ABSTRACT: The number of scientific journals has become so large that individuals, institutions and institutional libraries cannot completely store their content physically, and much less so intellectually. In order to prioritize the choice of quality information sources, librarians and scientists are in need of reliable decision aids. The "impact factor" is the most commonly used assessment aid in the decision-making process of which journals to contribute to, or to retrieve knowledge from. It is also an often misunderstood tool. This narrative review explains how the impact factor is calculated, how bias is introduced into the calculation, which questions it can or cannot answer, and how different professional groups can benefit from the information that the impact factor provides.
Check it out. (Okay, if you're not a librarian, you probably won't want to. But librarians probably would.)