Updates to the AMA Manual of Style

Effective January 18, 2012, our preference for "Web site" will be changed to a preference for "website." (Section 10.2, page 372 in the print.) We will also use "webcast" for "webcam." Caps will be retained on mention of World Wide Web, however. This change was made January 18, 2012.

In section 15.5 (Section 15.5, page 583 in the print), Equipment, Devices, and Reagents, we will no longer require the inclusion of the location of the manufacturer. This is so easy to look up online, should anyone desire more specific details, that we believe it is not necessary to continue to require this. This change was made October 4, 2011.

Although our style manual recommends (Section 20.9, page 888 in the print) that "[expressing] P to more than 3 significant digits does not add useful information to P<.001," in certain types of studies (particularly GWAS [genome-wide association studies] and other studies in which there are adjustments for multiple comparisons, such as Bonferroni correction, and the definition of level of significance is substantially less than P<.05) it may be important to express P values to more significant digits. For example, if the threshold of significance is P<.0004, then by definition the P value must be expressed to at least 4 digits to indicate whether a result is statistically significant. GWAS express P values to very small numbers, using scientific notation. If a manuscript you are editing defines statistical significance as a P value substantially less than .05, possibly even using scientific notation to express P values to very small numbers, it is best to retain the values as the author presents them. This change was made August 16, 2011.

In the list of abbreviations (Section 14.11, page 504 in the print), an asterisk should be added after CI to indicate that this abbreviation no longer needs to be expanded. This change was made July 27, 2011.

In April 2010, the WHO Nomenclature Committee for Factors of the HLA System introduced a modification of the nomenclature outlined in the manual; the new nomenclature introduces delimiters in the form of colons, which removes the restriction of only allowing 99 alleles in 1 group. Hence the former HLA-DQB1*0503 is now expressed as HLA-DQB1*05:03 (Tait BD. The ever-expanding list of HLA alleles: changing HLA nomenclature and its relevance to clinical transplantation. Transplant Rev [Orlando]. 2011;25[1]:1–8.). This change was made March 29, 2011.