Reader response: Upgoing thumb sign: A sensitive indicator of brain involvement?

Abstract

In the article by Hachinski et al.,1 the upgoing thumb sign is more frequently found in patients with stroke or TIA. However, after reading the text and studying figure 2 and table 1,1 I was confused by the apparent differences in numbers of individuals. For example, the number of stroke/TIA patients is 116 in the text and 113 in table 1. The numbers in table 1 do not add up: there are 30 + 22 = 52 stroke mimics and not 55 as is stated on the upper line. The percentages and numbers in table 2 suggest a completely different distribution of patients among the 4 categories: supposing that female sex could be ascertained for all patients, the numbers (with percentages in parentheses) lead to 55 patients with mimics (37 without [of which 62% = 23 are women] and 18 with a positive sign [of which 56% = 10 are women]) and 114 stroke/TIA patients (45 without and 69 with a positive sign). In addition, neither these numbers nor the numbers quoted in table 2 are consistent with the percentages in figure 2. These inconsistencies make it impossible to judge the true value of the upgoing thumb sign.