@inbook{57220626, author={Spencer E. Harpe}, editor={Yang, Yi and West-Strum, Donna}, title={Chapter 4. Using Secondary Data in Pharmacoepidemiology}, booktitle={Understanding Pharmacoepidemiology}, publisher={The McGraw-Hill Companies}, address={New York, NY}, year={2011}, url={accesspharmacy.mhmedical.com/content.aspx?aid=57220626} }