Content-based validity evidence of the Acute Voice Fatigue Self-Perception Scale (AFA-Voz Scale)

Obtaining evidence of content-based validity of the Self-Perceived Acute Voice Fatigue Scale (AFA-Voz Scale).

This study followed the Standards for Educational and Psychological Testing (SEPT) guidelines for test validation and was conducted in two stages. First, the content was developed based on the analysis of two systematic reviews with high quality evidence to identify the main aspects to be assessed in acute vocal fatigue. Then, a committee of five voice experts - all with more than ten years of clinical and scientific experience - was formed to assess the relevance of the selected items, using a Likert-type scale in an online form. Overall content validity indexes (CVI) and item validity indexes (CVI-I) were calculated to assess the relevance of the items.

The data indicated that the clinical presentation of acute vocal fatigue can be assessed in three dimensions: the level of self-reported fatigue, physical discomfort, and restriction in voice use. These items were included in the scale, which also included an anamnesis section to characterize the patient and their vocal demands. In the first round of evaluation, a CVI of 0.96 was obtained, with CVI-I ranging from 0.8 to 1.0. After suggested adjustments, the second round presented CVI and CVI-I equal to 1.00.

The items of the AFA-Voz Scale were considered excellent regarding their relevance for the evaluation of acute vocal fatigue. The scale has high potential for clinical use and in future research on the subject.