Original article

Scand J Work Environ Health 2010;36(3):242-249    pdf


Modeling the Unites States government’s economic cost of noise-induced hearing loss for a military population

by Tufts JB, Weathersby PK, Rodriguez FA

Objective The purpose of this paper is to demonstrate the feasibility and utility of developing economic cost models for noise-induced hearing loss (NIHL). First, we outline an economic model of NIHL for a population of US Navy sailors with an “industrial”-type noise exposure. Next, we describe the effect on NIHL-related cost of varying the two central model inputs – the noise-exposure level and the duration of exposure. Such an analysis can help prioritize promising areas, to which limited resources to reduce NIHL-related costs should be devoted.

Methods NIHL-related costs borne by the US government were computed on a yearly basis using a finite element approach that took into account varying levels of susceptibility to NIHL. Predicted hearing thresholds for the population were computed with ANSI S3.44–1996 and then used as the basis for the calculation of NIHL-related costs. Annual and cumulative costs were tracked. Noise-exposure level and duration were systematically varied to determine their effects on the expected lifetime NIHL-related cost of a specific US Navy sailor population.

Results Our nominal noise-exposure case [93 dB(A) for six years] yielded a total expected lifetime cost of US$13 472 per sailor, with plausible lower and upper bounds of US$2500 and US$26 000. Starting with the nominal case, a decrease of 50% in exposure level or duration would yield cost savings of approximately 23% and 19%, respectively. We concluded that a reduction in noise level would be more somewhat more cost-effective than the same percentage reduction in years of exposure.

Conclusion Our economic cost model can be used to estimate the changes in NIHL-related costs that would result from changes in noise-exposure level and/or duration for a single military population. Although the model is limited at present, suggestions are provided for adapting it to civilian populations.