In this study, the authors examined whether a visual analog scale (VAS; as below, but with speech sounds) can be used to perceptually characterize speech variability within phonetic categories. A group of adults (not SLPs) listened to /s/ and /θ/ syllables extracted from words produced by 2–5-year-old children. Their task was to place the sounds on a continuum from /s/ vs. /θ/. The scale was found to be quite useful, in that its measures correlated “…with a variety of continuous measures of children’s production…”…