Study to Assess the Burden of Mild Outcomes (Physician Office Visits) Due to Influenza in the United States

Study Overview
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Brief Summary
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This is a database study to quantify the burden of multiple mild outcomes (i.e., those that result in visits to a physician's office) attributable to influenza in the United States, stratified by age group, geographic region and influenza subtype for selected influenza seasons.

Detailed Description
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This is a retrospective database study to quantify the burden of multiple mild pre-defined influenza-attributable outcomes of interest, which resulted in physician office visits for persons who were less than 65 years of age, in the United States in the relevant Marketscan Commercial database in the period from July 2000 through April 2009, and October 2010 to May 2011. The corresponding physician office visits for persons 65 years of age and older, with a mild influenza-attributable outcome of interest, in the United States that were recorded in the relevant MarketScan Medicare Supplemental database in the period from July 2006 through April 2009, and October 2010 to May 2011 were also investigated. The period from April 2009 through September 2010 is excluded to avoid the H1N1 pandemic wave.

Official Title
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Burden of Mild Outcomes Due to Influenza in the United States, July 2000 Through April 2009 and October 2010 to May 2011

Conditions
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Influenza

Intervention / Treatment
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* Other: Data collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Recorded in a Marketscan database with any of the specified diagnostic codes. Exclusion Criteria: • Missing data in any of the following fields: age, diagnosis, region or visit date.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Study Group<br>Applicable subjects less than 65 years of age identified in the Marketscan Commercial database during the period from July 2000 through April 2009, and October 2010 to May 2011 and subjects 65 years of age and older identified in MarketScan Medicare Supplemental database during the period from July 2006 through April 2009, and October 2010 to May 2011. | Other: Data collection<br>* Data collection from existing electronic healthcare databases (Marketscan Commercial database, MarketScan Medicare Supplemental database).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weekly occurrences of potentially influenza-attributable physician's office visits by age, region and season. | - All the events contained within potentially influenza-attributable office visits. - Weekly proportion of circulating influenza A and B strains determined for each season. | Up to 10 years approximately (Marketscan Commercial Database) and up to 6 years approximately (Marketscan Medicare Supplemental Database). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of Influenza vaccine content and effectiveness by season. |  | Up to 10 years approximately (Marketscan Commercial Database) and up to 6 years approximately (Marketscan Medicare Supplemental Database). | 
| Assessment of Influenza vaccine coverage by season and region. |  | Up to 10 years approximately (Marketscan Commercial Database) and up to 6 years approximately (Marketscan Medicare Supplemental Database). | 
| Assessment of Influenza B vaccine mismatch (by region and season). |  | Up to 10 years approximately (Marketscan Commercial Database) and up to 6 years approximately (Marketscan Medicare Supplemental Database). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mild outcomes, Database, Influenza-attributable, Retrospective, Influenza, United States of America (USA)