Oral appliance therapy was not associated with improvements in daytime sleepiness from baseline to @-month follow-up when compared with the placebo device ; Epworth score > @ : @ % at baseline to @ % at follow-up for the oral appliance group vs @ % at baseline to @ % at follow-up for the placebo device group , P = @ ; median ( IQR ) for Karolinska score @/wk : @ ( @ to @ ) at baseline to @ ( @ to @ ) at follow-up for the oral appliance group vs @ ( @ to @ ) at baseline to @ ( @ to @ ) at follow-up for the placebo device group , P = @ ; mean between-group difference in OSLER test , -@ min ( @ % CI , -@ to @ ) .