Comparison 3. Improvement (tympanogram or composite).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Improvement composite: 1 month or less	6		Relative Risk (Random, 95% CI)	1.89 [0.83, 4.31]
2 Improvement composite: > 1 month	6		Relative Risk (Random, 95% CI)	1.74 [1.22, 2.50]
3 Improvement composite by intervention: 1 month or less	6		Risk Ratio (Random, 95% CI)	1.89 [0.83, 4.31]
3.1 Intervention A ‐ classic Otovent or carnival blower + balloon	5		Risk Ratio (Random, 95% CI)	1.47 [0.69, 3.13]
3.2 Intervention C ‐ Politzer	1		Risk Ratio (Random, 95% CI)	7.07 [3.70, 13.51]
4 Improvement composite by intervention: > 1 month	6		Risk Ratio (Random, 95% CI)	1.74 [1.22, 2.50]
4.1 Intervention A ‐ classic Otovent or carnival blower + balloon	4		Risk Ratio (Random, 95% CI)	1.22 [1.00, 1.49]
4.2 Intervention C ‐ Politzer	2		Risk Ratio (Random, 95% CI)	2.25 [1.67, 3.04]