What is RESTART-DCM and the Demands and Capacities Model?

Published by Unseen Progress, an independent publisher of caregiver research. Last reviewed 2026-05-10. Part of the childhood stuttering research overview.

Short answer. RESTART-DCM is an indirect, parent-mediated treatment for preschool stuttering developed in the Netherlands and grounded in the Demands and Capacities Model (DCM). The DCM frames stuttering as the child's speech-language capacities being temporarily exceeded by the demands placed on them — by the environment, by the listener, and by the child's own internal pressure. RESTART-DCM treats stuttering by adjusting the demands rather than by directly targeting the disfluency. It is one of the three preschool stuttering treatments with a meaningful evidence base, alongside the Lidcombe Program and Palin PCI.

The Demands and Capacities Model

The Demands and Capacities Model, developed by Starkweather and Gottwald in the 1980s and elaborated since, proposes that fluent speech requires the child's capacities (motor speech skills, language formulation, cognitive resources, emotional regulation) to keep pace with the demands placed on them in the moment (Starkweather, 1987). When demands exceed capacities, the speech system produces disfluencies — repetitions, prolongations, and blocks. When capacities catch up, or when demands drop, fluency returns.

The DCM is a frame, not a single treatment. It explains why stuttering fluctuates moment-to-moment: a tired child at a noisy birthday party with multiple adults firing questions has high demand and reduced capacity. The same child the next morning, rested and in a quiet one-on-one conversation, has lower demand and full capacity. Disfluency rises and falls accordingly.

Two clinical implications follow. First, changing the demand side can produce immediate fluency improvements even before any change in the child's underlying capacities. Second, a child whose capacities are still developing will benefit most from environmental adjustments that reduce demand during that window.

What RESTART-DCM treatment looks like

RESTART-DCM is the structured Dutch protocol that operationalises the DCM into a parent-mediated indirect treatment for preschool stuttering. The treatment is delivered by the parent, supervised by an SLP, and works through systematic adjustments to the communicative environment (Franken et al., 2005; Franken & Putker-de Bruijn, 2007).

The core moves include:

  • Slowing the parent's rate of speech. Children mirror the conversational pace of the adult speaking to them; reducing parent speaking rate by approximately 20% lowers the time-pressure demand on the child.
  • Lengthening pauses between turns. A 1–2 second pause before the parent responds gives the child more time to formulate without competing for the floor.
  • Reducing question density. Shifting from rapid-fire questions to comments and acknowledgements reduces formulation demand on the child.
  • Holding eye contact and an accepting expression during disfluency. This signals that the child's communication is worth waiting for.
  • Calibrating language complexity to the child. Avoiding language that is several developmental steps ahead of where the child is.
  • Reducing overlap and interruption. Whole-family conversational rules — taking turns, not interrupting — reduce the volume of turn-taking pressure on the child.

A parent does not implement all of these at once. The SLP works through them systematically, adjusting one or two demand variables at a time and observing the child's response.

What the evidence shows

Marie-Christine Franken and colleagues' randomised comparison trial of RESTART-DCM versus the Lidcombe Program in Dutch preschoolers found that both treatments produced significant and comparable reductions in stuttering at follow-up, with no clear superiority for either approach (Franken et al., 2005; de Sonneville-Koedoot et al., 2015). This is one of the most-cited findings in contemporary preschool stuttering research, because it suggests that indirect demand-reduction approaches can be as effective as direct contingency-based approaches in the right hands and the right child.

The evidence base for RESTART-DCM is smaller than for Lidcombe but is methodologically strong and has been replicated. Clinical guidelines in the Netherlands and parts of Europe favour indirect approaches as a first-line treatment for younger preschoolers; clinical guidelines in Australia and parts of the English-speaking world favour Lidcombe. Both choices are evidence-supportable.

When an indirect approach may be preferred

The choice between RESTART-DCM (indirect) and Lidcombe (direct) is made by the SLP based on the child's profile. Indirect approaches are often preferred when:

  • The child is young (3–4) and may not tolerate direct contingencies well
  • The child has heightened awareness or sensitivity around their stuttering, where direct attention to fluency risks increasing speech anxiety
  • The communicative environment at home has identifiable demand factors that are amenable to change (rapid pace, frequent interruption, high question density)
  • The parent prefers a non-corrective approach
  • The clinical assessment identifies specific capacity-demand mismatches

Lidcombe is often preferred when the child is robust to direct contingencies, when the family is well-suited to the structured daily session format, and when the SLP has Lidcombe expertise.

What does not work

  • Treating DCM as a single intervention. The model is a frame; specific demand-reduction moves vary by child. A parent who slows their speech but ignores other demands is not implementing the protocol.
  • Demand-reduction without SLP supervision. As with Lidcombe, the program requires clinical calibration. Parents implementing demand reduction unsupervised often miss which demand variable is most relevant for their specific child.
  • Switching back and forth between RESTART-DCM and Lidcombe mid-treatment. The protocols are coherent treatment systems and are not designed to be alternated. The SLP picks one based on assessment and stays with it for the trial period.

Related questions

References

  • Starkweather, C. W. (1987). Fluency and Stuttering. Prentice-Hall.
  • Franken, M.-C., Kielstra-Van der Schalk, C. J., & Boelens, H. (2005). Experimental treatment of early stuttering: A preliminary study. Journal of Fluency Disorders, 30(3), 189–199.
  • de Sonneville-Koedoot, C., Stolk, E., Rietveld, T., & Franken, M.-C. (2015). Direct versus indirect treatment for preschool children who stutter: The RESTART randomized trial. PLOS ONE, 10(7), e0133758.
  • Onslow, M., Packman, A., & Harrison, E. (2003). The Lidcombe Program of Early Stuttering Intervention. Pro-Ed.
  • Stuttering Foundation of America. www.stutteringhelp.org
  • American Speech-Language-Hearing Association. Childhood Fluency Disorders Practice Portal.

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