About Adolescent Immunization Rates from NIS and MIIC

Detailed description of the differences between adolescent immunization rates from the National Immunization Survey (NIS) and the Minnesota Immunization Information Connection (MIIC). Updated 2/14

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On this page:
Source
Who is assessed?
How are the rates generated?
Are there differences in how vaccine coverage is defined?
How valid are the rates?
How current are the rates?
Additional resources

Source

National Immunization Survey (NIS) Minnesota Immunization Information Connection (MIIC)
  • Centers for Disease Control and Prevention (CDC).
  • Minnesota Department of Health (MDH).


Who is assessed?

NIS MIIC
  • A random sample of U.S. adolescents aged 13 through 17 years.
  • Sub-analysis available by age, state, some local areas, race/ethnicity, poverty status, and rural versus urban residence.
  • Minnesota adolescents ages 13 through 17 years with 2 or more non-influenza immunizations in the MIIC immunization registry.
  • Sub-analysis available by county and by other variables as requested and as available.


How are the rates generated?

NIS MIIC
  • Minnesota rates are based on a surveyed sample of approximately 300 Minnesota adolescents aged 13 through 17 years old.
  • The CDC contacts a random sample of families by phone to ask about their adolescents vaccination histories and checks this information against providers' vaccination records.
  • Calculations are based on MIIC records of approximately 128,000 Minnesota adolescents, ages 13 through 17 years, who have 2 or more non-influenza immunizations recorded in MIIC.


Are there differences in how vaccine coverage is defined?

NIS MIIC
There are differences in how the two data sources define coverage with Tdap, meningococcal, and HPV.
  • Tdap coverage refers to 1 or more doses of the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis since the age of ten years.
  • Tdap coverage refers to 1 or more doses of the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis at any age.
  • Meningococcal coverage refers to 1 or more doses of meningococcal conjugate vaccine or meningococcal vaccine of unknown type.
  • Meningococcal coverage refers to 1 or more doses of quadrivalent meningococcal conjugate vaccine.
  • HPV 3-dose series completion refers to the percentage of adolescents who have received 3 doses among those who have received at least one HPV dose, with the first dose 24 or more weeks before the interview date.
  • HPV series completion refers to 3 or more doses of HPV vaccine among those who had a first dose ≥ 6 months before assessment date.


How valid are the rates?

NIS MIIC
  • Minnesota rates are based on a surveyed sample of approximately 300 Minnesota adolescents age 13 through 17 years old.
  • Each estimate is accompanied by a "confidence interval," indicating 95 percent likelihood that the true rate falls within this range.
  • Accuracy of the NIS coverage estimates is affected by:
    • Survey design,
    • Statistical adjustments used in calculating rates, and
    • Parental and provider knowledge of adolescent vaccination history.
  • Calculations are based on approximately 128,000 Minnesota adolescents age 13 through 17 years old with 2 or more non-influenza immunizations in MIIC.
  • MIIC data may underestimate the actual percent of adolescents receiving vaccines because:
    • Health care provider participation in MIIC is voluntary,
    • MIIC may include adolescents who have moved and
    • Cross border-state immunization data exchange is limited to Wisconsin.
  • Although approximately 85-90 percent of Minnesota health care providers routinely submit immunization data to MIIC, not all those who do report every dose of vaccine administered or historical immunization reported by the patient.
  • Also, when an adolescent moves out of Minnesota his or her MIIC record may not be updated and the adolescent would still be included in the denominator used to calculate the proportion of adolescents receiving immunization.
  • Finally, data exchange with border state immunization information systems is currently limited to Wisconsin. Vaccinations received in Wisconsin by Minnesota residents are in MIIC but there is no similar data exchange with North Dakota, South Dakota, or Iowa at this time.


How current are the rates?

NIS MIIC
  • NIS surveys are conducted throughout the calendar year and each year's results are published in the fall of the following year.
  • Rates reflect immunization practices 2 to 4 years in the past.
  • MIIC rates are calculated based on records of adolescents aged 13 through 17 years as of the assessment date. Thirty days are allowed for data entry into the registry.


Additional resources

 

Updated Tuesday, February 11, 2014 at 04:47PM