Use of historical data and a novel metric in the evaluation of the effectiveness of hearing conservation program components. Efficacy of enforcement in an industrial hearing conservation program. Hearing conservation programs (HCPs): the effectiveness of one company's HCP in a 12-hr work shift environment. Effectiveness of a tailored intervention to increase factory workers' use of hearing protection. Effectiveness of an intervention to increase construction workers' use of hearing protection. The effectiveness of hearing protective devices. Use of comparison populations for evaluating the effectiveness of hearing loss prevention programs. A hearing conservation program for Wisconsin youth working in agriculture. Efficacy of a computer-based hearing test and tailored hearing protection intervention.
To evaluate the effectiveness of hearing conservation programs (HCP) and their specific components in reducing noise-induced hearing loss (NIHL).
                This retrospective cohort study was conducted at one food-processing plant and two automotive plants. Audiometric and work-history databases were combined with historical noise monitoring data to develop a time-dependent exposure matrix for each plant. Historical changes in production and HCP implementation were collected from company records, employee interviews and focus groups. These data were used to develop time-dependent quality assessments for various HCP components. 5478 male (30,427 observations) and 1005 female (5816 observations) subjects were included in the analysis.
                Analyses were conducted separately for males and females. Females tended to have less NIHL at given exposure levels than males. Duration of noise exposure stratified by intensity (dBA) was a better predictor of NIHL than the standard equivalent continuous noise level (L(eq)) based upon a 3-dBA exchange. Within this cohort, efficient dBA strata for males were <95 versus ≥ 95, and for females <90 versus ≥ 90. The reported enforced use of hearing protection devices (HPDs) significantly reduced NIHL. The data did not have sufficient within-plant variation to determine the effectiveness of noise monitoring or worker training. An association between increased audiometric testing and NIHL was believed to be an artifact of increased participation in screening.
                Historical audiometric data combined with noise monitoring data can be used to better understand the effectiveness of HCPs. Regular collection and maintenance of quality data should be encouraged and used to monitor the effectiveness of these interventions. Relative efficacy of various levels of enforcement in the use of personal hearing protective devices was investigated among employees of a large industrial plant. The main variable was that each of four groups of employees worked during a different period of enforcement policy on the use of personal hearing protection. Analysis of variance of mean hearing levels using three different audiometric grading schemes with different levels of sensitivity, namely, the 0.5, 1, 2 kHz Hearing Level Index, the 1, 2, 3 kHz Hearing Level Index, and the 4000 Hz single puretone test indicate that the enforcement policy did have a dramatic effect on the efficacy of the hearing conservation program and should give similar results in other industrial settings. When and where the use of personal hearing protection was left to the employee it was found that hearing loss among the noise-exposed was very much in excess of that among a non-noise-exposed group. Mandatory use of personal protective devices was found to be much more effective in conserving hearing that the voluntary approach. Mandatory use of earmuffs exclusively proved to be less effective than mandatory use of personal hearing protection when the employee was given a choice of earmuffs or earplugs. Enactment of the Occupational Safety and Health Act did not result in greater hearing conservation over the existing company mandatory hearing conservation program which is quite effective. An existing hearing conservation program (HCP), originally designed when an 8-hr work shift schedule was in effect, was evaluated at a plant site where a 12-hr work shift schedule is now utilized. The study included the following phases: a noise analysis of the work environment, HCP evaluation through the use of audiometric data base analysis (ADBA), applying ADBA procedures and a comparison of the shift in hearing threshold levels (HTLs) for the 8-hr and 12-hr work shifts, and an evaluation of the hearing protection devices (HPDs) being used at the facility over the 12-hr work shift by measuring temporary threshold shift (TTS). The mean measured employee time-weighted average (TWA) in the process area where the TTS study was conducted was 92 dBA. It was found that the existing HCP is at best marginal. The most likely causes of this less-than-desirable rating are inadequate audiometric testing procedures and inadequate HPD utilization. Furthermore, it was concluded that, at this time, the introduction of the 12-hr work shift has had no impact on the level of effectiveness of the HCP. In evaluating the three HPDs in use at the facility (3-M foam earplug, E-A-R foam earplug, and Bilsom Soft earplug), it was found that they all offered effective protection from noise at all audiometric test frequencies (0.5 to 6 kHz) except 0.5 kHz. All three HPDs exhibited TTS at 0.5 kHz with the TTS measured significant at the p less than 0.05 level for the E-A-R and 3-M wearer groups. In the United States it is estimated that more than 30 million workers are exposed to harmful levels of noise on the job. When engineering or administrative controls cannot be used to reduce noise, workers should always use hearing protection devices (HPDs) when exposed to loud noise to prevent noise-induced hearing loss (NIHL). Previous research has shown that workers do not always use HPDs when required; therefore, it is essential that workers assume personal responsibility for preventing NIHL by increasing their use of HPDs.
                This study tested the effectiveness of an individually tailored multimedia intervention to increase use of HPDs by factory workers.
                A randomized controlled design was used to compare the effects of a tailored intervention (n= 446) with two other interventions (a nontailored predictor-based intervention (n= 447) and a control intervention (n= 432)) on workers' self-reported use of HPDs 6 to 18 months following the intervention.
                Only those workers receiving the tailored intervention significantly increased their use of HPDs from pretest to posttest. However, this increase significantly differed from the nontailored group but not from the control group.
                Individually-tailored interventions offer promise for changing behavior. In light of the similarity between the results for the tailored intervention and the control intervention groups, further research is needed to understand barriers to HPD use and how to maximize the benefits of individually tailored interventions in this setting. In this project we tested the effectiveness of a theory-based intervention (video, pamphlets, and guided practice session) to increase the use of hearing protection devices (HPDs) among Midwestern construction workers and a national group of plumber/pipefitter trainers. Posttest measures were collected 10-12 months following this intervention. Pender's Health Promotion Model (1987) provided the conceptual basis for development of the training program. A total of 837 high-noise-exposed workers were included in the analysis: 652 regional Midwestern construction workers and 185 national plumber/pipefitter trainers. Effectiveness of the intervention was determined through the sequence of analyses recommended by Braver and Braver (1988) for the Solomon Four-Group Design. Analysis of variance and covariance of postintervention use and intention to use HPDs and a meta-analytic test were done. These analyses indicated that the intervention significantly increased use of HPDs but had no effect on intention to use HPDs in the future. Pretesting had no effect on use. Actual or potential applications of this research include guidance in the development of successful theory-based interventions to increase use of HPDs. The effectiveness of a hearing conservation program, and specifically the effectiveness of hearing protection devices (muffs in this case), was investigated over a five-year period, since the inception of the program at a major plant of the Ingersoll-Rand Company. The study concentrated on three groups (Class I, II, and III) of 213 employees whose noise level exposure did not change during the five-year study period. A hearing conservation criterion of 90dBA was utilized. One group consisted of office workers in which the level was well below this, a second group from a machine shop in which the level was slightly below the criterion, and a third group from foundry areas in which the levels were considerably above the 90dBA level. Personal ear protection was worn during the study period only by the last group. The mean differences in hearing levels were insignificant and were essentially the same in the three groups, at each frequency, and regardless of the baseline hearing thresholds. It is apparent that there were no significant changes in hearing threshodls during the study period among a non-noise exposed group; a mild to moderate noise-exposed group; and a group exposed to high levels of steady state noise, but wearing ear protectors. These results indicate that a hearing conservation program which includes audiometric testing and personal ear protection, utilizing a hearing conservation criterion of approximately 90dBA, does adequately protect the hearing of noise-exposed workers. One approach for evaluating the effectiveness of Hearing loss prevention programs (HLPPs) is to compare the rate of hearing loss in a study population with that in a reference population. This approach was used to evaluate the HLPP of a population of 14,900 employees of an industrial company with branches across the United States. Three reference populations were selected from a database of 22 industrial companies compiled under the sponsorship of the National Institute for Occupational Safety and Health. The risk of hearing loss in the study population was estimated relative to each of the three reference populations using the Cox proportional hazards model after adjustment for race, age at baseline, and hearing threshold at time of enrollment in the HLPP. In comparison with the three reference populations, hearing loss was 2.1 to 3.9 times more likely to occur in study population males and 1.8 to 5.1 times more likely in study population females. The 95% confidence interval around each risk estimate precluded unity, indicating that each risk estimate was statistically significant. These results indicate that the performance of the subject HLPP needs improvement. This study demonstrated the use of comparison populations for evaluating the effectiveness of HLPPs. Adolescents working in agricultural settings may be exposed to noise levels that result in hearing loss. The article describes the design, implementation, and results of a four-year, hearing conservation program (HCP) conducted at school. Thirty-four schools (753 students) were randomly assigned to either an intervention or control group. The intervention included multicomponent educational strategies and employed features of an industrial HCP. Final compliance surveys indicated 87.5% of intervention students reported using hearing protection devices (HPD) at least some of the time, compared to 45% of control students. The HCP components with the greatest reported influence were distribution of HPDs for use on the farm and yearly hearing tests. Eighty percent of intervention students reported intention to use HPDs in the future. It is feasible to conduct a hearing conservation program with junior high school and senior high school students, and it appears possible to persuade teen-agers to protect themselves from exposure to loud noise while working on a farm. Advances in computer technology and accessibility enable researchers to provide individually tailored interventions for behavioral change. Using multimedia technology, this study developed and tested a computer-based hearing test and a tailored intervention. The purpose of this study was to evaluate, using a randomized experimental design, the efficacy of the intervention to increase workers' use of hearing protection. The tailored intervention developed by the research team showed more significant short-term effect measured immediately after the intervention than the control intervention. For the long-term effect measured 1 year after the intervention, both tailored and control groups showed significant increase in their reported use (7% vs. 6%) from preintervention to postintervention, but no significant difference between the two groups. The change accomplished in this study was small progress toward the desired level of 100% use of hearing protection to prevent noise-induced hearing loss. This finding showed that changing workers' hearing protection behavior is difficult.
There is low quality evidence that implementation of stricter legislation can reduce noise levels in workplaces. Even though case studies show that substantial reductions in noise levels in the workplace can be achieved, there are no controlled studies of the effectiveness of such measures. The effectiveness of hearing protection devices depends on training and their proper use. There is very low quality evidence that the better use of hearing protection devices as part of HLPPs reduces the risk of hearing loss, whereas for other programme components of HLPPs we did not find such an effect. Better implementation and reinforcement of HLPPs is needed. Better evaluations of technical interventions and long-term effects are needed.