Evidence from animal studies has shown that noise exposure may exacerbate age-related hearing threshold loss. In humans, studies have tended to investigate the effects of noise exposure and ageing on hearing thresholds in isolation and have shown that both factors are associated with higher (worse) hearing thresholds in the standard and/or extended high-frequency audiometric ranges. Moreover, both noise exposure and ageing are associated with higher (worse) speech-perception-in-noise thresholds. Occupational noise exposure is a major public uncontrolled public health issue in Palestine. Moreover, many people with age-related and/or noise-induced hearing problems lack a formal diagnosis. The current study primarily investigates the effects of lifetime noise exposure and the interaction of ageing and noise exposure in Palestinian workers on (1) standard pure-tone audiometric thresholds, (2) extended high-frequency audiometric thresholds, and (3) speech-perception-in-noise thresholds. Secondary outcome measures include tinnitus and binaural unmasking of speech stimuli in noise.
