“…The studies about voice analysis of depression designed various tasks (details about the tasks are shown in Additional file 3), including: 1) interview, usually originating from interview [3, 7, 8, 18–20]; 2) natural speech, in general referring to daily talk or man-machine conversation [10, 21]; 3) describe or comment picture [1, 22]; and 4) reading, normally conducted by text [5, 6, 9, 10, 23]. In addition, video is a stimulus that is commonly utilized for evoking emotion [24, 25] and could be regarded as a task in our study.…”