Table 2. Table 2 shows the results of the Friedman test performed to compare the reduction in VAS scores for loudness, annoyance and quality of life parameters for the three groups across different time points of treatment.

	VAS-Loudness		VAS-Annoyance		VAS-Quality of Life
	Chi-Square (χ2)	p	Chi-Square (χ2)	p	Chi-Square (χ2)	p
Delta	23.52	< 0.001	34.27	< 0.001	31.68	< 0.001
Alpha	24.98	< 0.001	27.06	< 0.001	31.08	< 0.001
White noise	21.66	< 0.001	26.32	< 0.001	4.93	0.09