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AFIX Assessment: Methods

Assuring Accurate Assessments

Accurate Assessments at the provider level 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

Methods Types

The two types of Assessment Methods supported by CDC are: Immunization Information Systems (IIS) Based Assessments and Chart 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 two Assessment Methods are described below within their respective category.

Immunization Information Systems-based Assessments

CDC recommends that awardees continue to work toward utilization of the Immunization Information Systems (IIS) for assessment. With the increased IIS functionality comes the ability to execute population-based assessments, utilize a Geographic Information System (GIS), and provide real-time interface with other data systems. This functionality and interfacing can streamline the process for assessment of immunization coverage.

An Immunization Information System (IIS) 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 IIS (if available) or the data can be exported from the IIS and imported into CoCASA for analysis.

Chart-based Assessments

If the immunization program (program) uses the chart-pulling method, the following are CDC’s recommendations for this method:

  1. The number of charts to be reviewed in a chart-based assessment is 50 to 200 for the same age group. 
  2. If a provider has fewer than 50 charts for the same age group, the review to include all available charts for the assessment age group. The review of all charts provides accurate assessment results and eliminates the error margin for the coverage results.

When the total number of patients in the specified age range is greater than 50, an assessment can be conducted using a randomly selected sample of patient charts and the number of charts to be reviewed should be between 50 and 200. An estimated vaccination coverage level based on the information obtained from the charts can be calculated.

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.

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