A Pilot Study to Prevent Hearing Loss in Farmers

Hearing Difficulties Among Farmworkers in the México-US Southwest Border Region

Migrant and seasonal farmworkers are a vulnerable population with a potentially high risk for hearing loss due to farm-related noise exposures. Occupational noise-induced hearing loss (NIHL) is permanent, and it is associated with an increased risk for injuries on the job, as well as communication difficulties, isolation, and depression. The México/US border region is one of the most productive agricultural regions in the country, however, no known studies have explored hearing loss among farmworkers in this area. This pilot study was a first step toward measuring and addressing hearing loss and noise exposure among this region's farmworkers. We conducted a cross-sectional survey to estimate the prevalence of subjective hearing difficulties among Yuma County, Arizona farmworkers. Survey interviews took place during a late-night farmworker health fair from 2 am to 6 am to accommodate local farms' labor schedules. Multivariable regression adjusted for demographic and work covariates estimated subjective hearing loss prevalence ratios. Among 132 farmworker participants, 36% reported they have or might have hearing loss, and 62% reported no hearing loss. Subjective hearing loss prevalence was lower in farmworkers who report not working in noise compared to prevalence in farmworkers who work in noise [prevalence ratio, 0.44 (95% CI 0.23-0.82)]. This report contributes to understanding the perception of hearing-related health and occupational exposures among farmworkers in the México-US Southwest border region. The information from this line of research will inform appropriate safety measures known to lower the risk of experiencing occupational NIHL.

Effectiveness of educational programs in hearing health: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness of hearing health education programs aimed at preventing noise-induced hearing loss (NIHL), of recreational and occupational origin, by means of a systematic review and meta-analysis.

DESIGN

The search strategy was carried out in on five electronic databases, as well as referrals from experts. The risk of bias was judged, and the random effects meta-analysis was performed. The certainty of the evidence was assessed.

STUDY SAMPLE

Effectiveness studies that used educational intervention in hearing health and prevention of NIHL were included.

RESULTS

42 studies were included. The Dangerous Decibels program was the only one that could be quantitatively analysed and showed improvement in the post-intervention period of up to one week [SMD = 0.60; CI95% = 0.38-0.82; I2 = 92.5%) and after eight weeks [SMD = 0.45; CI95% = 0.26-0.63; I2 = 81.6%) compared to the baseline. The certainty of evidence was judged as very low.

CONCLUSIONS

The Dangerous Decibels program is effective after eight weeks of intervention. The other programs cannot be quantified. They still present uncertainty about their effectiveness. The level of certainty is still low for this assessment.

Design and testing of a personalized noise monitoring system

Agricultural workers are more prone to noise-induced hearing loss than are many other workers. Hearing protection device use among agricultural workers is low, but training can increase hearing protection device use. This work proposes a system designed to automatically inform agricultural workers when they were exposed to noises that exceed the National Institute for Occupational Safety and Health (NIOSH) recommended exposure level. The smartphone-based system worn on the arm uses a noise dosimeter to measure noise exposures throughout the day to within ±2 A-weighted decibels of a Class 2 sound level meter. The device collects location and audio data, which are transferred to a server and presented to the worker on a locally hosted website. The website details noise exposure and helps the worker identify where exposure occurred and what specific tasks exceed NIOSH's recommended exposure limit, putting them at higher risk of noise-induced hearing loss. With this understanding, the worker is expected to adopt behavior changes and better hearing protection use at critical places and times. This pilot study evaluates the accuracy of the noise dosimeter and GPS relative to gold-standard instruments. The system was tested on a farm with outputs compared with gold-standard instruments. A-weighted, 1-sec averaged sound pressure levels and position data were collected while users were performing a variety of tasks indoors and outdoors. The smartphone's external noise dosimeter read within ±2 A-weighted decibels of the Class 2 reference dosimeter 59% of the time. The positioning devices had an average error of sub-4 m. While not perfectly matching gold-standard instruments, the device is capable of identifying and collecting information relative to loud noise events that promote noise-induced hearing loss.

Translation, adaptation, and cross-cultural validation into Brazilian portuguese of the hearing protection assessment questionnaire (HPA)

PURPOSE

The aim of the present study is to translate, adapt, and cross-culturally validate the Brazilian Portuguese version of the questionnaire Hearing Protection Assessment Questionnaire (HPA).

METHODS

The original instrument, developed in English, seeks to assess barriers and supports related to the use of hearing protection devices (HPD), as well as workers' knowledge, habits and attitudes towards occupational noise. The translation, adaptation, and cross-cultural validation of the questionnaire consisted of five steps: Translation of the questionnaire from English to Portuguese; 2) Reverse translation from Portuguese to English; 3) Analysis of the instrument by three experts in the field; 4) Pre-test of the questionnaire with ten workers; 5) Application of the instrument to 509 workers in a meatpacking industry after the pre-employment medical exam.

RESULTS

The results indicate the construction and content validity of the Brazilian Portuguese version for use with a working population and its internal consistency.

CONCLUSION

This study resulted in the translation, cultural adaptation, and validation of the Hearing Protection Assessment Questionnaire (HPA), in order to be used to assess the use of individual hearing protection in the occupational field, called Hearing Protection Assessment Questionnaire (HPA).

Towards a Holistic Model Explaining Hearing Protection Device Use among Workers

Offering hearing protection devices (HPDs) to workers exposed to hazardous noise is a noise control strategy often used to prevent noise-induced hearing loss (NIHL). However, HPDs are used incorrectly and inconsistently, which explains their limited efficiency. Numerous models based on social cognition theories identify the significant factors associated with inconsistent HPD use and aim to improve HPD training programs and to increase HPD use. However, these models do not detail (dis)comfort aspects originating from complex interactions between characteristics of the triad “environment/person/HPD” while these aspects are known to largely influence HPD (mis)use. This paper proposes a holistic model explaining HPD (mis)use, based on the integration of a comfort model adapted to HPDs into an existing behavioral model already developed for HPDs. The model also takes into account the temporal dimension, which makes it possible to capture the scope of change in HPD-related health behaviors. This holistic description of HPD use could be used as a tool for stakeholders involved in HPD use to effectively prevent NIHL among workers.

Dementia and Cognitive Decline in Older Adulthood: Are Agricultural Workers at Greater Risk?

OBJECTIVES

To examine whether long-term exposure to agricultural work is associated with dementia prevalence and the rate of cognitive change in older adulthood.

METHOD

We employed data from the Health and Retirement Study (1998-2014). Multiple logistic regression was used to determine whether a longest-held job in the agricultural sector was associated with differences in dementia prevalence. We examined if hearing impairment, depression, and physical health indicators mediated the relationship between agricultural work and cognitive functioning. Subgroup analyses were done by age, retirement status, job tenure, and cognitive domain. We employed growth curve models to investigate implications of agricultural work on age trajectories of cognitive functioning.

RESULTS

Longest-held job in agriculture, fishing, and forestry (AFF) was associated with 46% greater odds of having dementia. The relationship between AFF exposure and cognitive functioning was not mediated by hearing impairment, depression, or physical health indicators. Results were stronger among younger and retired older adults as well as those with extensive job tenure. AFF exposure was associated with lower scores in working memory and attention and processing speed. Growth curve models indicated that while agricultural work exposure was associated with lower initial levels of cognitive functioning, over time, the pattern reversed with individuals in non-AFF jobs, showing more accelerated cognitive decline.

DISCUSSION

Consistent with European studies, results from the United States also demonstrate a higher prevalence of dementia among agricultural workers. The cognitive reserve framework may explain the seemingly paradoxical result on age patterning of cognitive performance across older adults with different work histories.

A scoping review to identify strategies that work to prevent four important occupational diseases

BACKGROUND

Despite being largely preventable, many occupational diseases continue to be highly prevalent and extremely costly. Effective strategies are required to reduce their human, economic, and social impacts.

METHODS

To better understand which approaches are most likely to lead to progress in preventing noise-related hearing loss, occupational contact dermatitis, occupational cancers, and occupational asthma, we undertook a scoping review and consulted with a number of key informants.

RESULTS

We examined a total of 404 articles and found that various types of interventions are reported to contribute to occupational disease prevention but each has its limitations and each is often insufficient on its own. Our principal findings included: legislation and regulations can be an effective means of primary prevention, but their impact depends on both the nature of the regulations and the degree of enforcement; measures across the hierarchy of controls can reduce the risk of some of these diseases and reduce exposures; monitoring, surveillance, and screening are effective prevention tools and for evaluating the impact of legislative/policy change; the effect of education and training is context-dependent and influenced by the manner of delivery; and, multifaceted interventions are often more effective than ones consisting of a single activity.

CONCLUSIONS

This scoping review identifies occupational disease prevention strategies worthy of further exploration by decisionmakers and stakeholders and of future systematic evaluation by researchers. It also identified important gaps, including a lack of studies of precarious workers and the need for more studies that rigorously evaluate the effectiveness of interventions.

Educational Interventions to Improve Safety and Health Literacy Among Agricultural Workers: A Systematic Review

Health and safety education for farmers has the potential to increase the level of health, safety literacy, and thereby improve farmers’ health and quality of life. The aim of this paper is to provide a systematic review of the published literature documenting different educational interventions for agricultural workers that have the improvement of health and/or safety literacy as an outcome. A systematic search was conducted in PubMed, Embase, Scopus and PsycINFO databases for articles focusing on educational interventions for farmers’ health and safety. From the 3357 initial hits, 36 unduplicated records met the inclusion criteria. The articles included in the review used educational interventions for farmers with the purpose of preventing farm-induced diseases and injuries, increasing the health and well-being of farmers, and promoting good manufacturing practices. The educational approaches considered varied from lectures, videos, newsletters, games, and community fairs, to involving the community in designing the intervention and training farmers to deliver the intervention to the community. Interventions that used evidence-based theories, which took into account cultural aspects and individual factors, used biomarkers as a behavior change measurement, and involved the community in the development of the intervention had the best results in terms of behavior change. The strategies of educational interventions identified in this review that produced good results have the potential to inform future researchers and policy makers in the design and implementation of public health interventions, programs and policies to improve the health of farmers and their families.

Efficacy of technology-based interventions to increase the use of hearing protections among adolescent farmworkers

OBJECTIVE

Adolescent farmworkers are exposed to loud noise during farm activities. We present a prospective study that evaluated the efficacy of low-cost, technology-based intervention approaches in high schools to enhance the use of hearing protection among adolescent farmworkers.

DESIGN

Six high schools in Iowa that agreed to participate in the study were divided into three equal groups through cluster-randomisation with each group receiving one of the three formats of hearing protection intervention: (a) classroom training, (b) classroom training coupled with smartphone app training and (c) computer training. Participants completed baseline (pre-training) and six-week post-intervention surveys for assessing hearing protection knowledge, attitudes and behaviour.

STUDY SAMPLE

Seventy participants from six schools were initially enrolled but 50 completed both pre- and post-intervention surveys.

RESULTS

In most cases, all three groups showed significant improvement in hearing protection knowledge, attitude and frequency of use from pre- to post-intervention. However, changes between groups were statistically non-significant.

CONCLUSIONS

Although all three formats led to improvements on hearing protection knowledge, attitude and behaviour, the findings of the study, perhaps due to the small sample size, did not allow us to detect whether technology-based hearing protection interventions were more effective than the traditional face-to-face training for adolescent farmworkers.

Gender differences in use of hearing protection devices among farm operators

Purpose:

Although farm operators have frequent exposure to hazardous noise and high rates of noise-induced hearing loss, they have low use of hearing protection devices (HPDs). Women represent about one-third of farm operators, and their numbers are climbing. However, among published studies examining use of HPDs in this worker group, none have examined gender-related differences. The purpose of this study was to examine gender-related differences in use of hearing protection and related predictors among farm operators.

Materials and Methods:

Data previously collected at farm shows and by telephone were analyzed using t-tests and generalized linear model with zero inflated negative binomial (ZINB) distribution.

Findings:

The difference in rate of hearing protector use between men and women farm operators was not significant. There was no difference between men and women in most hearing protector-related attitudes and beliefs.

Conclusion:

Although men and women farm operators had similar rates of use of hearing protectors when working in high-noise environments, attitudes about HPD use differed. Specifically, interpersonal role modeling was a predictor of HPD use among women, but not for men. This difference suggests that while farm operators of both genders may benefit from interventions designed to reduce barriers to HPD use (e.g., difficulty communicating with co-workers and hearing warning sounds), farm women have unique needs in relation to cognitive-perceptual factors that predict HPD use. Women farm operators may lack role models for use of HPDs (e.g., in peers and advertising), contributing to their less frequent use of protection.

Effects of interventions on use of hearing protectors among farm operators: A randomized controlled trial

OBJECTIVE

The purpose of this study was to compare the effectiveness of three interventions designed to promote hearing protector device (HPD) use.

DESIGN

Randomized controlled trial.

STUDY SAMPLE

Farm operators (n = 491) were randomly assigned to one of five intervention groups: (1) interactive web-based information with mailed assortment of HPDs; (2) Interactive web-based information only; (3) static web-based information with mailed assortment of HPDs; (4) Static web-based information only; or (5) mailed assortment of HPDs only. Data were analysed using a mixed model approach.

RESULTS

HPD use increased among all participants, and increased more among participants receiving the mailed HPDs (with or without information) compared to participants receiving other interventions. Participants receiving the interactive web-based information had comparable increased use of HPDs to those receiving the static web-based information. Participants receiving the mailed HPDs had more positive situational influences scale scores than other participants. Program satisfaction was highest among mailed and web-based information groups.

CONCLUSIONS

A mailed assortment of hearing protectors was more effective than information. Interactive and static information delivered via web were similarly effective. Programs interested in increasing HPD use among farmers should consider making hearing protectors more available to farmers.

Social Desirability Bias in Self-Reporting of Hearing Protector Use among Farm Operators

OBJECTIVE

The purposes of this study were (i) to examine the relationship between reported hearing protector use and social desirability bias, and (ii) to compare results of the Marlowe-Crowne social desirability instrument when administered using two different methods (i.e. online and by telephone).

METHODS

A shortened version of the Marlowe-Crowne social desirability instrument, as well as a self-administered instrument measuring use of hearing protectors, was administered to 497 participants in a study of hearing protector use. The relationship between hearing protector use and social desirability bias was examined using regression analysis. The results of two methods of administration of the Marlowe-Crowne social desirability instrument were compared using t-tests and regression analysis.

RESULTS

Reliability (using Cronbach's alpha) for the shortened seven-item scale for this sample was 0.58. There was no evidence of a relationship between reported hearing protector use and social desirability reporting bias, as measured by the shortened Marlowe-Crowne. The difference in results by method of administration (i.e. online, telephone) was very small.

CONCLUSIONS

This is the first published study to measure social desirability bias in reporting of hearing protector use among farmers. Findings of this study do not support the presence of social desirability bias in farmers' reporting of hearing protector use, lending support for the validity of self-report in hearing protector use in this population.

Protocol of a randomized controlled trial of hearing protection interventions for farm operators

Background

Hearing loss and tinnitus are prevalent in America, and noise-induced hearing loss is a leading cause of hearing loss. Noise-induced hearing loss has negative impact on quality of life, physical and emotional functioning, social life, and employment. In addition, noise-induced hearing loss results in heavy social and economic burdens on families and communities from all ethnic and socioeconomic groups. Farmers are a group that is particularly high risk for noise-induced hearing loss, and is underserved by programs designed to limit that risk. They are among the most noise-exposed group of workers, and experience the second highest prevalence of noise-induced hearing loss among all occupational categories. In agriculture, 1.5 million workers (43.3%) report exposure to hazardous noise. Although use of hearing protection devices (HPDs) would protect them from noise-induced hearing loss, use among farmers is low.

Methods/Design

The purpose of this project is to compare the effectiveness of several approaches to influencing hearing protector use. Approaches include: a) an interactive, predictors-based intervention delivered via the Internet; b) a static informational web site; and c) a mailed sampler of hearing protectors. The goals are to further develop an intervention to promote farmers’ use of HPDs, and compare the effectiveness of the interventions delivered in various combinations. Participants will include 701 farmers. Sites will be affiliates of a major farmer organization. Data will be collected at baseline, 6, and 12 months. A random intercept mixed model will be used to explore the fixed effects of the three NIHL prevention interventions over time while adjusting for age and gender. This project will involve a partnership between the University of Michigan and a major farmer organization to accomplish project aims.

Discussion

Results of this study will be used to inform future research-to-practice studies to increase hearing protector use. Increased use of hearing protectors is expected to reduce rates of noise-induced hearing loss and other negative effects of high noise exposure, and improve quality of life in this high-risk and underserved group.

Trial registration

Clinicaltrials.gov NCT01454895 Registered 14 October, 2011.

Strategies to enhance participant recruitment and retention in research involving a community-based population

Challenges associated with recruiting and retaining community-based populations in research studies have been recognized yet remain of major concern for researchers. There is a need for exchange of recruitment and retention techniques that inform recruitment and retention strategies. Here, the authors discuss a variety of methods that were successful in exceeding target recruitment and retention goals in a randomized clinical trial of hearing protector use among farm operators. Recruitment and retention strategies were 1) based on a philosophy of mutually beneficial engagement in the research process, 2) culturally appropriate, 3) tailored to the unique needs of partnering agencies, and 4) developed and refined in a cyclical and iterative process. Sponsoring organizations are interested in cost-effective recruitment and retention strategies, particularly relating to culturally and ethnically diverse groups. These approaches may result in enhanced subject recruitment and retention, concomitant containment of study costs, and timely accomplishment of study aims.

WITHDRAWN: Interventions to promote the wearing of hearing protection

Review withdrawn from Issue 11, 2013 of The Cochrane Library due to the identification of an error in the data analysis. This review no longer remains a priority topic for the Cochrane Ear, Nose & Throat Disorders Group and therefore the review will not be corrected, updated and republished by this group.

The editorial group responsible for this previously published document have withdrawn it from publication.

Review of interventions to increase hearing protective device use in youth who live or work on farms

AIMS AND OBJECTIVES

To identify and compare hearing protection interventions for youth working and living on farms.

BACKGROUND

Noise-induced hearing loss represents a significant risk factor for injury, disability and death in agricultural populations due to an inability to receive sensory information that can indicate dangerous situations. Despite the availability of hearing protection devices, rates of utilisation remain low, while rates of noise-induced hearing loss are high within the agricultural youth population.

DESIGN

Comprehensive review of the literature.

METHOD

Electronic database searches were conducted to identify research studies of hearing protection interventions for youth living or working on farms.

RESULTS

Three intervention studies were identified as meeting the review criteria, with additional reanalysis studies based on the original intervention studies. The intervention studies demonstrated increased use of hearing protection devices among youth who received the interventions compared to the control groups although audiometry testing results were not improved as a result of the intervention.

CONCLUSIONS

The findings of this review highlight the need for additional research into the effectiveness of hearing protection device use as a noise-induced hearing loss preventative measure in youth who live or work on farms and the creation of effective interventions to increase hearing protection device use and decrease Noise-induced hearing loss risk.

RELEVANCE TO CLINICAL PRACTICE

It is recommended that nurses be educated in the areas of health promotion relevant to farming communities to be able to effectively meet their rural clients' needs in relation to noise-induced hearing loss. Working with youth, families, and schools, as well as developing community partnerships, can facilitate the dissemination of hearing protection promotion.

Effects of common agricultural tasks on measures of hearing loss

BACKGROUND

Among agricultural populations, hearing loss caused by excessive noise exposure is common. However, examinations of associations between exposure to agricultural tasks and hearing loss are limited.

METHODS

Audiometry and lifetime exposure to 11 agricultural tasks were analyzed among 1,568 participants. Gender stratified multivariable linear regression was used to estimate associations between exposure duration and three hearing loss metrics.

RESULTS

Among men, significant associations were observed between hearing loss and hunting or target shooting, all-terrain vehicle (ATV) or motorcycle riding, chain saw use, electric or pneumatic tool use, living on a farm, and all agricultural tasks combined. When all significant exposure metrics were included in a single model, associations remained for hunting or target shooting, electric or pneumatic tool use and living on a farm. Significant associations were sparse among women, and in all cases paradoxical.

CONCLUSIONS

Despite imprecise estimation of noise exposure, specific agricultural tasks were associated with hearing loss.

Interventions to promote the wearing of hearing protection

BACKGROUND

This is an update of a Cochrane Review first published in The Cochrane Library in Issue 2, 2006 and previously updated in 2009.Noise-induced hearing loss can be prevented by eliminating or lowering noise exposure levels. Where the source of the noise cannot be eliminated, workers have to rely on hearing protection equipment. Several trials have been conducted to study the effectiveness of interventions to influence the wearing of hearing protection.

OBJECTIVES

To evaluate the effectiveness of interventions to enhance the wearing of hearing protection among persons regularly exposed to high noise levels.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 8 April 2011.

SELECTION CRITERIA

We included studies if they had a randomised design, if they were among noise exposed (> 80 dB(A)) persons, if they included an intervention to promote the wearing of hearing protection (compared to another intervention or no intervention), and if the outcome measured was the amount of use of hearing protection or a proxy measure thereof.

DATA COLLECTION AND ANALYSIS

Two authors selected relevant trials, assessed risk of bias and extracted data.

MAIN RESULTS

Seven studies, involving 4670 participants, were included.A computer-based intervention lasting 30 minutes, tailored to the risk of an individual worker, was not found to be more effective than a video providing general information among workers, around 80% of whom already used hearing protection.A four-year school-based hearing loss prevention programme found that the intervention group was twice as likely to wear some kind of hearing protection as the control group that received a baseline hearing test and two additional tests at years two and three.We conducted two meta-analyses for the comparisons 'tailored strategy (the use of communication or other types of interventions that are specific to an individual or a group and aim to change behaviour) versus non-tailored strategy' and 'tailored strategy versus a commercial video on the use of hearing protection' to look at mean percentage use of hearing protective devices (HPDs), that showed improvement in the mean use of HPDs for the tailored group. A meta-analysis of the comparison 'mixed interventions' (classroom instruction, distribution of HPDs, mailings, noise level assessments and audiometric testing) versus control (audiometric testing alone) also showed improvement in self reported use of HPDs when shooting firearms.Tailored education showed an improvement in HPD use of 8.3% versus targeted education (6.1%).

AUTHORS' CONCLUSIONS

The evidence found in this review shows that some interventions improve the mean use of hearing protection devices compared to non-intervention. Future trials should have standard outcomes and interventions to allow the combining of results in meta-analysis.

Validation of a questionnaire to identify hearing loss among farm operators

Workers in certain industries (e.g., agriculture) do not participate in a hearing conservation program and rarely receive this important preventive care. The National Institute for Deafness and Communication Disorders (NIDCD) has published a questionnaire to assess a person's need for medical examination of their hearing. The use of a self-administered questionnaire may pose a simple, low cost opportunity to assess the hearing health of workers not included in a hearing conservation program. However, the validity of the NIDCD questionnaire has not been tested. A study was conducted to compare the results of audiometric screening and the NIDCD questionnaire in identifying persons at risk for hearing impairment who may benefit from a medical referral. Data were collected from 103 farm operators at a regional farm show. Receiver-operator characteristic curves, measuring the ability of the questionnaire to correctly classify those with and without the disease suggested that the level of performance of the questionnaire as a whole, ranged from 0.74 to 0.69 (fair to poor). However, selected questionnaire items (e.g., Do you have to strain to understand conversations?) had moderate agreement (0.38 to 0.41) with screening audiogram results. Overall, the 10-item instrument did not perform as well as instruments with fewer items reported in separate studies. These findings suggest that, while less desirable than audiometry, alternative self-administered instruments might perform the better in this group. This approach may be useful as an alternative screening method to detect risk of hearing loss and identifying the need for medical evaluation of hearing sensitivity, particularly among farm operators.

Interventions to promote the wearing of hearing protection

BACKGROUND

This is an update of a Cochrane Review first published in The Cochrane Library in Issue 2, 2006 and previously updated in 2009.Noise-induced hearing loss can be prevented by eliminating or lowering noise exposure levels. Where the source of the noise cannot be eliminated, workers have to rely on hearing protection equipment. Several trials have been conducted to study the effectiveness of interventions to influence the wearing of hearing protection.

OBJECTIVES

To evaluate the effectiveness of interventions to enhance the wearing of hearing protection among persons regularly exposed to high noise levels.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 8 April 2011.

SELECTION CRITERIA

We included studies if they had a randomised design, if they were among noise exposed (> 80 dB(A)) persons, if they included an intervention to promote the wearing of hearing protection (compared to another intervention or no intervention), and if the outcome measured was the amount of use of hearing protection or a proxy measure thereof.

DATA COLLECTION AND ANALYSIS

Two authors selected relevant trials, assessed risk of bias and extracted data.

MAIN RESULTS

Seven studies, involving 4670 participants, were included.A computer-based intervention lasting 30 minutes, tailored to the risk of an individual worker, was not found to be more effective than a video providing general information among workers, around 80% of whom already used hearing protection.A four-year school-based hearing loss prevention programme found that the intervention group was twice as likely to wear some kind of hearing protection as the control group that received a baseline hearing test and two additional tests at years two and three.We conducted two meta-analyses for the comparisons 'tailored strategy (the use of communication or other types of interventions that are specific to an individual or a group and aim to change behaviour) versus non-tailored strategy' and 'tailored strategy versus a commercial video on the use of hearing protection' to look at mean percentage use of hearing protective devices (HPDs), that showed improvement in the mean use of HPDs for the tailored group. A meta-analysis of the comparison 'mixed interventions' (classroom instruction, distribution of HPDs, mailings, noise level assessments and audiometric testing) versus control (audiometric testing alone) also showed improvement in self reported use of HPDs when shooting firearms.Tailored education showed an improvement in HPD use of 8.3% versus targeted education (6.1%).

AUTHORS' CONCLUSIONS

The evidence found in this review shows that some interventions improve the mean use of hearing protection devices compared to non-intervention. Future trials should have standard outcomes and interventions to allow the combining of results in meta-analysis.

Effects of a low intensity intervention to increase hearing protector use among noise-exposed workers

BACKGROUND

Farm operators experience exposure to high noise and high prevalence of noise-induced hearing loss, but use of hearing protection in this worker group is low. The purpose of this study was to test a brief intervention to increase farm operators' use of hearing protection.

METHODS

In this one-group pre- and post-test study, a random sample of 32 members of a farmers' organization was supplied a variety of hearing protectors. Participants received an assortment of hearing protectors by mail with manufacturer's instructions for use.

RESULTS

Mean pre-intervention hearing protector use when in high noise in this group was 23% (SD 29). Of the 32 participants, 27 (84%) were exposed to hazardous noise during the study period. Post-intervention mean use of HPDs was 64%, an increase of 41% (t = 5.26, P < 000).

CONCLUSION

Results of this study suggest that overall, hearing protectors were acceptable to farm operators, and that a brief mailed intervention is feasible.

Interventions to promote the wearing of hearing protection

BACKGROUND

This is an update of a Cochrane Review first published in The Cochrane Library in Issue 2, 2006. The original review was republished in Issue 2, 2009 with feedback incorporated.Noise induced hearing loss can be prevented by eliminating or lowering noise exposure levels. Where the source of the noise cannot be eliminated, workers have to rely on hearing protection equipment. Several trials have been conducted to study the effectiveness of interventions to influence the wearing of hearing protection.

OBJECTIVES

To evaluate the effectiveness of interventions to enhance the wearing of hearing protection among persons regularly exposed to high noise levels.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; mRCT and additional sources for published and unpublished trials. The date of the most recent search was 4 February 2009.

SELECTION CRITERIA

We included studies if they had a randomised design, if they were among noise exposed (> 80 dB(A)) persons, if they included an intervention to promote the wearing of hearing protection (compared to another intervention or no intervention), and if the outcome measured was the amount of use of hearing protection or a proxy measure thereof.

DATA COLLECTION AND ANALYSIS

Two authors selected relevant trials, assessed methodological quality and extracted data.

MAIN RESULTS

Six studies, involving 3917 participants, were included.A computer-based intervention lasting 30 minutes, tailored to the risk of an individual worker, was not found to be more effective than a video providing general information among workers, around 80% of whom already used hearing protection.A four year school-based hearing loss prevention programme found that the intervention group was twice as likely to wear some kind of hearing protection as the control group that received baseline hearing test and two additional tests at years two and three.We conducted two meta-analyses for the comparisons 'tailored strategy (the use of communication or other types of interventions that are specific to an individual or a group and aim to change behaviour) versus non-tailored strategy' and 'tailored strategy versus a commercial video on the use of hearing protection' to look at mean percentage use of hearing protective devices (HPDs), that showed improvement in the mean use of HPDs for the tailored group.Tailored education showed an improvement in HPD use of 8.3% versus targeted education (6.1%).

AUTHORS' CONCLUSIONS

The evidence found in this review shows that some interventions improve the mean use of hearing protection devices compared to non-intervention. Future trials should have standard outcomes and interventions to allow the combining of results in meta-analysis.

Too late smart: farmers' adoption of self-protective behaviors in response to exposure to hazardous noise

Farmers are exposed to hazardous noise from equipment and livestock and experience high rates of noise-induced hearing loss (NIHL); however, their use of hearing protection devices (HPDs) is low. The purpose of this study was to describe farmers' personal experiences using HPDs, influencing others' use of HPDs, and overcoming barriers to the use of HPDs. A purposive sample of farmers who reported a high frequency of HPD use was selected for face-to-face interviews. Findings indicated that farmers have frequent exposure to hazardous noise. They described their motivation to adopt protective behaviors to avoid hearing loss, noise annoyance, or tinnitus. Many tried to influence others' use of HPD, particularly family members. These farmers have developed a variety of methods to ensure convenient access to HPDs when needed, and have developed effective techniques for overcoming common barriers to protection. Findings from this study will be used to form the foundation for future studies aimed at developing and testing an intervention to increase HPD use and decrease rates of NIHL among farmers.