From IMS' website:
What do you mean by "IMS HEALTH Audited Sales"?
IMS HEALTH pharmaceutical audits for individual countries serve as the main source of comparative sales data on the pharmaceutical industry. The audits are continuous, periodic market surveys based on statistically representative samples, the data from which provides regional and national estimates. In the major countries, the pharmaceutical audits incorporate transaction data from wholesalers, giving rise to a near-census of the retail market. back
Where does the data for IMS audits come from?
The huge breadth of information brought together in this service is gathered from several sources then linked, collated, checked, verified and edited.
Sales Data
Each country audit records the data according to local requirements. Therefore the way data is collected and held will vary from country to country. In the European countries and the USA, the majority of pharmaceuticals are dispensed or sold mainly through retail pharmacies and drug stores. Thus sampling at the retail pharmacy level in such countries will represent a major proportion of the total market.
The audits provide a comprehensive record of purchases of pharmaceuticals in each country. A number of retail pharmacies and wholesalers are chosen for sampling (sample size) and sales data is collected by IMS HEALTH on a regular basis. This data is then projected to estimate sales for the total number of retail pharmacies in a country (referred to as the universe). With some variation in each country, the sales estimates shown represent direct and indirect purchases by retail pharmacies from pharmaceutical wholesalers and manufacturers.
It should be noted that, whilst IMS HEALTH data is the most comprehensive source available to monitor sales through retail channels, some products are more widely distributed and used in a hospital or clinic environment (e.g. oncology, diagnostic or specialist anti-infective treatments). For such products, IMS HEALTH retailer-based audits do not provide comprehensive coverage, and supplementary data sources will be required to project these data to a total universe for these specialist products. Contact us for more information.
Not a complete answer - but it does confirm that their process for hospital sales is different.
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