Rabinowitz 2011.

Methods	CBA study/ITS (authors provided additional data for ITS analysis)
Participants	Various workers of an aluminium smelter n = 312
Interventions	Intervention: daily monitoring of at‐ear noise exposure and regular feedback from supervisors Control: ongoing hearing conservation programme (regulation‐mandated hearing tests, noise measurements, training)
Outcomes	Median TWA ambient noise exposures Median and range of noise exposures inside hearing protection (intervention group) High frequency hearing threshold levels (2, 3, 4 kHz) Annual rate of hearing loss (dB/year)
Notes	Long‐term Comparability ‐ intervention/control (matched on age, gender and hearing): age: similar age (within 5 years); intervention mean 48.7 years, control mean 48,6 years hearing: controls matched (control group 1) and highly matched (control group 2): Control group 1: baseline hearing = similar high frequency hearing threshold levels (binaural average of 2, 3 and 4 kHz) (within 5 dB) (intervention, n = I 78; control n = 234) Control group 2: baseline hearing and initial rate of hearing loss during pre‐intervention period (intervention, n = 46; control, n = 138) For risk of bias see Table 20