CPAP was so effective that it replaced surgery as the first line ( it became the "gold standard") treatment for OSA. Since its invention, there have been variations on UPPP using laser and ablation, which have had varying levels of success. Also introduced were other types of surgical interventions that are intended to manage the tongue.
Also developed with the intent of managing the tongue and enlarging the opening to the upper airway through moving the jaw forward are oral appliances - tongue retaining devices and mandibular advancement devices.
There are also more radical surgical procedures... breaking and moving the jaw forward and bariatric surgery.
Finally there are new therapies now the horizon such as Provent and Aura6000.
How do we establish the relative merits of these various therapies? What does it mean that they "work"? Is it the elimination of snoring and/or reduction of Apnea-Hypopnea Index and/or lowering blood pressure and/or reduced insulin resistance and/or improved psychomotor vigilance and/or improved cognitive functioning? Are we missing something if we stop at saying - four hours per night for 70% of the nights over a 30 day period.
It is difficult to measure quality in healthcare with respect to OSA if the benchmarks themselves vary from person to person.
It may be that the science of treating sleep apnea is still too young to have a specific number similar to diabetes, where if your HA1C is above or below a certain point there is a problem.
Today, I don't offer any answers. Today I only ponder.