In their article "Coffee Intake and Risk of Hypertension" in the March 25, 2002, issue of ARCHIVES, Klag et al1 make a claim in their summary that seems at odds with their reported findings. In the data examined, it is shown that coffee drinking is associated with a trivial increase in average blood pressure (+0.2 mm Hg) and this finding is significant (at a 95% confidence level). It is also associated with a substantial increase in hypertension (+10%), although this finding is not significant (at a 95% confidence level). This apparent contradiction is not resolved or even acknowledged. The summary conclusion "coffee drinking is associated with small increases in blood pressure, but appears to play a small role in the development of hypertension" would therefore appear to be a notable distortion and misleading to the reader.
Rust J. The Impact of Coffee Drinking. Arch Intern Med. 2003;163(3):370. doi:10.1001/archinte.163.3.370-a