Study to Analyze the Clinical and Cost Impact of Complete and Incomplete Rotavirus (RV) Vaccination

Clinical and Cost Impact of Complete and Incomplete Rotavirus Vaccination

This study aims to estimate the clinical and cost impact of RV vaccinations (both Rotateq® and Rotarix®) among children aged less than 5 years using insurance claims data from commercial plans and Medicaid low-income population. The impact of incomplete and complete RV vaccination will also be examined, overall and stratified by age (e.g., 6 weeks to 8 months, 8 months and onwards ) and calendar time of RV vaccination (e.g., 2006 onward).

Insurance claims data from the MarketScan Commercial Claims and Encounters Database {MarketScan Commercial (2000-2011[Q2])} and the MarketScan Multi-State Medicaid Database {Marketscan Medicaid (2002-2010)} will be analyzed separately; no merging of the databases will occur.

The claims data extracts are fully de-identified and compliant with the Health Insurance Portability and Accountability Act of 1996 (U.S.) (HIPAA).

For children who received at least 1 RV vaccine dose within the Advisory Committee on Immunization Practices (ACIP)-specified vaccination window of 6 weeks to 8 months old, their observation time will be divided into three RV-vaccinated cohorts: any RV vaccination before 8 months (i.e., during the vaccination window between 6 weeks and 8 months old); complete RV vaccination (i.e., after 8 months old); and incomplete RV vaccination (i.e., after 8 months old). For children who did not receive any RV vaccine dose within the vaccination window, their observation time will be divided into four control cohorts: historical (i.e., before RV vaccines were available) unvaccinated on/before 8 months old; contemporary (i.e., after RV vaccines were available) unvaccinated on/before 8 months old; historical unvaccinated after 8 months old; and contemporary unvaccinated after 8 months old.

Inclusion Criteria:

• Continuously enrolled from birth. (Note: Due to the absence of birth dates in insurance claims data, this inclusion criterion will be met if a child's year of first enrollment and year of birth are the same. If so, then the date of first enrollment will be used as proxy for date of birth.)
• Received both medical and pharmacy benefits.

Exclusion Criteria:

• Enrolled in capitation-based health plans.
• For MarketScan Commercial, residence in states with universal vaccination programs that include the RV vaccine or where RV vaccine inclusion cannot be ascertained (i.e., Alaska, Idaho, Massachusetts, Maine, North Dakota, New Hampshire, New Mexico, Oregon, Rhode Island, Vermont, Washington, Wisconsin, and Wyoming).
• Lost to follow-up or had RV prior to 6 weeks of age.