Data Items and Collection Process
Information obtained from each article pertaining to the primary
outcomes of interest included authors, year of publication, number of
study participants, mean age, BMI, pre- and post-op AHI and LSAT (Table
1). BMI was documented in terms of either kg/m2,
percentile, or Z-score across all studies; for consistency, we converted
BMI units to either “normal,” “overweight,” or “obese.” Normal BMI
is defined as BMI < 85 percentile for age or a Z-score
< 1, overweight is defined as BMI between 85 and 95 percentile
for age or a Z-score between 1 and 2, and obese is defined as BMI
> 95 percentile for age or a Z-score >
2.9 For studies which included a variety of single or
multi-level surgical sites (e.g., lingual tonsillectomy alone, or
revision adenoidectomy plus turbinoplasty), only outcome measures that
involved tongue surgery were extracted for review. These measures were
primarily from PSG data including mean AHI change or LSAT change after
surgery (primary outcome), and the percentage of subjects who were
successfully treated by surgery (responders, secondary outcome). The
definition of a responder in this study depends on preoperative AHI. If
the preoperative AHI > 5 events/hr then response was
defined as post-operative AHI < 5 and/or a 50% reduction in
AHI. Patients with a preoperative AHI of < 5 were considered
responders if postoperative AHI was <1 which is considered
surgical cure. This definition was adapted from the definition used by
He et al.15