Welcome back, quiz bowl participants. Our very first quiz bowl, which appeared on this site on May 5, 2011, dealt with format, style, and punctuation of units of measure. Now we’re back to delve even further into the intriguing and ever-changing world of units of measure style. The following is a sample of one of the questions that appears in this month’s AMA Manual of Style quiz on SI vs conventional units (http://www.amamanualofstyle.com/). Answer the question based on your understanding of section 18.5 of the AMA Manual of Style.
The mean 2-dimensional area of the largest metastasis was 7.2 sq in.
So, what do you think? This one isn’t really too hard. Here’s the answer (use your mouse to highlight the text box):
The mean 2-dimensional area of the largest metastasis was 46.8 cm2.
Measurements of length, area, volume, and mass are reported in metric units rather than English units. To convert square inches to square centimeters, multiply by 6.5 (§18.5.1, Length, Area, Volume, Mass, pp 794-795 in print).
Let’s try a more challenging question.
Admission laboratory tests revealed the following: serum creatinine, 0.9 mg/dL; serum urea nitrogen, 11 mg/dL; serum albumin, 39 g/L; and prothrombin time, 11.5 seconds.
Yes, this one is definitely harder. Here’s the answer:
Admission laboratory tests revealed the following: serum creatinine, 0.9 mg/dL (to convert to micromoles per liter, multiply by 88.4); serum urea nitrogen, 11 mg/dL (to convert to millimoles per liter, multiply by 0.357); serum albumin, 3.9 g/dL (to convert to grams per liter, multiply by 10); and prothrombin time, 11.5 seconds.
For laboratory values, factors for converting conventional units to SI units should be provided in the article. In text, the conversion factor should be given once, at first mention of the laboratory value, in parentheses following the conventional unit (§18.5.10, Laboratory Values, pp 797-816 in print). Although the AMA Manual of Style recommends writing out units of measure when no numbers are reported (eg, micromoles per liter), some journals may prefer to use abbreviations when listing SI conversion factors (eg, mmol/L).
Need some more practice? Subscribe to the AMA Manual of Style online and take the full quiz. If you’re new to the site, check out some of our other quizzes as well.—Laura King, MA, ELS