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13. Directory Service

I. Description of the Option

William L. McMullen from Mitertek recommends the use of Directory Service instead of a Unique Patient Identifier to link patient information. The Directory Service would use existing patient identifiers of legacy systems in a manner to provide linkages to records of individuals across systems. The directory service system uses patient characteristics such as social characteristics (name, SSN, address, driver license etc.) human characteristics (finger print, retina scan etc.) and other groupings such as sex, race, DOB, etc. The directory service would reconcile interactively and heuristically the proper association of the patient identification data at the current point of care with any one of the other prior points of care. This step would be supported by automated capabilities that would facilitate locating the other patient records for which a record linkage is valid. The current point of care location would then be linked with any of the other selected point of care locations by electronically exchanging their network addresses.

Mr. McMullen's method is implemented in the state of Georgia to manage access to mental health patient information. Although he is not currently involved in this project, he strongly believes that the Directory Service model can be used instead of implementing a nation-wide Unique Patient Identification System. He points out that his original Directory Service concept needs to be updated. His current recommendation consists of the internet-based Netscape Catalogue Service instead of the Directory Service. He feels a subscription based funding model similar to the internet services can be utilized and the expense shared by participating organizations. This will be less expensive than implementing a Unique Patient Identifier nation-wide.

II. Author/Proponent and Documentation

1. Mr. McMullen's Directory Service is being used by the state of Georgia to manage access to mental health patient information.
2. The method is being recommended by Mr. William McMullen of Mitertek Corporation. His past document outlining his original method is the only document available for review.

III. Compliance with ASTM Conceptual Characteristics

The Directory Service utilizes patient characteristics information such as name, SSN, address, driver license, sex, race, DOB, etc. to reconcile interactively and heuristically the proper association of the patient identification data at the current point of care with any one of the other prior points of care. It is not a Unique Patient Identifier proposal. Therefore, most of the ASTM Conceptual Characteristics are not applicable to the Directory Service.

a) Functional Characteristics

Accessible: Does not apply, not a Unique Patient Identifier proposal.

Assignable: Does not apply, not a Unique Patient Identifier proposal.

Identifiable: Does not apply, not a Unique Patient Identifier proposal.

Verifiable: Does not apply, not a Unique Patient Identifier proposal.

Mergeable: Does not apply, not a Unique Patient Identifier proposal.

Splittable: Does not apply, not a Unique Patient Identifier proposal. .

b) Linkage of Lifelong Health Record

Linkable: The Directory Service uses patient profiles and available identifiers to facilitate linkage of health records from multiple providers.

Mappable: Does not apply, not a Unique Patient Identifier proposal.

c) Patient Confidentiality and Security

Content Free: The searching and matching performed by the Directory Service utilize patient's demographic information and available identifiers

Controllable: Does not use encryption

Healthcare Focused: The Directory Service proposed by Mr. McMullen is healthcare-focused.

Secure: Encryption is not included in the proposal.

Disidentifiable: Encryption scheme to disidentify an individual is not part of the model.

Public: The patient demographic information used by the Directory Service for matching cannot be disclosed in public.

d) Compatibility with Standards and Technology

Based on Industry Standards: Directory Service is not a Unique Patient Identifier proposal.

Deployable: The Directory Service can be implemented with the existing technology. However, it is not a Unique Patient Identifier proposal.

Usable: Directory Service is not a Unique Patient Identifier proposal.

e) Design Characteristics

For nation-wide use the Directory Service model will need both a technology and administrative infrastructure. The current proposal does not include the administrative infrastructure issue. The Directory Service concept needs to be developed further. These capabilities will be subject to the appropriate specification, design and development that are yet to be organized.

Unique: Directory Service is not a Unique Patient Identifier proposal. It uses patient's social and personal characteristics for searching and matching.

Repository-based: Directory Service is not a Unique Patient Identifier proposal. It is not repository-based.

Atomic: Directory Service is not a Unique Patient Identifier proposal.

Concise: Directory Service is not a Unique Patient Identifier proposal.

Unambiguous: Directory Service is not a Unique Patient Identifier proposal.

Permanent: Directory Service is not a Unique Patient Identifier proposal.

Centrally governed: Directory Service is not a Unique Patient Identifier proposal. A Central Trusted Authority with the knowledge of the location of patient information will help the process.

Networked: Directory Service is based on telecommunication (modem) and networks.

Longevity: Directory Service is not a Unique Patient Identifier proposal.

Retroactive: Directory Service is not a Unique Patient Identifier proposal.

Universal: Directory Service is not a Unique Patient Identifier proposal.

Incremental Implementation: Does not apply. Directory Service is not a Unique Patient Identifier proposal.

f) Reduction of Cost and Enhanced Health Status

Cost-effectiveness: The Directory Service has the potential to access patient information distributed among multiple provider organizations that participate in the Directory Service. However, it is not a Unique Patient Identifier proposal and does not address all the basic functions of a Unique Patient Identifier.

IV. Compliance with Operational Characteristics and Readiness

Currently operational: The Directory Service is not a Unique Patient Identifier. It is used on a limited basis for access to mental health patient records in the state of Georgia. It is not currently operational as a Unique Patient Identifier.

Existing infrastructure: Both the administrative and technology infrastructures are not in existence for nation wide use.

Readiness of the required technology: The basic technology necessary to develop the infrastructure is ready and available. However, the application software and communication systems are yet to be developed.

Timeliness: The Directory Service is a new initiative for healthcare. The development of specifications and the final solution may require substantial amount of time.

Adequacy of information to support identification functions: The Directory Service is not a Unique Patient Identifier and it does not maintain patient identification information.

V. Compliance with Unique Patient Identifier Components Requirements

Identifier

The Directory Service is not a Unique Patient Identifier.

Identification Information

The Directory Service does not maintain a patient identification data base.

Index

The Directory Service is not a Unique Patient Identifier and it does not maintain a patient index.

Mechanism to protect, mask or encrypt the identifier

Does not use encryption

Technology Infrastructure

The Directory Service is not a Unique Patient Identifier. The necessary specifications, design and technology development are yet to be planned.

Administrative Infrastructure

The Directory Service is not a Unique Patient Identifier. Administrative Infrastructure is not addressed.

VI. Compliance with Basic Functions Criteria

The main focus of the Directory Service is to use patient's personal identification information and existing identifiers to provide linkage of records of individuals across systems. It is not a Unique Patient Identifier proposal. It does not meet all of the operational characteristics and component requirements of the Unique Patient Identifier. Therefore, its ability to perform the basic functions of the Unique Patient Identifier is significantly limited.

Identification of individuals

Delivery of care functions: The objective of the Directory Service to provide linkage of records across systems using existing identifiers and personal identification information. It does not support the positive identification of an individual required during the course of delivery of care.

Administrative functions: Does not support patient identification during the course of delivery of care for administrative functions required by practitioners, insurers, HMOs, federal health plan agencies, etc.

Identification of information

Coordination of multi-disciplinary care processes: Directory Service is not a Unique Patient Identifier that can facilitate the multi-disciplinary functions and coordination of care processes among multi-disciplinary team members.

Organization of patient information and medical record keeping: Directory Service is not an identifier that can be used for medical record keeping or the organization of patient information.

Manual and automated linkage of lifelong health records: Upon successful implementation, the Directory Service will have the potential to search and match patients from multiple provider organizations. Together with the use of a Unique Patient Identifier and record locations, it can facilitate the linkage of information from different providers toward creating a lifelong health record.

Aggregation of health information for analysis and research: Directory Service is not a Unique Patient Identifier for the aggregation of health information on the basis of diseases, treatments, outcomes, regions, etc. for research, planning and preventive measures.

Protection of privacy, confidentiality & security

Access Security: The access security of the Directory Service will depend on its final design and implementation.

Content-free Identifier: The Directory Service utilizes patient identification information for searching and matching.

Mask/Hide/Encrypt/Protect/Disidentify: The Directory Service does not include encryption.

Improve health status and help reduce cost Upon successful implementation and subject to cooperation and participation by provider organizations, the Directory Service will have the potential to search and match patients from multiple provider organizations. It will have a positive impact on the nation's health status. However, it is not a Unique Identifier proposal and its scope is limited to record linkage.

VII. Strengths and Weaknesses

Strengths:

1. Uses patient's social and human characteristics and does not require the implementation of a Unique Patient Identifier
2. Eliminates the effort, time and investment that will be required for developing and implementing a new identifier

Weaknesses:

1. Not a Unique Patient Identifier and does not meet the ASTM conceptual characteristics of UHID (meets only 3 of the 30 requirements)
2. Does not meet the five Unique Patient Identifier's operational characteristics
3. Does not meet any of the Unique Patient Identifier Component requirements
4. Does not meet most of the Unique Patient Identifier's basic functional requirements. The focus is mainly on searching and matching patient record with the use of available identification information and identifiers
5. The search is limited to participating locations.
6. Requires:

a) prior knowledge of record location and sufficient identification information. The more the availability of patient identification information the greater the success

b) provider organization's participation in the Directory Service and permission for searching for the patient, patient identifier, patient information by another computer system

c) adequate security arrangements for searching and exchanging patient information

d) development and implementation of a powerful and reliable searching and matching algorithms

7. The probabilistic matching utilized by software approaches does not assure 100% result. Discrepancies may require human intervention for resolution.

8. Currently, the Directory Service is in the preliminary stage and its fruition depends on significant planning, specification, design and development.

9. The method requires the development of an implementation plan and creation of necessary operating procedures, etc.

VIII. Potential Barriers & Challenges to Overcoming the Barriers

1. Failure to meet all of the Unique Patient Identifier's operational characteristics
2. Failure to meet all of the Unique Patient Identifier's component requirements
3. Inability to fulfill all of the basic functions of a Unique Patient Identifier
4. Development of the necessary communication technology and computer software to facilitate the exchange of information from multiple institutions with multiple identifiers for the same patient
5. Timeliness.

IX. Solutions to the Barriers:

The Directory Service is not a Unique Patient Identifier Proposal. It must include a Unique Patient Identifier solution in addition to its cross-referencing process. The solutions to barriers includes:

1. Inclusion of the missing Unique Patient Identifier's operational characteristics
2. Inclusion of the missing Unique Patient Identifier's components
3. Inclusion of the missing Unique Patient Identifier's basic functions requirements

4) Development of the Directory Service software, implementation of standards technology, communication protocols, etc.

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