First, Do No Harm. Reporting About Safety
Once a pharmaceutical product — a drug, vaccine, or medical device — has gone through the different testing phases, and the approval process with regulatory agencies, it hits the market and can be prescribed and sold. Serious adverse events can appear when the product is widely used for the first time by real patients. This relates not only to potential flaws in scientific research and problems related to regulatory approval and reporting in scientific journals. It is also sometimes a matter of numbers: If you test safety on 5,000 patients, an adverse event arising in one of 20,000 will become apparent when many more patients use the product.