Then, the patient can receive free care or referrals to specialists from the doctor. GPs thus can provide comprehensive data regarding patients with a variety of conditions, from a wide range of demographic groups. Currently, 3,500 GP practices, encompassing a population of 23 million patients, contribute to the national QSurveillance database. The system is the largest and most regularly updated health tracking system in the world (National disease surveillance, 2009, BJCIM). The system can respond effectively to health alerts. For example, given concerns over the swine flu epidemic upon the horizon, "the QSurveillance primary care tracking database has increased the level of detail" in its regular weekly and daily reports to government and health authorities. Daily reporting now includes: "patients reporting flu-like symptoms in the last day, patients with flu who have been prescribed antivirals, patients prescribed antivirals without a confirmed flu diagnosis, hospital admissions related to flu, the uptake of flu vaccinations, and the uptake...

The data is reported through a wide range of qualitative examinations, which limits self-reporting error by patients, yet circumvents the limits of the 'blunt tools' of birth and death databases that only track a few disease-related factors.
Limits: The system seems best deployed in a nationalized system of healthcare, given the comprehensive nature of generalized practice in the UK, and the close relationship between patients and GPs.

Works cited

National disease surveillance system launches more detailed swine flu reports (2009 17 July).

BJCIM News. Retrieved October 6, 2009 at http://www.bjhcim.co.uk/news/2009/n907042.htm