It appears from these data that a small error occurred in calculating the main outcome: Table 1 and the P value for comparing the decrease in Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores between treatment and control indicate the baseline Y-BOCS score of the third patient in the treatment group (ATa3) was not 36 but 30. With a follow-up score of 22, the decrease was 26.7%, rather than 38.9%, as stated in Table 2. Apparently, however, Lopes et al concluded from the latter figure that patient 3 was a responder because the decrease exceeded 35%. Without this patient, the number of responders under GVC stands at 2 of 8, with no responder among controls (Fisher exact test: P = .47). The absolute risk reduction, therefore, is reduced from statistically significant 37.5% (95% CI, 4% to 71%) to 25% (95% CI, −5% to 55%; nonsignificant), and number needed to treat increases to 4 (95% CI, 1.7 to ∞). Given group sizes of 8, Y-BOCS score change, when compared as a continuous variable, should be analyzed using the exact Mann-Whitney U test and not its asymptotic version.3 Thus, P slightly rises from .046 to .050 (or to .0499, to be exact). Similarly, when recalculated, the P value for change in Dimensional Y-BOCS score increased from 0.01 to 0.02. These differences are not entirely moot in a study with a host of outcomes and not adjusted for multiple tests. As a consequence, corrected figures for both dichotomous and continuous outcomes (calculated with Open Epi4 and SPSS version 22 [IBM]) suggest that chance cannot be ruled out as a factor in explaining the results.