Confusion about Negative Studies

To the Editor: As Angell notes,¹ a study that is well designed and conducted makes a positive contribution to biomedical knowledge; thus, it seems wrong to call it a “negative study.” Others have requested that similar terms not be used,² I believe with good cause. What one is really concerned with is the study results, for which the term “negative study” is too broad. Generally speaking, one can obtain one of five possible results in testing a single hypothesis: (1) a “positive” association between factors of interest (in favor of the test hypothesis) that is “statistically significant,” (2) a “positive”.