Cost of Illness Associated With Influenza in the UK

"Data of patients diagnosed with acute respiratory illness is extracted from General Practice Research Database (GPRD), Hospital Episode Statistics (HES), the Health Protection Agency (HPA), Office of National Statistics (ONS), and National Health Service (NHS) Reference Costs, during the period January 21st 2001 and March 31st 2009 inclusive.~All analyses of primary care data (GPRD) and separately for secondary care (HES) data will be repeated for all eligible patients, and the subset of patients with a linkage to additional data (HES, ONS). All analysis including secondary care data will be restricted to the subset of patients with linked HES data. Estimates of average burden per patient and total burden in the UK will be performed. Burden is defined as both resource use and cost. Annual incidence and burden will be calculated."