Clinical experience and categorical perception of children's speech.

More-experienced SLPs/SLTs are less likely to use the entire range of continuous rating scales to rate children's speech accuracy than less-experienced SLPs/SLTs or clinically untrained listeners. Implications for service delivery are discussed. What this paper adds What is already known on the subject Children's productions of individual sounds, like /k/, become gradually more adult-like over the course of development. For a child who has a [t] for /k/ error, this gradual development means that children's productions become progressively less like /t/ and more like /k/ over development. Phonetic transcription does not capture this gradual development. In contrast, studies have shown that continuous ratings of children's speech (such as rating productions on a scale anchored by the text "the 't' sound" at one end and "the 'k' sound" at the other end) can capture this gradual development. What this paper adds to existing knowledge To determine continuous ratings are clinically feasible, we must first determine whether clinical experience affects people's use of continuous rating scales to rate children's speech. We conducted an on-line speech perception experiment in which 81 speech-language pathologists/speech and language therapists (SLPs/SLTs) and 20 non-SLPs/SLTs rated 60 productions by children on continuous rating scales. The 60 stimuli included many sounds that had been independently verified to be intermediate productions (i.e., a target /k/ that was neither completely /k/-like nor completely /t/-like). Non-SLPs/SLTs and less-experienced SLPs/SLTs rated those intermediate sounds with intermediate ratings (i.e., somewhere on the midpoint of a continuous scale). In contrast, more-experienced SLPs/SLTs were more likely to rate those sounds as instances of endpoints (i.e., as either /k/ or /t/). What are the potential or actual clinical implications of this work? This finding suggests that clinical experience is paradoxically associated with a reduced tendency to use the entire range of responses on continuous rating scales. This finding suggests that we must better understand the cause of this reduced tendency, so that clinicians at all levels can use continuous rating scales equally effectively.