International Journal of Pediatric Otorhinolaryngology 78 (2014) 604–609

Effectiveness of a preventive campaign for noise-inducedhearing damage in adolescents

Annick Gilles a,b,c,*, Van de Heyning Paul a,b,c

a University Department of Otorhinolaryngology and Head & Neck Surgery, Antwerp University Hospital, Edegem, Belgiumb Faculty of Medicine, Campus Drie Eiken, Antwerp University, Wilrijk, Belgiumc Tinnitus Research Initiative Centre (TRI), Antwerp University Hospital, Edegem, Belgium

A R T I C L E I N F O

Article history:

Received 14 November 2013

Received in revised form 6 January 2014

Accepted 8 January 2014

Available online 17 January 2014

Keywords:

Preventive campaign

Hearing protection

Effectiveness, Youth attitudes to noise scale

Beliefs about hearing protection and

hearing loss

Tinnitus

A B S T R A C T

Objectives: Many studies have documented a high incidence of hearing loss and tinnitus in adolescents

after recreational noise exposure. The prevalence of noise-induced symptoms is in contradiction to the

low preventive use of hearing protection. The effects of preventive campaigns on the attitudes toward

noise in young people are under debate. The aim of the present study is to investigate whether a

preventive campaign can alter attitudes toward noise in adolescents and whether this results in an

increase of hearing protection use in this population.

Methods: A cohort of 547 Flemish high school students, aged 14 to 18 years old, completed a

questionnaire prior to and after a governmental campaign focusing on the harmful effects of recreational

noise and the preventive use of hearing protection. At both occasions the attitudes toward noise and

toward hearing protection were assessed by use of the youth attitudes toward noise scale (YANS) and the

beliefs about hearing protection and hearing loss (BAHPHL), respectively. These questionnaires fit into

the model of the theory of planned behavior which provides a more clear insight into the prediction of a

certain behavior and the factors influencing that behavior.

Results: The score on the YANS and the BAHPHL decreased significantly (p < 0.001) implying a more

negative attitude toward noise and a more positive attitude toward hearing protection. The use of

hearing protection increased significantly from 3.6% prior to the campaign to 14.3% (p = 0.001) post

campaign in students familiar with the campaign.

Conclusions: Measurable alteration of all the variables in the theory of planned behavior caused an

increase of the intentions to use hearing protection as well as the actual use of hearing protection. The

present study shows the usefulness of the theory of planned behavior to change and guide adolescents’

preventive actions toward noise damage. In addition, preventive campaigns can establish attitude and

behavioral adjustments. However, the long term effects of preventive campaigns should be investigated

in future research.

� 2014 Elsevier Ireland Ltd. All rights reserved.

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International Journal of Pediatric Otorhinolaryngology

jo ur n al ho m ep ag e: ww w.els evier . c om / lo cat e/ i jp o r l

Introduction

As a consequence of loud music exposure, noise-induced hearingdamage in adolescents and young adults increased over the lastyears [1–3]. Besides measurable hearing loss on the audiogram alsoother symptoms such as tinnitus, the perception of an auditoryphantom sound in the form of ringing, buzzing, roaring or hissing inthe absence of an external sound source [4], is a frequently occurringphenomenon in young people after recreational noise exposure.

* Corresponding author at: Department of Otorhinolaryngology and Head & Neck

Surgery, University Hospital Antwerp, Wilrijkstraat 10, 2650 Edegem, Belgium.

Tel.: +32 3 821 52 80.

E-mail address: annick.gilles@uza.be (A. Gilles).

0165-5876/$ – see front matter � 2014 Elsevier Ireland Ltd. All rights reserved.

http://dx.doi.org/10.1016/j.ijporl.2014.01.009

Furthermore, noise-induced tinnitus, can also occur solitarily [5]without the presence of a hearing loss measured by the classicalaudiometry technique. The fact that up to 30% of outer hair cell lossmay occur without any associated detectable hearing loss [6],implicates that the absence of a measurable hearing loss does notexclude cochlear or neural damage and that tinnitus clearly is a signof overexposure [5,7]. The reported incidence of regularly temporarytinnitus in adolescents due to recreational noise varies between 60%and 85% [8–14]. Moreover, permanent noise-induced tinnitus isalready experienced by 10% to 18% of young people [8,9,15]. A largediscrepancy between the high prevalence of noise-induced symp-toms and the low rate of preventive measures in the form of hearingprotection (HP) has been reported several times by previousresearch [9,16,17]. Whether hearing education programs andcampaigns prompt adolescents to display hearing protective

A. Gilles, V.H. Paul / International Journal of Pediatric Otorhinolaryngology 78 (2014) 604–609 605

behavior in noisy situations is under debate. Weichbold andZorowka found that a hearing protection program yielded limitedbehavioral changes in high school students going from 0% prior tothe campaign to 3.7% HP use one year later [18] and also insubsequent studies the effects of hearing education campaigns arequestioned [19,20]. The question is whether providing informa-tion and thus increasing the knowledge concerning the risks ofloud music exposure, is sufficient to cause behavioral changes inadolescents. The theory of planned behavior (TPB) provides moreinsight into the prediction of health related behavior consideringalso other influencing factors besides knowledge. Despite the factthat information accuracy unequivocally plays a huge role [21],the TPB states that the reciprocity between attitudes toward aparticular behavior, subjective norms and perceived behavioralcontrol defines the intentions to behave in a certain way. Attitudesare regarded as beliefs about the outcome determined by positiveor negative evaluation of self-performance of the particularbehavior. A subjective norm is the extent to which an individual’sperception about the particular behavior is influenced bysignificant others (parents, peers, teachers, etc.) weighted bythe compliance with such influence. Finally, perceived behavioralcontrol is an individual’s belief about the presence of factors thatfacilitate or impede the performance of the health-relatedbehavior [22,23]. Previous research focused on adolescents’attitudes toward noise by use of the youth attitudes towardnoise scale (YANS), a 19-item questionnaire focusing on differentaspects of noise [17,24]. A recent study by Widen investigatingpotential health promotion variables associated with adolescents’HP use at concerts showed that the TPB is also useful in theprediction of hearing protection behavior [25]. The present studyreports on the behavioral effects of a Flemish governmentalhearing education campaign on adolescents evaluating the effectof changes in attitudes, social norms and perceived behavioralcontrol as explained by the TPB.

Methods

Governmental campaign

On the eve of the festival season of 2011 (May) a governmentalpreventive campaign (from now on referred to as PrevC) wasreleased in the Flemish part of Belgium (Dutch speaking part) inorder to prevent hearing damage caused by noise exposure. Thecampaign was called ‘Iets Minder is de Max’ which can betranslated as ‘Anything less is the max’ targeting high schoolstudents aged 14 to 18 years old. The campaign was promoted viavarious ways such as television and radio commercials, socialnetwork sites (Facebook/Twitter), posters and a website(www.ietsminderisdemax.be). PrevC had the intention to makeyoung people more aware of the risks of loud music and thereforeincrease the use of HP in noisy situations and to effectuate a morecontrolled and responsible use of personal listening devices(PLD’s).

Subjects

A cohort of 547 high school students (mean age = 16.8 yearsold � 0.8) completed the same questionnaire twice: the first time inMarch 2011 (prior to the campaign) and the second time in November2011 (six months after the campaign). The principals of several highschools were contacted by phone with the suggestion to participate inthe study. This approach was chosen because this allowed to providesufficient information concerning the study and to answer allquestions. After a positive verbal agreement, all participating schoolswere sent a written confirmation of participation by e-mail includinga copy of the questionnaire. As the study is performed by the

administering of a questionnaire, the high school principals were inthis case considered as the caretakers of the minors. All ques-tionnaires were administered during class and students had 15 mintime to complete the questionnaire. As such, the situation in whichthe completion of the questionnaire occurred was quite similar for allstudents and controlled by the teacher which resulted into a very highresponse rate. Originally, 600 questionnaires were sent to theparticipating high schools of which 547 (=91%) were analyzed anddescribed in the current paper. 53 questionnaires were not includedin the present paper because they were incomplete. Students werenot at all obliged to complete the questionnaire so the completion ofthe questionnaire was considered as a silent approval for participa-tion. As such, an additional informed consent was not documented.The approach of the present study was approved by the IRB of theUniversity Hospital Antwerp in 2011 prior to the administration ofthe first questionnaire.

Questionnaire content

Questions concerning PrevC

Concerning the familiarity with PrevC following yes–noquestion was asked: ‘‘Have you heard of the campaign PrevC?’’In case of a positive answer the students also needed to respond tothe question whether one thought that the campaign renderedsufficient information concerning the risks of loud music exposure(yes–no) and whether the campaign incited to more carefullyprotect the hearing by use of HP (yes–no).

Use of personal listening devices

One was asked to indicate whether one used PLD’s. In case of apositive answer, the respondents needed to indicate how much(answer possibilities: daily, weekly, monthly, yearly) and how long(answer possibilities: not applicable, less than 30 min, between30 min and 1 h, between 1 and 2 h and longer than 2 h) onelistened to PLD’s on average. Finally the volume settings of PLD’swere assessed by use of a percentage scale going from 0% to 100% ofthe total capacity of the device.

Youth attitudes to noise scale

A validated Dutch version [26] of the Youth Attitudes to NoiseScale (YANS) [27] was included in the questionnaire. The YANSconsists of nineteen items considering the following themes: (a)attitudes toward noise associated with elements of youth culture,e.g. attending discos, (b) attitudes toward the ability to concentratein noisy environments, (c) attitudes to daily noises, e.g. traffic noiseand (d) attitudes toward influencing the sound environment, e.g. inschool. All items need to be scored on a five-point Likert scale goingfrom ‘totally agree’ to ‘totally disagree’. For a more extensivereview on the validation of the Dutch YANS we refer the reader toAppendix A.

Beliefs about hearing protection and hearing loss

The beliefs about hearing protection and hearing loss (BAHPHL)was originally developed by the National Institute for OccupationalSafety and Health in order to assess the beliefs concerning hearingprotection and hearing loss among industrial workers [28,29]. Theoriginal BAHPHL was validated in Dutch [26] in which the itemsconcerning industrial noise were omitted or altered in order tobecome applicable to adolescents and young adults. Therefore theDutch version contains 7 items instead of the original 8 (the eightcategory was omitted): (a) Susceptibility to hearing loss, (b)severity of consequences of hearing loss, (c) benefits of preventiveactions, (d) barriers to preventive actions, (e) behavioral inten-tions, (f) social norms and (g) self-efficacy. For a more extensivereview on the validation of the Dutch BAHPHL we refer the readerto Appendix B.

Attitudes

YANS

Susceptibility to hearing loss (BAHPHL -factor 1)

Severity of consequ ences of heari ng loss (BAHPHL- fac tor 2)

Social norms (BAHPHL – factor 6)

Benefits of preventiv e action (BAHPHL –factor 3)

Barriers to preve ntive action (BAHPHL –factor 4)

Self-efficacy (BAHPHL – factor 7)

Subjective norms

Perceived behavioral control

Intention Behavior (use of HP)

Fig. 1. Implementation of the used questionnaires in the model of the theory of planned behavior.

Fig. 2. Change in score on the total YANS with the different factors described in

terms of arithmetic mean with the 95% confidence intervals (* = significant

difference).

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Statistical analysis

Statistical analyses were performed with a statistical softwarepackage (SPSS 17.0, Inc., Chicago, IL, USA). Independent non-parametric tests were used in order to identify changes of attitudestoward noise (changes in YANS scores), changes of attitudestoward HP (changes in BAHPHL scores) and changes in HP use. Thelevel of statistical significance was defined as p < 0.05.

Theory of planned behavior

The questionnaire administered to the students, can be seenin the light of the TPB. Fig. 1 illustrates the influencing factors onthe intentions to and eventually the actual use of HP. Theattitudes toward noise are evaluated by use of the YANS. Theinformation concerning the subjective norm, the extent to whichan individual’s perception about the particular behavior isinfluenced by significant others (parents, peers, teachers, etc.),can be provided by factor one, two and six of the BAHPHL. Factorone contains ones’ believes concerning the susceptibility tohearing loss, factor two believes concerning the consequences ofhearing loss and factor six believes concerning social norms. Asall these factors are highly influenced by significant others, theywere all included under ‘subjective norms’ in the figure. Inaddition, factor three (beliefs concerning benefits of preventiveaction), factor four (believes concerning barriers to preventiveaction) and factor seven (beliefs concerning self-efficacy), are allpart of the individual’s belief about the presence of factors thatfacilitate or impede the performance of the health-relatedbehavior and therefore included under ‘perceived behavioralcontrol’ in the figure.

Results

27.4% of the questioned students came in contact with somekind of prevention campaign at one or multiple settings of which9.1% reported to have knowledge concerning the PrevC inparticular.

The scores on the YANS pre and post-campaign are illustrated inFig. 2. A significant decrease (p < 0.001) of the total YANS score aswell as the separate factors (with exception of factor 2 whichincreased significantly) score was apparent, implying the devel-opment of a more negative attitude toward noise after thecampaign. In this context the significant decrease of factor 1(p < 0.001) is worth mentioning as this factor contains itemsconcerning noise levels in night clubs and other social activities.

In Fig. 3 the scores on the BAHPHL are illustrated in a similarway where also a significant decrease (p < 0.001) of the totalBAHPHL score after the campaign was apparent. Looking at thedifferent factors of the BAHPHL, factor 1 (‘susceptibility to hearingloss’) and factor 2 (‘severity of consequences of hearing loss’)showed no significant differences between the two surveys. Theother five factors, however, showed very significant decreasesimplying the development of a more positive attitude toward HP.

Two items of the BAHPHL (item 6 and 24) were analyzed morespecifically. The influence of whether one knew the campaign onitem 6 (‘I wear hearing protectors during recreational noiseexposure’) and item 24 (‘I intend to wear hearing protectors in thefuture’) is more precisely analyzed in Fig. 4. Prior to the campaign3.6% of these respondents reported to use HP in noisy situations. Inthe group who reported to know the campaign PrevC thispercentage increased significantly going to 14.3% (p = 0.001)compared to those who did not know PrevC where there wasbarely a non-significant increase apparent (+0.8%) with 4.4% usingHP. The effect of the campaign was also apparent in item 24 wherethe intentions to use HP somewhere in the future were assessed.

Fig. 3. Change in score on the total BAHPHL with the different factors described in terms of arithmetic mean with the 95% confidence intervals (* = significant difference).

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Before the campaign 8.2% of the students reported they had theintention to use HP in the future whereas this percentagesignificantly increased up to 39.3% (p = 0.001) post-campaign inthe group familiar with campaigns compared to 22.3% (p = 0.009)in the group not familiar with campaigns. Of all students who camein contact with preventive education of any kind, 46.6% felt theywere thoroughly informed. However, the use of PLD’s did not alterafter the campaign as no significant decrease in PLD use or avolume reduction could be found.

Fig. 4. Left: Percentage of actual hearing protection use in students prior (pre) to the cam

familiar with the campaign (PrevC) or not (no PrevC). Right: Percentage of intentions

(* = significant difference).

Discussion and conclusions

The present study illustrated some measurable effects in thegroup who was familiar with PrevC. First, both the scores on theYANS and the BAHPHL decreased significantly. The attitudestoward noise shifted toward a more negative attitude after thecampaign compared to the pre-campaign survey, meaning thatmore students considered noise as something dangerous, as a riskfactor. In addition, a more positive attitude toward HP use was

paign and after the campaign. A distinction was made between whether one was

to use hearing protection in the future prior to the campaign and post campaign.

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reflected by the decrease of scores on the BAHPHL. Dell et al. alsofound a significant decrease of pro-noise attitudes in children agedbetween 12 and 14 years old after a hearing conservation program[30]. The present study showed that the same effects are true forolder adolescents aged between 14 and 18 years old. However, it ispossible that those students who were already more negativelyorientated toward noise, are more prawn to the effect of preventivecampaigns compared to those who previously had a neutral orpositive attitude toward noise. Unfortunately, as all questionnaireswere filled out anonymously because of privacy reasons, suchanalyses could not be performed. Nevertheless, the attitudestoward a certain behavior is the best predictor of the behavior itself[22]. Hence, in case when one is more negative toward noise andmore positive toward HP, one will be more inclined to use HP. In aprevious study where the efficacy of a hearing protection programwas also evaluated by administering of the same questionnairepre- and post campaign, the use of HP rose by 3.7% [19] by whichthe authors concluded that the use of HP was not significantlyaltered. The present study showed a more positive outcomeconcerning the effect of the campaign on the use of HP where alongwith the attitude adjustment (reflected in the scores on the YANSand BAHPHL) there was a fourfold increase of HP (+10.7%) use inthe group that was familiar with the campaign compared to only aslight non-significant increase in the group that did not come incontact with the campaign (+0.8%). Interestingly, the intentions touse HP increased significantly in both groups but only thosestudents familiar with PrevC more often performed the actualbehavior itself. Concerning PLD listening behaviors, no measurablebehavior was found in the present study which is in accordancewith a previous study of Weichbold and Zorowka [18,19].Concerning future research, the authors suggest that also thereasons for not using HP should be further assessed. Previousstudies pointed out that young people are knowledgeable aboutthe possible ear damage due to leisure noise [8,16,31]. However,the use of HP remains limited [8,11,24]. Bogoch et al. questionedyoung people attending a rock concert concerning their percep-tions about the risk of noise-induced hearing loss [16]. Approxi-mately 75% thought that is was likely to develop noise-inducedhearing loss. Unfortunately, more than 80% reported not to use HP.On the other hand, the authors revealed a willingness of the publicto use HP in the future, especially when distributed for free at thedoor of the venue. Such findings suggest that the cost price of goodHP could be one of the main reasons for the overall non-use inyoung people. Future research should explore more on the reasonsfor the (non)-use of HP in order to better anticipate this problem inthe future preventive campaigns as the present study confirmedthe capability of hearing protection campaigns as an efficient wayto promote the use of HP and safe use of HP [32]. Hearingprotection campaigns managed to make alterations on everyaspect of the model of TPB as illustrated in Fig. 1 and thusincreasing the intentions to use HP (39.3% wanted to use HP in thefuture) but also increasing the present actual use of HP (a fourfoldincrease from 3.6% to 14.3% HP use). As a result, it is suggested thatthe government as well as private organizations should keep oninvesting in such campaigns in order to inform young people aboutthe damaging effects of leisure noise and to prevent irreversible eardamage. The authors believe that the repetition of such campaignswill effectuate further robust attitude adjustments in adolescents.In addition, future research should target the long term effects ofpreventive campaigns in order to establish the most efficientrepetition rate.

Acknowledgments

The authors are grateful for the financial support of the StavrosNiarchos Foundation (SNF) as well as of the TOP-BOF mandate of

the University Antwerp. A special thanks goes to Kris Ulenaers forthe help in data management and to the Flemish Agency for Careand Health, Division of Public Health Surveillance, EnvironmentalHealth Section for the help in the distribution of the questionnairesand the close cooperation. We would also like to express ourgratitude to the high schools involved for their enthusiasm andcooperation.

Appendix A. Supplementary data

Supplementary data associated with this article can be found, in

the online version, at http://dx.doi.org/10.1016/j.ijporl.2014.01.009.

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