Misuse of the P value — a common test for judging the strength of scientific evidence — is contributing to the number of research findings that cannot be reproduced, the American Statistical Association (ASA) warns in a statement released yesterday. The group has taken the unusual step of issuing principles to guide use of the P value, which it says cannot determine whether a hypothesis is true or whether results are important.

This is the first time that the 177-year-old ASA has made explicit recommendations on such a foundational matter in statistics. The society’s members had become increasingly concerned that the P value was being misapplied in ways that cast doubt on statistics generally.

In its statement, the ASA advises researchers to avoid drawing scientific conclusions or making policy decisions based on P values alone. Researchers should describe not only the data analyses that produced statistically significant results, the society says, but all statistical tests and choices made in calculations. Otherwise, results may seem falsely robust.

http://www.nature.com/news/statisticians-issue-warning-over-misuse-of-p-values-1.19503

ASA's Paper: http://amstat.tandfonline.com/doi/suppl/10.1080/00031305.2016.1154108