Improving Data Quality in the Colorado Immunization Information System (CIIS)

This is a partner post by the Colorado Department of Public Health & Environment.

Also known as Colorado’s immunization registry, the Colorado Immunization Information System (CIIS) is a confidential, population-based, secure computerized system that collects and consolidates individual-level vaccination and exemption data for Coloradans of all ages from a variety of sources. Approximately 190 pediatric clinics currently report immunization data to CIIS.  For this issue of the American Academy of Pediatrics newsletter, the CIIS team has compiled some tips to help you improve and maintain data accuracy in CIIS.

Whether your Electronic Health Record (EHR) system sends patient immunization data to CIIS through an interface, or you enter that data directly into the CIIS web application, complete and accurate data is critical for several reasons.  At a clinic level, trustworthy data is needed for clinical decision making, vaccine tracking and accountability, and improved accuracy of statistical and administrative reports available within CIIS for your clinic, including the Immunization Rates and Patient Reminder/Recall reports. At a population health level, high quality CIIS data supports effective outbreak response and informs public health interventions.

The following best practices for data entry are organized by category: Patient Demographics and Patient Immunization Data.

Patient Demographics:

  • Make sure first and last names are spelled correctly. If the patient has a middle name or initial, add that to the patient’s record.
    • Regardless of length, the patient’s entire last name should be entered.
    • If the last name contains a hyphen, enter it or leave a space between the names (e.g., Test-Jones or Test Jones).
  • If an alias is provided by the patient, enter it into CIIS.
  • Make sure the correct gender is entered on the record.
  • For patients 18 years and younger, include a primary contact, such as a parent or legal guardian.
  • Verify patient eligibility for the Vaccines for Children (VFC) program at every office visit (VFC – Medicaid, Not VFC Eligible, etc.).
  • Always enter the patient’s address, unless one is not available.
  • Adding a phone number is helpful should there be a duplicate patient record in CIIS that needs to be reconciled by a CIIS Administrator.


Searching for Patient Records in CIIS

It is also important that you do a thorough patient search in CIIS before adding a new patient record. This prevents duplicate patient records from being entered in CIIS and increases the quality of patient care by reducing the chance of over-vaccinating a patient.  Sometimes searching for a patient in CIIS can be challenging, so we included a few tips to help you search more effectively:


  • To search by the patient’s name, start by entering the first two or three letters of the patient’s first and last name.  If the system displays several records that meet these search criteria, you can adjust your search by adding the patient’s date of birth.


  • If you don’t find the patient you are looking for, then try entering the entire first name and date of birth.


Don’t give up after your first attempt to search for a patient! There are over 6.6 million patients in CIIS, so you may need to try a few different methods before you are able to locate the patient for whom you are searching.

Patient Immunization Data

According to the Centers for Disease Control and Prevention (CDC), health care providers are required by law to record certain information in a patient’s medical record. This record can be in electronic or paper form. Health care providers who administer vaccines covered by the National Childhood Vaccine Injury Act (NCVIA) are required to ensure that the patient’s permanent medical record indicates:¹

  • Date of administration
  • Vaccine manufacturer
  • Vaccine lot number
  • Name and title of person who administered vaccine and address of facility where permanent record will reside.
  • Vaccine information statement (VIS)
    • Date printed on VIS
    • Date VIS was given to patient or parent/guardian

Best practice documentation also includes:

  • Vaccine type
  • Route
  • Dosage
  • Body Site
  • Vaccine refusal, if applicable

Historical Patient Immunization Data

According to the Advisory Committee on Immunization Practices (ACIP), when entering historical immunization data, providers should only accept written, dated records as evidence of vaccination. With the exception of influenza and pneumococcal polysaccharide vaccines, self-reported doses of vaccine without written documentation should not be accepted.

If you have questions or are interested in joining CIIS, please contact the CIIS Help Desk at (303) 692-2437, option #2, (888) 611-9918, option #1, or