Table 1 Summary of studies included in the meta-analysis

Brehmer et al. [11]

31

Positive reaction to a minimum of two of four diagnostic tests:

(1) Application of dilatative nasal strips like breath right

(2) Modified Cottle test using a Q-tip

(3) Use of nasal stents

(4) Cottle test

Before treatment vs after treatment

NOSE

SNOT 20

Mean snoring intensity (dB)

Snore Outcomes survey

EuroQoL group questionnaire for generic quality of life

AHI

Percent of sleeping time spent with a snoring intensity > 45 dB

Baseline: 65 ± 14.81

3-month: 30 ± 18.52

Jacobowitz et al. [12]

50

Positive symptomatic improvement with use of external or internal nasal dilators, Q-Tip or curette test (manual intranasal lateralization), or the Cottle Maneuver (manual lateral retraction of the cheek)

Before treatment vs after treatment

NOSE

Satisfaction survey

Baseline: 79.9 ± 10.8

3-month: 27.3 ± 18

6-month: 24.7 20.4

Wu et al. [15]

20

Positive response to one of the following temporary measures: Breathe; Right Strips; Nasal stents; or modified Cottle maneuver

Before treatment vs after treatment

SNOT 22

NOSE

VAS

Volume of frontal 1/3 of nasal cavity (cm³)

Peak heat flux posterior to vestibule

Baseline: 78.89 ± 11.57

3-month: 31.39 ± 18.30

Silvers et al. [14]

117 (active group: 77; control group: 40)

Positive response to a temporary nasal dilation measure (modified Cottle maneuver)

Before treatment vs after treatment

Active group vs control group

NOSE

Ease-of-breathing VAS score

Active group:

baseline: 76.7 ± 12.6

3-months: 34.4 ± 24.85

Control group:

baseline: 78.7 ± 14.3

3-months: 62.0 ± 29.04

Yao et al. [16]

119

Positive response to modified Cottle maneuver or other temporary nasal valve dilation or stabilizing measures

Before treatment vs after treatment

NOSE

Satisfaction survey

Baseline: 80.3 ± 12.6

3-month: 32.9 ± 24.2