potential breaches can be reduced. In this work, the focus has remained on determining and reviewing the interoperable standards in electronic health records (EHR) while determining which of the standard is best for interoperability.

II. CURRENT STATE OF INTEROPERABILITY AND EHR According to the Health Information and Management Systems Society, interoperability has been defined as the capability of the software and systems to converse and exchange the data while using the exchanged information for a greater purpose[11]. In the case of healthcare, this interoperability has been argued to have numerous benefits; for instance, [12]suggested the improvement in operational efficiency and the amount of time spent on administrative tasks because of the well-communicating system. It can reduce the need to manually enter the data within the system due to the information being faxed, whereas [13] and [14]suggestedreduced duplication in the clinical interventions, which can significantly reduce the overall health system cost. In fact, the study further elaborated that interoperability can help significantly reduce waste while exponentially improving the quality of care and patient safety that can be achieved by decreasing the exposure of the patients to radiations or invasive procedures. However, if these results are taken into account, it can be identified that mixed results have been shared by the empirical studies that have specifically focused on the interoperability implementation; for instance, [8]identified the interoperability's overall goal at state-level HIEs was to improve the cost-effectiveness while ensuring inclusive clinical care. The interoperability setting in healthcare is centred around businesses like pharmacies, private clinics, and hospitals. The data is generated in silos within the information system responsible for creating it. A prominent example of it is embedded in the electronic health records within the hospital, which [15]suggested is the result of the motivation of financial incentives or the regulatory pressures that are generally to encourage to work on improved and better health data liquidity.

In this context, [16]reflected on 21CCA that has placed a strong emphasis on sharing data, and [1]suggested that the groundwork for the statewide exchange of health information has been laid by the HITECH, but this requires significant funding. Given this situation, the health data of the individual patient has become scattered across numerous system, and no particular institution has shown interest in having a complete picture. Even with higher interoperability between different system, it can be argued that there would still be some missing data like lifestyle behaviour, the personal device monitoring data and even the social determinants of the health, as the patient generates these. In [17]and [18][19], in this context, elaborated about the EHR representing the patient because of the close approximation that may offer a complete picture in one place. It might be the reason that significant interest has been given to gaining additional data in reference to EHRs. It implies that the limitations of the EHR can be particularly resolved by including data like the behavioural and social determinants of health. However, the most concerning aspect is regarding the challenges associated with interoperability, which persists due to the operationally challenging exchange between different institutions as it requires an optimal level of collaboration between the involved entities.

Further,[20][21]elaborated on the operational and strategies issues in data sharing agreements and the matching algorithms for the complex patients and the government rules, which the researchers argued must be agreed upon to ensure the data exchange. The challenges are not just operational in nature, but many technical hurdles are also there; for instance, the entity and transactional authentication has been suggested to be robust and should be a repeater for every entity-to-entity relationship. There is also a need for threshold monitoring and anomaly detection requirements; meanwhile,[22]suggested the data exchange security presented to be of vital information while ensuring that the data exchange standards are optimally met like CDA or FHIR.

On the contrary, recent studies have indicated the burst of energy towards bringing improvement in the patients' abilities to access their own health data, but there has been ambiguity about whether or not the patients must be able to access their health data and records. The article [23]presented the case of HIPAA under which the covered entities are responsible for providing accessibility to the individuals, but this only occurs upon the requests generated by the individual. However, there isa particular exception, like the psychotherapy notes are excluded from the information[24]. Though organizational Health Information Management offices have generally handled this, the accessibility to the electronic data has now been heavily regulated inMeaningful Use. According to [25], the patients can view, download and transmit their health information and have accessibility to the health information through API, which also acts as a requirement for the EHR system certification[26][27].

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Turkish Journal of Physiotherapy and Rehabilitation; 32(2) ISSN 2651-4451 | e-ISSN 2651-446X

III. INTERNATIONAL STANDARDS ORGANIZATION The definition of electronic health records (EHR) varies from standard to standard, but the International Standard Organization's Technical Committee (ISO/TC 215) directly deals with the international standards body – Health Informatics – hasfocused on achieving interoperability and compatibility between the independent healthcare systems. Being a relatively new standards body, numerous set of new standards have been procedures and the use of international standards from HL7, DICOM, and CEN. The following section has introduced the new standards given the fact that these are explicitly concerned with EHR interoperability.

ISO/TR 20514 Electronic Health Record (EHR) content has been defined under ISO/TR 20514 and the context and structure to clarify EHR usage. Basic-generic EHR is used to define the structure, which has enabled the broader applicability of given EHR structures while clarifying the wide range of EHRs and EHR systems in reference to their existing and future structures and types. The definition of the basic-generic EHR has been supplemented based on the detailed definition stated in the following;

The ability to share the health information of the patient between EHRs' authorized users

The ability to work towards integrated healthcare through continued support, efficiency and quality

ISO/TS 18308 It is among the new standards offering information related to the architectural requirements of EHR systems but does not offer any specification in reference to the structures, i.e. ISO/TS 18308, ISO/TC 215. In addition, the process in reference to the assembling and collating of technical and clinical requirements for EHR architecture has been laid down in ISO/TS 18308 for optimal level of support, usage, sharing and exchanging of EHRs in health sectors across the globe, in addition to the application of healthcare delivery models. The standard can be optimally used by the EHR architecture standards' developers like CEN EN13606 and further indicate reference architectures like openEHR.

ISO/TR 18307 The main requirements for the achievement of compatibility and interoperability have been discussed in this standard, which entails information about trusted health information interchange between the healthcare system and the software applications. This standard has specified the need for interoperability as a healthcare community need specifically given the subject of care and reference to the healthcare provider organization, healthcare professionals and the business units, and the delivery networks. In addition, it has also provided the criterion for the standards' implementers and developers so that communication in the healthcare domain can be improved. From this perspective, it can be argued that the foundation for the healthcare information interchange must be trustful, as mentioned in the ISO TR 18307.

IV. EHR SYSTEMS AND STANDARDS Open source EHR systems are commonly available to healthcare provider organizations and healthcare as a whole, but these have been selected in reference to their global website ranking and based on the reach identification and the popularity of the open-source EHR system yearly. Based on this very aspect, the open- source EHR systems selected include; OpenEHR (Open Electronic Health Record), OpenEMR (Open Electronic Medical Report), OpenMRS (Open Medical Record System), GNU Health and VistA. In this context, it is worth mentioning that these EHR systems have been selected irrespective of their implementation,whether in primary care or the community hospital or any other hospitals. These have been selected based on their respective standards and the archetype like OpenEHR. The purpose here remains on comparing the interoperability of these systems; as presented in the following table 1;

TABLE 1: Analysis of EHR standards based on Interoperability criteria Interoperability Criteria OpenEHR OpenEMR OpenMRS GNU OSHERA Health VistA Transition of care None Yes Partial None Yes Reconciliation of clinical None Yes Yes Yes Yes information Clinical data support Partial Yes Partial Partial Yes www.turkjphysiotherrehabil.org 3653

Turkish Journal of Physiotherapy and Rehabilitation; 32(2) ISSN 2651-4451 | e-ISSN 2651-446X

Resources for patients None Yes None None Yes Electronic prescribing Yes Yes None Yes Yes Inclusion of lab tests and Yes Yes Partial Partial Yes results/values Transmission of e-lab test and Yes Yes Yes Yes Yes results/values to ambulatory providers Portability of data None Yes Partial None Yes Measures for clinical quality Partial Yes Partial Yes Yes View, download and transmit None Yes Partial None Yes to the third party Clinical summaries Partial Yes Yes None Yes Transmission to immunization None Yes None None None registries Transmission of syndromic None Yes Partial None Yes surveillance to public health agencies Transmission of the lab results None Yes Partial None Yes to public health agencies Optional transmission to cancer None Yes None None Yes registries

Data Portability and clinical quality measures are also important in reference to the EHR systems and their respective standards. In this context, it has been identified that OpenEHR has been supported and facilitated by the ZH healthcare coordination module. In contrast,OpenMRS use the Clinical Document Architecture (CDA) standards for exporting the data. In the case of VistA, popHealth has an important role, as it helps in fulfilling the data portability, whereas numerous quality measures are taken into account in OpenEMR. It is the reason that the following table 2 has offered a comparison in reference to the security and privacy-focused meaningful use criteria;

TABLE 2: Analysis of EHR standards based on security and privacy focuses Security and Privacy OpenEHR OpenEMR OpenMRS GNU OSHERA Focuses Health VistA Authenticate, access Yes Yes Yes Yes Yes control and authorize Tamper resistance and None Yes Yes None None auditable events Audit reports Yes Yes Partial None Yes Amendments None Yes None None Yes Automatic logoff None Yes None None Yes Emergency accessibility None Yes Yes None Yes Ender user device None Yes Partial None None encryption Integrity Yes Yes Yes Yes Yes Optional disclosure of None Yes None None None accounting

Functionality also holds significant importance when considering which open-source system is to be considered in healthcare, and a brief comparison of the core features (functionality) among the different open-source systems in relation to their standards have been presented in the following table 3;

TABLE 3: Analysis of EHR standards based on functionalities Functionality OpenEHR OpenEMR OpenMRS GNU OSHERA Health VistA Health Information and data Yes Yes Yes Yes Yes Results management Yes Yes Yes Yes Yes www.turkjphysiotherrehabil.org 3654

Turkish Journal of Physiotherapy and Rehabilitation; 32(2) ISSN 2651-4451 | e-ISSN 2651-446X

Order management/order Yes Yes None None Yes entry Decision support Yes Yes Yes Yes Yes e-communication and None Yes Yes No Yes connectivity Patient support None Yes None None Yes Administrative processes Yes Yes Yes Yes Yes Population health None Yes Partial None Yes management and reporting

In reference to the aforementioned aspects in the table, it can be argued that the harmonization between standards and the convergence in some cases can be proved to be significantly important in the health information systems interoperability within and between countries. This harmonization can be ensured in the current areas regarding data type, i.e. CEN 13606 Reference Model, HL7CDA, and CEN/OpenEHR archetypes with the Templates of HL7. In particular, it has also been identified that the CEN13606 has been used in the OpenEHR Reference Model, which is also used in HL7CDA. It makes it quite evident that there is some harmonization already existing between standards.

By taking account of the harmonization, it became essential to determine which standard had the highest interoperability standards. It has been presented in the following table 4, which has helped in confirming that HL7 and HITECH have more interoperability properties.

TABLE 4: Analysis of EHR standards based on properties of interoperability Properties of CEN13606 CEN OpenEHR HL7 HITECH interoperability Better Workflow Yes Moderate Yes Yes Yes Reduced Ambiguity Moderate Yes Yes Yes Yes Improved Quality of Care Yes Moderate Moderate Yes Yes Reliability Moderate Yes Yes Yes Yes Accuracy of Information Moderate Moderate Yes Yes Yes Shared Security and Privacy Moderate Yes Moderate Yes Yes

V. BLOCKCHAIN TECHNOLOGY 5.1 Role of Blockchain in Patient-driven Interoperability Blockchain can play an instrumental role in interoperability owing to the exchange of data digitally, which means that the platform can function without requiring a traditional intermediary[28][29]. There is no doubt about the health data living in numerous systems and sharing the data that needs multiple collaboration points between the entities. In the technologically advanced era, interoperability has been identified to have become more patient- centric, which has increased the possibilities of leveraging Blockchain technology for facilitating the exchange of data while giving the patients greater control with respect to their data[30][31]. In this context, the features of Blockchain that can help with patient-driven interoperability have been presented in the following table 5;

TABLE 5: Blockchain features and their role in patient-driven EHR interoperability Blockchain Features Application of Patient-Driven Interoperability Digital Accessibility The storage of clinical data can be linked with the public key of the patient. Rules The properties of the Blockchain can be appropriately used by the patients, like smart contracts, through which they can assign accessibility rules for the data. Data Aggregation The patient can connect with numerous healthcare institutional interfaces while enabling them to share their Blockchain public key so that the data can be securely transmitted to them. Data Liquidity The sensitive clinical data like the code status or the medication allergies can be published through public Blockchain, ensuring liquidity and ready access to the information as appropriate.

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Patient Identity Offering public keys to the patients to manage their data can be ensured through the multi-sig wallet or mobile devices. The public key infrastructure (PKI) can be used to establish the identity of the patients and the clinical data being retrieved by them or the addition of new information. The use of PKI can help the institutions and providers to remain confident about the generation of the data from the patient. Data Immutability The metadata or the clinical data should be securely distributed to ensure accessibility to multiple entities while ensuring integrity. It can help in leaving an audit trail so that the malicious actor can be identified. The application of the append-only model of Blockchain can help ensure that all the providers would have accessibility to the information to get the clinical picture.

5.2 Challenges and Obstacles to Blockchain-enabled Patient-driven Interoperability Some of the challenges and barriers that may affect the Blockchain-enabled patient-driven interoperability has been presented in the following table 6, in addition to the strategies through which these challenges can be mitigated;

TABLE 6: Challenges and Obstacles to Blockchain-enabled Patient-driven Interoperability Challenges and Mitigation Strategies Barriers Volume of Clinical Focusing on data exchanged based on the summary of the clinical data; Data for instance, the report of radiology can be shared instead of sharing full DICOM images Intensive validation through permissioned Blockchain that can help in effectively handling voluminous data transactions in a timely manner Blockchain scaling methodologies to integrate new technology and to research additional features Security and Privacy Minimizing public exposure by working on member-only Blockchain consortium – Authorized/Permissioned accessibility Off-chain data storage and on-chain data and metadata accessible to authorized personnel Engagement of Introduction of patient-friendly application through which the Patients intermediaries can provide access to the patients with respect to their own records Incentives Federal incentives and supports for expanding the API coverage like the VA data pledge Investing in API infrastructure based on the competitive pressure to work on API-enabled systems while encouraging the non-enabled systems to work on it as well Value for reimbursement association with open data

VI. CONCLUSION Itcan be concluded that EHR interoperability has become a necessity. The patients and the healthcare providers can access the data in a timely and cost-efficient manner, but this can become a challenge given the different standards and the open-source EHR systems based on them. For instance, it was identified that CEN 13606 Reference Model, HL7CDA, and CEN/OpenEHR archetypes with the Templates of HL7. In particular, it has also been identified that CEN13606 has been used in the OpenEHR Reference Model, which is also used in the HL7CDA standard. Suppose this is to be taken into account. In that case, it can be argued that the use of HL7 and its different versions can play an instrumental role in the integration of the healthcare environment, and this can be further advanced through the harmonization of different standards in reference to Information Communication Technology. Additionally, advanced technologies like Blockchain are used to ensure integration between healthcare systems and their respective applications, proving beneficial in the transparent exchange of healthcare information.

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