No, only parents who have attended some clinic visits should give the verbal contingencies. To ensure that the Lidcombe Program works properly, the speech-language pathologist needs to train every parent who will give verbal contingencies.
It is the responsibility of the speech-language pathologist to train the parents or carers to deliver treatment safely and effectively. For this reason, it is typical that the only parent to deliver treatment at home is a parent who attends the clinic. The speech-language pathologist specifically trains the parent and assesses their skills to maximise treatment impact and minimise risk to the child. If both parents attend the clinic session and are trained to deliver the treatment effectively and safely then it may be beneficial to involve them both. Care must be taken to ensure that the parents are clear about their roles in treatment and communicate with each other to ensure optimal treatment dosage.
The speech-language pathologist must carefully consider the benefits and potential risks for the child prior to involving a parent or carer who cannot regularly attend the clinic.