Abstract
Background: 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.
Objectives: This study tested the effectiveness of an individually tailored multimedia intervention to increase use of HPDs by factory workers.
Methods: 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.
Results: 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.
Conclusions: 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 the United States it is estimated that more than 30 million workers are exposed to harmful levels of noise on the job (National Institute for Occupational Safety and Health [NIOSH], 1996), thus making it one of the most common occupational health hazards today. Industrial or agricultural processes and machinery account for much of the noise exposure (U.S. Department of Health and Human Services [USDHHS], 1988). Significant harmful effects of loud noise include noise-induced hearing loss (NIHL); tinnitus (noises or ringing in the ears); psychological effects such as anxiety, depression, job stress, and decreased job satisfaction (Bhattacharga, Aparna, Tripathi, & Chatterjee, 1985;Melamed, Luz, & Green, 1992); and physiologic effects such as changes in heart rate, blood pressure, and increases in accidents/illnesses (Melamed et al., 1992;Johsson & Hansson, 1997;Lusk, Haggerty, Gillespie, & Caruso, 2002).
Because of this significant occupational health hazard, the Occupational Safety and Health Administration (OSHA) has mandated workplace Hearing Conservation Programs for industrial worksites (U.S. Department of Labor [USDL], 1983). As a part of these programs, engineering or administrative controls should be used as the first line of defense to reduce noise. However, implementation of these types of controls may not always be feasible or practical or may be insufficient to reduce noise to a safe level. When this occurs, hearing protection devices (HPDs) should always be used by workers (when exposed to loud noise) to prevent NIHL (Berger, 2000;Dear, 1998;Savell & Toothman, 1987). Although there is no comprehensive database available regarding the extent of HPD use, previous research has shown that construction and factory workers use HPDs only a fraction of the time (18% to 70%) when they should be worn (Lusk, Kerr, & Kauffman, 1998;Lusk, Ronis, & Kerr, 1995). Therefore, it is essential that workers increase their use of HPDs, thus assuming personal responsibility for preventing NIHL. As health professionals, occupational health nurses conduct audiometric screening tests, provide education to workers regarding the dangers of loud noise, and assist them in preventing NIHL.
Although prior research has shown that there is a strong need to change worker behavior regarding use of HPDs, the research base regarding occupational behavior change programs is sparse. In a review of 36 intervention research studies in occupational health and safety, Goldenhar and Schulte (1994) noted a number of methodological problems including lack of a theoretical basis, small sample size, and inadequate intensity to cause the desired change. They also noted that most studies were either quasi-experimental (including nonrandom assignment) or nonexperimental (lack of a control group). Only one study was found that investigated hearing protection using a behavioral intervention (Ewigman, Kivlahan, Hosokawa, & Horman, 1990). While this intervention did result in changes in knowledge, attitudes, beliefs, and behaviors toward use of hearing protection, it lacked a control group to assess the effect of the intervention. Fishbein and associates (1991) have noted that theory-based research has the best potential to enhance the development of successful new interventions and underscored the need for all behavioral intervention programs to be guided by a theoretical framework. However, prior reviews of studies involving changes in workplace practices (Goldenhar & Schulte, 1994;McAfee & Winn, 1989) have noted that few of the behaviorally focused intervention studies had a theoretical basis.
Subsequent to these reviews, Lusk and colleagues (1999) tested the effectiveness of a theory-based intervention delivered to groups of workers working in three trades. Plumber/pipefitters and their trainers showed significant increases in use of HPDs at the 1-year posttest, while operating engineers and carpenters did not. However, mean rate of use was considerably less than the necessary use (100%) to prevent hearing loss, demonstrating the need for further behavior change. Building on the intervention for construction workers, the project described in this paper developed and tested a tailored theory-based intervention and a nontailored theory-based intervention delivered to individuals via computer to increase factory workers' use of HPDs. With increasing accessibility and recent advances in technology, computer-based programs offer a promising method of presenting behavior change messages to large groups of workers. Programs can be produced that combine interesting and relevant video and graphics with the database capabilities and processing power of a desktop computer to provide a feasible and cost-effective approach for behavior-change interventions to individuals and groups (Eakin, Brady, & Lusk, 2001).
Prior studies using a variety of approaches have shown the beneficial effects of tailoring behavior change messages to the individual (Bull, Krueter, & Scharff, 1999;Krueter, Bull, Clark, & Oswald, 1999;Prochaska, DiClemente, Velicer, & Rossi, 1993;Strecher, 1999). In the research project presented here, the intervention was tailored to:
(a) workers' responses to survey questionnaire items (perceptions of benefits, barriers, self-efficacy, interpersonal, and situational factors)
(b) self-reported type of HPD used
(c) perceived hearing ability
(d) self-reported use of HPDs,
thus determining the information they would receive and making it relevant to them
Program content was based on prior research using the Health Promotion Model (Pender, 1987) that identified predictors of hearing protection use among factory and construction workers (Lusk et al., 1995;Lusk, Kerr, Ronis, & Eakin, 1999). In addition, Pender's (1987) Health Promotion Model and Bandura's (1986) Social Cognitive Theory provided the theoretical foundation and guided the process for creating an individually-tailored, multimedia program to change workers' behavior regarding use of HPDs.