Second, the authors used a single item to measure affective experience. They present no data to suggest that this item has suitable test-retest reliability in their group. Both the Affective Lability Scale and the Affect Intensity Measure, the two scales used in our study, have well-documented test-retest reliability (0.84 for the global Affective Lability Scale and 0.81 for the Affect Intensity Measure). With no evidence of test-retest reliability, the most parsimonious explanation of variance over time in scores in patients with stable symptoms is error variance. Error variance due to test-retest unreliability, by definition, cannot correlate with systematic variance associated with reliable scores. Thus, the lack of correlation between an index of error variance (affective lability) and reliable scores on the Affective Lability Scale is completely expected and cannot address the issue of the scale’s validity.