INTERESTING GRAPHIC DESIGNS - RAW DATA - 22

Source: NEJM - carenini@cs.pitt.edu

PAPER CONCLUSIONS: The risk of transmission of HIV-1 from mother to infant increases when the fetal membranes rupture more than four hours before delivery. (N Engl J Med 1996;334:1617-23.)

Text:"The curve shows that four hours is a reasonable cut off point. About four hours after fetal membranes rupture, the risk of transmission increased rapidly and approxmately doubles. Further increases in this risk, expecially after 16 hours have passed, are less reliable, given the sparsity of events and the inherent limitations of the technique when it is applied to the "edges" of the distribution"

COMMENT:

• Including the raw data supports the claim about the reliability of the probability distribution
• Including raw data in the same "graphical space" can be misleading