Education in the Health Professions

: 2021  |  Volume : 4  |  Issue : 3  |  Page : 116--123

Impact of voice conservation sensitization program in nursing trainees: A pre–post comparison

Krishna Yeshoda1, Rathinaswamy Rajasudhakar1, Shanmugasundaram Lokheshwar2,  
1 Department of Speech-Language Sciences, All India Institute of Speech and Hearing (AIISH), Manasagangothri, Mysuru 570006, Karnataka, India
2 Department of Speech Pathology and Audiology, Sri Devaraj Urs Academy of Higher Education and Research, Tamaka, Kolar 563103, Karnataka, India

Correspondence Address:
Dr. Krishna Yeshoda
Department of Speech-Language Sciences, All India Institute of Speech and Hearing (AIISH), Manasagangothri, Mysuru 570006, Karnataka.


Introduction: Vocal hygiene sensitization programs help in propagating the information about conservation of voice in a swift manner to a target population. Nurses being bridge between patients and doctors help patients understand or convey important information. Hence, nursing trainees formed the target group for the sensitization program on voice conservation and care. Materials and Methods: Ninety-two nursing trainees and their faculty participated in a one-day sensitization program on vocal hygiene. The program consisted of two lectures on the anatomy and physiology of voice and vocal hygiene for voice conservation and voice care. Participants’ familiarity of the topic was assessed using a questionnaire before and after the lectures. Results: There was a significant increase in percent correct response from 77.41% to 91.46% after the program. Out of 10 questions, eight had increase in scores, one had decreased score, and one question remained the same. Conclusion: Improved percent correct response scores of the participants in the post test implied better awareness about the voice production mechanism and conservation of voice and its care. The results could imply that such programs could improve dissemination of information pertaining to voice use, conservation of voice, and helping in reducing the occurrence of voice problems in different groups of professional voice users.

How to cite this article:
Yeshoda K, Rajasudhakar R, Lokheshwar S. Impact of voice conservation sensitization program in nursing trainees: A pre–post comparison.Educ Health Prof 2021;4:116-123

How to cite this URL:
Yeshoda K, Rajasudhakar R, Lokheshwar S. Impact of voice conservation sensitization program in nursing trainees: A pre–post comparison. Educ Health Prof [serial online] 2021 [cited 2022 Jul 6 ];4:116-123
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Full Text


Voice, a mode of communicating meaning, ideas, opinions, etc., refers to the sound generated by vocal fold vibrations in larynx. Larynx, also called as “voice box,” has two main functions, viz., non-speech functions and speech functions. Non-speech functions include the protective reflexes of cough, sneeze, effort closure while swallowing, throat-clearing, and abdominal fixation; and speech functions include speaking and singing. Mechanism of speaking can be generally divided into three parts: lungs, vocal folds (vocal cords), and the articulators. Lungs produce sufficient airflow and air pressure to set vocal folds into motion. The vocal folds vibrate using the airflow from lungs to create audible pulses forming the laryngeal sound source.[1] The sound from the larynx gets modified by the articulators (tongue, palate, cheeks, lips) after the filters either enhance or diminish the sound source.[1],[2],[3],[4]

Vocal hygiene incorporates all aspects of ideal vocal production condition. A complete vocal hygiene program comprises of: a brief introduction of vocal mechanism; conservation of voice, limited talking, a check on vocal pitch and intensity; identification and decreasing abusive behaviors and high-risk verbal circumstances; lubrication and systemic hydration; ideal nutrition; controlling laryngeal reflux, gastroesophageal reflux, and allergies; and environmental factors, reducing the effect of drugs, and lifestyle of choices on voice.[5] Vocal hygiene programs are often conducted to educate professional voice users such as teachers[6],[7],[8] and singers[9],[10] and also other dysphonics.[11],[12]

Ideally, vocal hygiene goals include awareness of several aspects of voice production. However, awareness cannot stand alone to bring changes in vocal behaviors. Mostly, vocal hygiene programs include four fundamental principles: speaking about the amount and type of voice use; reducing phonotraumatic behaviors (talking loudly, clearing throat, vocal abuse, speaking over background noise, and cheering and screaming); increased hydration; and modifying lifestyle issues, which lead to improved vocal health and that include elimination of alcohol, tobacco, caffeinated beverages and recreational drugs, proper diet, adequate sleeping habits, and medications.[5]

Most preventive care about voice problems targets singers, actors, and teachers owing to the importance of voice for pursuing their professional demands. Duffy and Hazlett[6] investigated the primary prevention of occupational dysphonia among 55 training teachers pursuing their Postgraduate Certificate of Education (PGCE) course at the University of Ulster, Northern Ireland. They were randomly assigned to three groups: control, direct, and indirect. Over the year of the PGCE course, their vocal performance was measured: first, before the training and second, after the first teaching practice. Direct and indirect groups received training before the teaching practices. Multidimensional outcomes were assessed using acoustic and self-perceptual measurements. Outcomes of the acoustic measurement revealed that the control group had decline in vocal performance from the first measurement to the second, and the direct group had an improvement and the indirect group had no difference, indicating that the training was helpful. The self-rating scores varied in agreement with the acoustic results.

Efficacy of vocal hygiene education (lecture demonstration) was explored on 65 school teachers in Chennai using a developed questionnaire focussing on a variety of issues/aspects of vocal hygiene.[7] The teachers completed the questionnaire twice (pre- and post-education) and the scores were compared. Overall, the average increase in scores was 9%, and among the different areas explored (non-vocal, vocal, diet, general, and classroom management), the maximum improvement was seen in the vocal category (up to 10%), which indicated that teachers’ awareness of vocal hygiene practices was better after attending the program. According to the authors, the awareness program served in sensitizing the teachers regarding practices that were to be practiced to safeguard their voices and to stay vocally healthy.

Outcome of the vocal hygiene awareness program on students undergoing teacher training in Mysore city was investigated by Rajasudhakar et al.[8] Three audio-video lecture sessions were delivered by experienced speech-language pathologists. The sensitization program was preceded and followed by a questionnaire administration. The results indicated that the average percentage scores increased from 58% (pre-test) to 73% (post-test). The authors reported that the teacher training students’ awareness of voice and its disorders and its preventive care were better after attending the program.

Primary care at small and large private practices such as clinics, schools, and workplace is being provided by nurse practitioners. They work in both collaborative and independent practice arrangements. Furthermore, by taking different roles such as the lead in clinical, management, and accountability in primary care models such as nurse-managed health centers[13] and retail clinics,[14],[15] they are at risk to develop voice problems. The roles and responsibilities of registered nurses in management positions will vary with the size of the organization and the management position held (frontline, middle, senior, or executive).

It is a general tendency to visit a hospital/clinic when a person has a voice problem. In a hospital/clinic setup, nurses assist the otorhinolaryngologist during endoscopic examination and surgical procedures. Collaborating with nurses improves the quality of care, especially chronic care, and practice efficiency.[16] Nurses provide patient education and are fantastic information assets for patients and caregivers. They are indispensable assets in the medical system and are one among the important members in the voice rehabilitation team.[17]

Boone[18] describes a voice problem and voice disorder as ‘when things that we do or fail to do prevent our natural voices being heard and something that needs to be treated by a specialist respectively.” Nurses who work with a laryngologist will usually have more knowledge in the diagnosis and treatment of voice disorders.[19] Knowledge about conservation of voice is important to nurses as they act as a linkage between a doctor and a patient by providing resources and patient education in busy clinical settings. This necessitates the use of regular speech-language communication and thus categorizes nurses as professional voice users. Consequently, there arises a need to document the extent of awareness regarding voice use and its conservation among nursing professionals.

Ohlsson et al.[20] examined the voice use by 10 Swedish female nurses working in an intensive care unit with mean age of 31.5 years using voice accumulator. The results showed that the mean fundamental frequency was higher on both the days (day 1: 234 Hz; day 2: 235 Hz) for nurses when compared with the speech pathologist (day 1: 216 Hz; day 2: 219 Hz). However, the percent phonation time was lesser on both the days (day 1: 5.4%; day 2: 5.3%) for nurses compared with the speech pathologist (day 1: 6.6%; day 2: 6.9). The decrease in fundamental frequency among speech pathologists was due to the extensive voice training received when compared with nurses who did not undergo any form of voice training. The authors reported that the extensive use of voice by nurses were in the following activities, such as distributing medicines, attending telephone calls, watch duty, providing instructions during testing (e.g. electrocardiogram), during tea/coffee break, lunch time with colleagues, and so on.

Buekers et al.[21] investigated the vocal loading in nine different professional voice user groups including nurses. Self-developed voice accumulator was used to gather the information about use of voice over 12 h. The device registered the intensity and duration of phonation while recording. Among the total duration of the recording (47 h 49 min) of seven nurses who participated in the study, the speaking level above 78–84 dB (A) at work was reported to be 8% and above 84–90 dB (A) was found to be 5%. This study showed that according to the ISO guidelines, over 13% of nurses were in the habit of using loud to screaming voice that is beyond the appropriate voice level such as regular or relaxed voice.

Sala et al.[22] evaluated the vocal loading among day-care center teachers. They compared the speaking duration and intensity level of speaking between 51-day-care center teachers with 25 hospital nurses in Finland. The speaking time, speech levels, and background noise levels in the working environment of both participants were measured. The authors found that the average speaking time of nurses was 28 ± 12% (min 6% and max 50%) during the working day. Further, the authors reported that the average speech level of nurses was 72 ± 2.7 dB (LAeq.0.3 m) and 13% of the time the nurses used a raised voice level (76–81 dB). The authors added that 2% of nurses used loud voice at work (82–87 dB).

Boltežar and Šereg Bahar[23] checked the prevalence of voice disorders and risk factors of six different occupations in Slovenia. It was a meta-analysis study in which the authors considered six Slovenian studies in which one of the study was on nurses.[24] The study included 106 nurses (9 male and 97 female nurses) with the mean age of 42.6 years and the study used a questionnaire to document the voice problems. It revealed that 88.7% of the nurses reported to have at least voice disorders once in their career. Seventy percent of them reported that the common cause of voice problem was vocal load and respiratory tract infection. Results revealed that the nurses were exposed to loud speaking (52% of them), shouting frequently (16% of them), frequent throat-clearing (37% of them), and heartburn and acid regurgitation (28% of them) at work. Only 30% of the nurses reported that they could avail rest during voice problem and remaining 70% of them reported that they continued to work even in the presence of vocal difficulties without any rest. Fourteen percent of them reported to miss work because of voice problem. The authors highlighted that nearly 11% of the nurses received instructions about voice care and remaining 88% of them did not know about voice care procedures.

The above findings show that nurses do extensively employ their voice at work by interacting with doctors, sick patients, attendants, and colleagues. Further, the nurses were also exposed to loud talking which is beyond the quiet speech scenario, increasing the risk of nursing practitioners developing voice problems in the long run.

Sensitization programs are always advantageous as they aim at quick dissemination of important information to a large target group, especially the preventive guidelines regarding certain disorders, diseases, etc. In voice pedagogy, it is a practice-conducting sensitization program to orient participants (both professional and non-professionals) about measures to conserve voice and maintain a healthy voice for personal and occupational needs. These are sets of “do and don’t” about regular voice use and are referred to as vocal hygiene tips. Vocal hygiene tips are best practices of voice production that when followed regularly could help reduce the frequent occurrences of voice problems in speakers.

An example would be a speaker who is in the regular habit of talking loudly, thereby straining and harming the embedded, delicate, and versatile vocal mechanism, the larynx. Such a habit is noted as a vocally abusive behavior. The best practice here will be to monitor the speaking loudness levels and to avoid speaking at full volume. Information will be imparted to the speaker: he/she will be assisted in identifying speaking instances in which full volume is used and suggestions for safe and conducive alternatives to loudness speaking will be conveyed, such as “speaking slowly and clearly, facing the listener/s, exaggerated articulation” to suit the speaking situation/s, listeners’ needs, so forth.

Chan[25] analyzed the efficacy of vocal hygiene education program for kindergarten teachers. Twenty-five female teachers attended a workshop in which the concepts and knowledge of vocal abuse and vocal hygiene were instructed. The vocal hygiene education program included lectures and discussion times and it lasted for 1.5 h. The topics covered by the authors in the vocal hygiene education program were (1) explanation of normal vocal mechanism and laryngeal pathology, (2) explanation of vocal abuses and their consequences (Don’ts), (3) healthy voice use (Do’s), and (4) strategies to maintain classroom order without abusing the voice. The author reported a significant voice improvement in acoustic and electroglottographic parameters after practicing the vocal hygiene tips for a duration of 2 months.

Hence, the present study made an attempt to educate the nursing trainees on voice conservation and to determine the short-term effect of the vocal hygiene education program in them. Also, indirect voice therapy techniques are often focussed on the premise that improper phonatory behavior is a symptom of excessive voice demands, abusive behaviors are harmful to the voice, and/or lack of awareness of safe and healthy voice production. The indirect approach often suggests that the handling of these precipitating, predisposing, and perpetuating components would result in patients’ voice restored to normal or prevent from voice problems occurrence. The indirect voice therapy method (vocal hygiene education) has been shown to improve voice quality in patients with non-organic voice disorders.[12]

There is lack of systematic research to show the short-term effect of such vocal hygiene programs in Indian context on occupational voice users, particularly among prospective nurses. The present study attempts to reduce this gap.

Specific objective

This program was part of the regular orientation/sensitization programs held for different groups of professional voice users: singers, actors, and teachers (both professionals and trainees). Here an attempt was made to include one of the non-vocal professionals, that is, nurses,[26] and to understand the general awareness they possessed about voice production and voice care and conservation. An attempt was made to evaluate the effectiveness of “Voice Care and Conservation” sensitization program for nursing trainees from a local college. The supposition was that improved performance after the conclusion of the sensitization program indicates increased awareness about voice care and voice conservation. Also, this study did not intend to measure any behavioral changes because of vocal hygiene lectures. The hypothesis of the study was that the average percentage correct responses of the nursing trainees who have undergone the structured sensitization program regarding voice conservation and voice care will be significantly higher than their pre-test awareness scores.

 Materials and Methods


One-day sensitization program on Vocal Hygiene and Voice Conservation was conducted to the nursing trainees from a local professional college in the city who were on an “educational visit” as part of their curricular requirement. Ninety-two participants (86 trainees and 6 faculty members) pursuing their final year of the academic degree program took part in the program. The participants took a tour of the institute including the department with the state-of the-art facilities dedicated for voice and speech assessment and management.

Informed consent

Informed consent was obtained from all the participants after explaining the objectives of the study. The study was approved by the AIISH Ethics Committee (AEC) and conformed to the Ethical Guidelines for BioBehavioral Research Involving Human Subjects.



A questionnaire developed by Rajasudhakar et al.[8] shown in Appendix 1 was used in the present study. The questionnaire consisted of 10 questions under 4 sections: (i) demographic data, (ii) Section A—questions related to anatomy and physiology of voice production, (iii) Section B—questions related to causes of the voice disorders, and (iv) Section C—questions related to preventive voice care. One question was open-ended and all the remaining nine were closed-ended questions with provisions for one option from multiple-choice answers.

The study consisted of three phases.

Phase 1: Pre-test: Administration of questionnaire [Appendix 1] prior to the commencement of orientation/sensitization lectures; Phase 2: orientation/sensitization lectures; Phase 3: post-test: administration of questionnaire [Appendix 1] after the conclusion of orientation lectures.


The sensitization program took place in the institute auditorium with provisions for smart classroom set-up. In Phase 1, participants were distributed with a printed questionnaire within the first 15 min after reporting to the venue. They were instructed to complete the questionnaire by choosing the appropriate answer from the given multiple choices. Time duration of 10 min was provided for completion of the questionnaire. The completed questionnaires were collected from all the participants after 10 min ensuring completion of the same. This was followed by the comprehensive lecture presentations (Phase 2). Phase 2 involved two successive lectures by an experienced faculty having expertise in “voice sciences and pathology” on (a) anatomy and physiology of voice and common causes of voice disorders and (b) voice care and vocal hygiene for voice conservation. Each session lasted for a duration of 40 min and was delivered through audio-visual presentation along with the demonstrations. The lectures were simplified and tailor-made to suit the participants and delivered in English language with explanations in the local language wherever required for easy and quick comprehension of the participants. The first lecture covered a brief overview of voice production mechanism, common causes for voice problems, and the risk factors. The second lecture session highlighted on frequent and common habits of voice abuse/misuse, importance of voice conservation, the vocal hygiene tips for voice conservation and voice care, and the do’s and don’ts guidelines for effective voice use. After the conclusion of each lecture session, participants were allowed time for questions and appropriate answers were provided and clarification of doubts was ensured by the faculty experts. The interaction lasted for a maximum of 15 min each after the lecture sessions.

After the completion of the two lectures, the participants were provided with the same printed questionnaires as in Phase 1. Again 10 min time duration was provided for the completion of the questionnaires, and this formed the Phase 3. The completed questionnaires were collected from all the participants.

Analysis of responses

Responses of the participants were analyzed individually and separately for Phase 1 pre- and Phase 3 post-test. Each correct response was awarded “one” mark and incorrect answer was scored as “zero.” The scores were compiled and then the number of correct responses was converted to percentages for Phases 1 and 3. Comparisons were made between the percent correct responses across Phase 1 and Phase 3 for the effectiveness of the sensitization program through improved performance as seen from increased percent correct responses.

Statistical analyses

R software (version 2.9.1) was employed for statistical analyses. The percent correct responses for each question were compared for all the participants across Phase 1 pre- and Phase 3 post-test conditions. The paired t-test was used to obtain significance for all questions across Phases 1 and 3 and the McNemar test was used to compare the significance for each question across the two phases (Phases 1 and 3).


Average improvement in overall responses as percent correct scores across Phases 1 and 3 (pre- and post-test, respectively) is represented in [Figure 1], in which the pre-test correct response was 77.41% and the post-test correct response was 91.46%, respectively. The details are discussed as follows: six out of nine questions had a significant positive difference, that is, the participants obtained higher percent scores in Phase 3. Question 4 had a significant difference but negatively indicating poorer scores by the participants in Phase 3 compared with Phase 1. Question 9 obtained a complete score in both Phases 1 and 3 (pre- and post-conditions, respectively). Two questions (Question 1 and Question 6) had no significant difference. The paired t-test revealed a significant increase in scores from pre-test to post-test with P-value of less than 0.01. The results are depicted in [Table 1] and [Table 2]. [Table 1] represents the percentage correct responses for each question for all the participants, and [Table 2] shows the results of χ2 for individual questions at P-value of less than 0.05.{Figure 1} {Table 1} {Table 2}


Based on the results obtained, the hypothesis indicates that the effect of sensitization program on voice conservation and voice care is accepted. [Figure 1] reveals an improvement in percentages of correct response scores in Phase 3 that followed the two lecture sessions.

Section A: Responses to the questions related to anatomy and physiology of voice production

All the questions had an increase in percentage response except one question (Question 4) which was regarding the structures responsible for modification of voice, which had a reduction in percentage of correct response. During the pre-test, 94% of the participants responded that “throat and mouth” are responsible for modification of voice, whereas only 65% of the participants responded correctly during post-test evaluation. The remaining 35% had selected “lungs and trachea” as voice modifiers. The reduction in percent correct response could be attributed to the emphasis given on the role of larynx and vocal folds as the structures responsible for converting steady stream of pulmonary air into puffs/pulses for creation of voice. This specific explanation regarding the actual function of the vibratory structure led to the participants being confused and undermining the actions of the resonatory and articulatory system in modification of the laryngeal tone. Such specific explanation delineating the actions of the individual subsystems of the speech mechanism could have resulted in the participants selecting a wrong choice as answer after lecture. The increase in response for Question 1 had no statistical significance as it achieved 100% in the post-test compared with 98.87% in the pre-test.

Section B: Responses to the questions related to causes of the voice disorders

The increased responses in Phase 3 were significant for Questions 7 and 8 indicating a raise in awareness of main causes for voice disorders and that severe cough and frequent throat-clearing damages voice. There was an increase in percentage correct response for Question 6; however, it did not reach statistical significance. The results suggest that lectures on causes for voice problems, risk factors, and sources of voice abuse/misuse improved the awareness on causative factors.

Section C: Responses to the questions related to preventive voice care

The responses obtained in Phase 1 for Question 9 indicated that the participants were aware about the professionals responsible for management of voice/speech problems as speech therapists. The responses remained same in Phase 3 with 100% scores. The scores for Question 10 increased from 75.28% (pre-test) to 95.5% (post-test), indicating enhanced understanding on the use of gestures or non-vocal sounds as an alternative to vocal abuse/misuse.

These results found consensus with Boominathan et al.,[7] wherein an increase of 9% in the post-test responses of school teachers was reported. Duffy and Hazlett[6] stated significant improvement in multi-dimensional voice outcome of teachers who attended the sessions compared with those teachers who did not attend the sensitization program. The findings of the current study also concur with the findings of a few other studies,[6],[7],[8] which reported enriched performance post-sensitization programs.

Further, the results, in general, indicated a positive change in the performance of the participants across Phases 1 and 3, revealing the fact that they benefitted from the program. The improved percent scores in Phase 3 for most questions could be a feedback of the improved understanding of the participants about the voice production mechanism, common voice problems, and usefulness of regular practice of voice conversation and vocal hygiene tips.


The prospective nurses were included for the study as nurses are a link between the doctors and patients and hence a significant member in a medical team. It is imperative to sensitize future-to-be-professionals so that safe-guarding voice begins at the initial stages of their careers. Consequently, these hygiene habits could help them conserve healthy voice for a long period of time for better service delivery to the needy as most communication is voice-dependent. Improved percent response scores of the participants in the post-test implied enhanced knowledge about voice production mechanism, common voice problems, and importance of conservation of voice and its care. Such programs could be a successful means for propagation of preventive guidelines to professional voice users at large, helping in reducing the occurrence of voice problems. Incorporation of such sensitization programs in the curriculum of different groups of professional voice users will benefit budding professionals to gain insight about voice use and its care and conservation. The sensitization program in the current study was a first program that targeted the nursing trainees. The demographic information of the participants was not detailed. The participants’ immediate short-term memory effects were assessed in the present study, but the long-term impacts and practices in daily life were not evaluated. The present study only included a few voice care domains/topics in the questionnaire; however, other voice care areas/domains, such as non-vocal practices, diet, water intake, and patient handling in hospitals, ought to be included to understand the vocal demands and difficulties faced by the nurses in professional duties which may help in understanding and identifying areas of concern with regard to voice use as nurses are the ignored group among the professional voice users. Future studies could aim to investigate awareness and vocal hygiene practices in nurses working in different set-ups.

In conclusion, awareness of vocal hygiene for nurses will help them monitor and conserve their voice usage for better vocal health. It is possible that they may use their newly obtained knowledge gained during their careers.

 Lessons for Practice

Knowledge about conservation of voice is important for all, especially the professional voice users.

Orientation programs help disseminate information in a short span of time across a wide audience.

Consequently, such programs may serve as a source to reduce occurrence of voice problems in professional and non-professional voice users.


The authors extend their gratitude to all the participants, the Director, AIISH, Mysuru and University of Mysore, Mysuru.

Financial support and sponsorship

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Conflicts of interest

The authors do not have any conflicts of interest to declare.

Authors’ contributors

K. Y.: Concept, design, verification of data analysis, manuscript editing, manuscript review, and overall responsibility for the integrity of the work.

R. R.: Literature search, data acquisition, data analysis, manuscript preparation.

S. L.: Design, literature search, verification of data analysis, and manuscript review.

Appendix 1

Professional Voice Care Unit (Department of Speech-Language Sciences)

Orientation Programme for Prospective Professional Voice Users on “Conservation of Voice”

Name: College:

Class: Date:


Please answer all the questions.

Section A

1. ___________ is very important for voice production

(a. Breathing b. Eating c. Bathing)

2. Voice box is also called as ________________

3. The vibrating structure responsible for voice production is _______

(a. Vocal folds b. Lips c. Aryepiglottic folds)

4. Voice is modified by ___________

(a. Lungs and trachea b. Stomach and liver c. Throat and mouth)

5. The pitch/tone used by an adult male is __________

(a. Mid b. Low c. High)

Section B

6. Voice problems are very common among, ___________

(a. Accountant b. School-teachers c. Librarians)

7. What are the main causes for voice disorders? Tick (✓) the appropriate answer.

(a. Screaming; b. Smoking; c. Running)

8. Severe cough and frequent throat clearing lead to _____________ voice

(a. Improve b. Damage c. Preserve).

Section C

9. The professional who is responsible for improving voice/speech is __________

(a. Physiotherapist b. Occupational therapist c. Speech therapist)

10. Use of gestures or non-vocal sounds can ___________ the voice.

(a. Protect b. Damage c. Harm)


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