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Service Unit Boundaries


Public Health Service
Indian Health Service
Rockville, Maryland


Effective Date:  03/25/1988


  1. PURPOSE.  To set forth Indian Health Service (IHS) policy and procedures with respect to the establishment of and changes in the boundaries of IHS-operated and tribally-operated service units.  This circular does not prescribe the procedures for redesignating the boundaries of Health Service Delivery Areas (HSDAs).

  2. BACKGROUND.  The delineation of the IHS service units during the 1980s developed along two separate courses.  There was the formal establishment of IHS service units with administrative codes in accordance with IHS Circular No. 76-6.  There was also the informal establishment of what were called IHS statistical service units.  The concept of statistical service units was developed because tribally- operated service units could not be assigned administrative codes since they were not served by a local, permanent IHS-operated facility, (i.e., managed and staffed by permanent, full-time Federal employees). Other than the assignment of the administrative code, the statistical service units that were established met all of the criteria of IHS Circular No. 76-6. Rather than continue with two classes of service units, this revision of IHS Circular No. 76-6 sets forth the same policy and procedures for the establishment of all IHS service units, both IHS-operated and tribally-operated.

  3. DEFINITION OF SERVICE UNIT.  A service unit is an administrative entity, whether operated by the IHS or a tribe, with the responsibilities for planning, managing, and evaluating the IHS program serving a defined geographic area less than that for which an Area Office is responsible.  It includes only land Within a Health Service Delivery Area (HSDA).

  4. GUIDELINES FOR DELINEATING SERVICE UNIT BOUNDARIES.  There are several factors which must be considered in the drawing of service unit boundaries: 1) population size required for the effective delivery of health services and the establishment of a comprehensive health delivery system; 2) patterns of health services; 3) operational organization; and 4) geographic and civil divisions for which data are available.

    The boundaries of service units are designed for administrative purposes in the delivery of health services, and should not be construed as conferring eligibility or setting priorities for services extended by the Indian Health Service to individual Indians within these boundaries.  Similarly, estimates of service and user population will not necessarily be the same as the total Indian population residing within the geographical boundaries (e.g., there may be non-Federally recognized Indians in the area).  This will vary with local situations.

    The service unit is the primary resource allocation entity below the Area Office level.  However, resource allocation decisions are based on the unique requirements of each service unit since service units have varying characteristics, such as number of tribes, population and workload.

    Service units may be operated by the IHS or under the authority of the Indian Self-Determination Act (P.L. 93-638) or the Buy Indian Act (25 U.S.C. 47).  Although IHS may contract below the service unit level for the delivery of a specific health service (where effectiveness, efficiency and quality considerations are satisfied), such contracts do not constitute new service units.

    1. Service unit boundaries need to be established so that the resulting geographic area and service population are of a size to realize economies of scale so that effective and efficient quality health services can be provided.  The population needs to be of sufficient size so that a network of services (with an administrative unit and other direct care programs) can be established which forms a comprehensive health delivery system for the patient.  Effectiveness, efficiency and quality considerations are to be based on the current IHS Resource Requirement Methodology (RRM) standards.  In order to achieve the optimum site for the delivery area, service unit boundaries must extend beyond reservation boundaries as appropriate, to include adjacent non-reservation territory in which eligible Indians live.
    2. Service unit boundaries should reflect as far as possible actual utilization patterns and services under the IHS program, providing that these patterns reflect an effective, efficient and quality health service delivery system that provides comprehensive health care.  The determination of health service patterns should be based whenever possible on factual evidence, such as hospital discharges and outpatient visits.  In the case of contiguous service units where service delivery areas overlap and create "gray areas" of service, residence studies should be used as a means of determining the most practical geographic location for service unit boundaries.
    3. Where services do not center around an IHS or tribally-operated facility in a uniform pattern, as in those areas where the Indian population is scattered, or services are provided through many contract facilities, Indian groups should be combined into service units according to administrative feasibility or patterns of preventive health services.
    4. To the extent that delineations do not conflict with an effective, efficient and quality health service delivery system providing comprehensive health care, service unit boundaries should be drawn to coincide with Health Service Delivery Area (HSDA) boundaries.  The next level of preference is the use of county boundaries to facilitate the use of vital statistics, population and other data which are available frequently on a county level but not for lesser geographic divisions.  In locations where this is impractical, other standard geographic or political divisions should be used such as townships and census enumeration districts, natural geographic features or traditional divisions of population groups.
    5. Service units may encompass one or multiple tribes, providing that the above criteria are met.  It may be necessary to include more than one tribe in a service unit to achieve an effective, efficient and quality health service delivery system.
    6. The entire service population of an IHS Area must be divided into service units, consistent with the above criteria.  Therefore, if a new tribe is Federally recognized, the service population for that tribe must be incorporated into an existing service unit, a new service unit established or the new territory added to an existing service unit, as appropriate.
    7. No geographic area may be in more than one service unit.
    8. All geographic areas within the funded scope of the IHS, including all areas designated ?on or near" a reservation, must be in a specifically identified service unit.  Special programs such as urban programs are to be excluded. However, there may be a geographic portion of a special program which overlaps with a designated "on or near" area and therefore is contained within a service unit.
    9. After implementation of the regulation establishing Health Service Delivery Areas (HSDAs), no service unit may include areas not so designated, and all such designated HSDAs must be included in a service unit.

  5. PROCEDURES FOR ESTABLISHING OR MAKING CHANGES IN BOUNDARIES.  Area Directors will review their service unit delineations on an annual basis and submit proposals for changes or additions to the Director, Indian Health Service, by May 31.  If approved, these changes would be effective at the beginning of the next fiscal year.  Proposals may be submitted at any time throughout the year in the case of unanticipated operational changes.  Such proposals will be accompanied by a brief description of the basis for the proposed delineations and an outline of the way the various types of health services are or will be administered, provided and utilized, including identification of the IHS, tribal and contract facilities involved.  A Census map (with enumeration districts and minor subdivisions of counties) from the latest U.S. Census also needs to be submitted which depicts the proposed service unit boundaries in relation to the existing service unit (if applicable), HSDA and county boundaries.

    The Director, Division of Program Statistics, will be responsible for reviewing proposals submitted by the Area Offices and recommending service unit boundaries to the Director, Indian Health Service.  An advisory group consisting of persons from the Division of Management Policy, Division of Legislation and Regulations, the Office of Health Programs, and other Offices in Headquarters will be designated to assist the Director, Division of Program Statistics, as needed, in evaluating factors involved in particular problem areas.

    Those approved IHS service units in which health services are provided through a permanent IHS-operated facility (i.e., managed and staffed by permanent, full-time Federal employees) will also be assigned an administrative code.  The assignment of administrative codes is the responsibility of the Director, Division of Management Policy.  The administrative code defines the Department of Health and Human Services executive branch structure.  All IHS service units, with or without an administrative code, are considered equal in terms of the IHS program.

  6. This circular revises and supersedes Circular No 76-6 dated June 8, 1976.

/Robert G. McSwain for/
Everett R. Rhoades
Assistant Surgeon General

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