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  Assessment Feedback Incentives eXchange (AFIX)
Assessment Methods
Assuring Accurate Assessments

Immunization providers have a tendency to overestimate their practice coverage levels.  Accurate assessments at the provider level, however, can identify overall coverage and reveal possible service delivery problems in the practice. Understanding and accepting the assessment results are the first steps to implementing changes in policies and practices that will improve patient care. 

The objective of a good assessment is to help providers identify obstacles to immunization series completion and get their “buy-in” to make needed changes. In the real world, the selection of an appropriate assessment method depends on

  • how accessible the immunization data are

  • how easy it is to implement the method

  • the time and staff constraints at the provider and the local level

  • the number, size, and type of practices to be assessed

  • the availability of resources to support the assessment data

The Assessment Methods

The three types of Assessment Methods supported by CDC fall into two categories: Chart Based Assessments and Registry Based Assessments.  Each method has advantages and weaknesses (basically a trade-off between speed and diagnostic information) that must be weighed before selecting the “right” option for your program. The three Assessment Methods are described below within their respective category.

Chart-based Assessment

  • Standard Assessment
    The Standard method for conducting an assessment offers two options. Ideally, all records in the selected age group would be included in the assessment. This complete review of all records in the specified age range will provide the most accurate assessment results. If the total number of patients in the specified age range is equal to or less than 50, a total review is the best option.

    When the total number of patients in the specified age range is greater than 50, a Standard Assessment can be conducted using a randomly selected sample of patient charts. An estimated vaccination coverage level based on the information obtained from the charts can be calculated.

    The Standard Assessment method provides immunization coverage levels for the assessed provider site as well as diagnostic information on patients with missed opportunities, late starts, etc.

  • Hybrid Assessment
    The Hybrid Assessment method may also be used for conducting assessments. This method is available using the principles of
    Lot Quality Assurance (LQA) sampling and involves reviewing exactly 30 charts. The Hybrid method can only identify whether a provider’s coverage is above or below a selected threshold level rather than calculate an estimated immunization coverage level.

    Coverage levels can not be determined using the Hybrid Assessment method. Individual medical charts should be reviewed with the provider in an effort to highlight immunization practices that might improve coverage levels. Diagnostic information regarding missed opportunities, late starts, drop-offs, etc can only be determined by using individual medical charts. Consult the Hybrid CASA Methodology for more information. 

Registry-based Assessments

A registry based assessment utilizes data from an immunization registry. This method generally assesses a pre-defined population rather than a sample of that population. The immunization data can be analyzed with available assessment functions built into the registry (if available) or the data can be exported from the registry and imported into CoCASA for analysis.

General CoCASA Information

The Comprehensive Clinic Assessment Software Application (CoCASA) is a tool for assessing immunization practices within a clinic, private practice, or any other environment where immunizations are provided. CoCASA has data entry and import capabilities.

Immunization coverage assessments are essential for vaccination programs because they indicate how well immunization recommendations are being implemented. Assessments also provide early indicators of the presence of significant barriers to immunization and stimulate the development of improvement plans.

VFC-AFIX Initiative

In order to expand the benefits of AFIX to the private sector, which now vaccinates nearly 80% of children in the US, the National Immunization Program (NIP) launched an initiative to incorporate assessment and feedback activities during Vaccines For Children (VFC) provider site visits. This initiative links two highly successful programs - AFIX and VFC - and focuses on increasing quality assurance activities within provider offices enrolled in the VFC program.

VFC is a federal program that purchases vaccines for eligible children who meet one of the following requirements: enrolled in Medicaid; no insurance; Native American or Alaska Native; or underinsured. All states are participating in this program, which enjoys broad physician support. Over 44,000 provider sites participate in the program, primarily in the private sector. The VFC program benefits providers as well as children by reducing cost as a barrier to immunization and encouraging kids to stay in a medical home. 

VFC provider site visits are conducted to review compliance with VFC eligibility requirements and to evaluate vaccine storage and handling procedures. These VFC site visits provide an excellent opportunity to introduce and include assessment and feedback of immunization service delivery practices.

Assessment Feedback Incentives eXchange (AFIX)
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This page last modified on January 3, 2006.


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