Published by Unseen Progress, an independent publisher of caregiver research. Last reviewed 2026-05-10. Part of the childhood stuttering research overview.
Short answer. The Lidcombe Program is a behavioural treatment for preschool stuttering in which a parent, trained and supervised weekly by a speech-language pathologist, delivers brief verbal contingencies during a structured daily conversation and rates the child's daily stuttering severity on a 1–10 scale. The randomised-trial evidence base — established by Mark Onslow, Ann Packman, Elisabeth Harrison and colleagues at the Australian Stuttering Research Centre — makes it the best-evidenced treatment for preschool stuttering currently available (Onslow, Packman & Harrison, 2003).
A Lidcombe session is short, structured, and time-boxed — typically 10–15 minutes in Stage 1, when the child is being treated to natural fluency, and shorter and less frequent in Stage 2, when fluency is being maintained. The parent and child engage in a planned, low-demand conversation: looking at a picture book, playing with a toy, describing a routine, talking through a craft activity. The child speaks; the parent listens.
Inside that conversation, the parent delivers two kinds of brief verbal contingencies:
For periods of stutter-free speech — the dominant contingency type — the parent provides a brief acknowledgement, request for self-evaluation, or praise. Examples used in the protocol: "That was smooth talking." "No bumps that time." "Was that smooth?" (eliciting child agreement).
For unambiguous moments of stuttering — used much less frequently, and always gently — the parent acknowledges the stutter or asks the child to try again. Examples: "That was a bit bumpy." "Can you say that again smoothly?"
The ratio of stutter-free contingencies to stuttering contingencies is heavily weighted toward stutter-free; the protocol is calibrated to avoid making the child feel corrected.
Outside the session, the parent rates the child's overall stuttering severity for that day on a 1–10 scale, where 1 = no stuttering and 10 = extremely severe stuttering. The rating is taken to the weekly SLP appointment, where parent and clinician compare it to the SLP's own measure of stuttered syllables per minute and adjust the program accordingly (Onslow, Packman & Harrison, 2003).
The severity rating is not optional. It is the instrument that lets the SLP tell whether the program is working, whether the contingency ratio needs adjusting, whether the session length needs changing, and when the child is ready to move from Stage 1 to Stage 2. Without it, the program is operating without its feedback loop.
Onslow and colleagues' randomised controlled trials, including the New Zealand–Australian replication trial reported in the British Medical Journal, established that preschool children receiving Lidcombe treatment show clinically and statistically significant reductions in stuttering compared to no-treatment controls (Jones et al., 2005). Effect sizes are large; a substantial proportion of children reach near-zero stuttering, maintained at follow-up. The evidence is strong enough that the Lidcombe Program is the most-recommended direct treatment for preschool stuttering in clinical guidelines worldwide.
Two important nuances:
Parents commonly report two friction points. First, the structured session can feel unnatural — sitting with a picture book and consciously delivering verbal contingencies is not how families normally talk. Second, the severity rating can feel clinical — turning a child's communication into a daily 1–10 score is uncomfortable for some parents. Both reactions are common and expected. The session is a contained 10–15 minute window inside an otherwise normal day; outside it, family conversation is normal warm conversation, with no contingencies and no rating going on.
Parents who experience the program as eroding the relationship usually benefit from a check-in with the SLP. Session length, contingency balance, child mood, and even the choice of activity all get calibrated weekly. The program is designed to be collaboratively delivered, not executed unsupervised by the parent alone (Onslow, Packman & Harrison, 2003).
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