Error. If you're an epidemiologist, you work, live, and breathe it. Some of us loathe it as the source of all our negative studies. Some of us embrace it as a reminder that the universe is, well, just imperfect. And maybe that's OK. But however you feel about error, you best be reporting it in your research studies. And how you report it matters. For a full discussion, check out my latest methods man blog post.