TABLE 3.

Association Between Self-Reported Hearing-Related Symptoms and Estimated Exposure to Music at Potentially Hazardous Levels Among Adolescents Aged 12 to 19 Years (N = 1512), by Source of Music: The Netherlands, 2007

	Hearing-Related Symptoms at Least Once in the Prior Month After Listening to Music Through Earphonesab		Hearing-Related Symptoms at Least Once in the Prior Year After Attending a Discothequec
	%	OR (95% CI)	%	OR (95% CI)
Total study population	30.0		61.2
Equivalent sound level for 56 h/wk, dBA
< 80 (Ref)	24.5	1.00	47.7	1.00
80–84.99	34.4	1.60 (1.05, 2.41)	87.4	8.21 (5.66, 11.90)
85–89.99	37.1	1.78 (1.20, 2.66)	80.0	4.53 (2.77, 7.40)
≥ 90	45.2	2.42 (1.79, 3.29)	70.0	3.30 (1.66, 6.56)

Note. CI = confidence interval; dBA = decibels; OR = odds ratio. Current EU safety standards specify that music volume levels of at least 80 dBA for 40 hours per week are potentially damaging. However, a report of the EU's Scientific Committee on Emerging and Newly Identified Health Risks asserts that listening to a sound level of more than 89 dBA for 1 hour per day (i.e., 7 hours per week) is potentially damaging. The noise exposure of listening to 89 dBA for 7 hours per week is equal to that of listening to 80 dBA for 56 hours per week. Thus, we used a loosened minimum safety standard of 80 dBA for 56 hours per week, to account for weekend listening. Associations were calculated as multilevel multivariate ORs that accounted for clustering within school classes and that were controlled for age, gender, school type, and ethnicity.

^aMusic from MP3 players and nonportable music players (home stereos) combined.

^bThe sample size was n = 1502 because 10 participants had missing data on items necessary for the analysis (exposure time, age, ethnicity, or experience of hearing-related symptoms).

^cThe sample size was n = 1427 because 85 participants had missing data on items necessary for the analysis (exposure time, age, ethnicity, or experience of hearing-related symptoms).