I don't have personal experience with Lidcombe, but I'd be a little skeptical: - It's very well researched compared to other programs (not saying much when it comes to fluency treatment, but still). But the BIG caveat on that is that it's mostly research conducted and funded by Lidcombe. So do with that what you will. - It focuses on modeling and "indirect" treatment, i.e. creating low-stress speaking situations and passively demonstrating techniques rather than directly teaching techniques to deal with disfluency/blocks when they happen. Which jives with your research suggesting that it's less effective after ~6 years. - It's certainly popular (particularly in Australia, apparently?), but not your only option but any means for school-aged kids. Those options really depend on your country and situation - just remember that a lot of therapists have minimal fluency experience/knowledge, so be picky (https://www.stutteringhelp.org/ is a good place to start, or https://www.friendswhostutter.org/ if you happen to be in the US). And you're right on with the genetic component - that's one of the constants that consistently shows up in research. A father who stutters is very likely to pass it to their daughter, and about half as likely to pass it to their son (so probably associated with the X chromosome) (Source: SO is an SLP that learned about Lidcombe in school, although emphasizes that they don't specialize in fluency)