Noise sensitivity and its associated factors among the students of Rajshahi City in Bangladesh: A cross-sectional study

Background: Noise pollution is an important environmental problem with far-reaching and unavoidable consequences. The present study aimed to identify noise sensitivity and its associated factors among students of Rajshahi City. Methods: A total of 473 respondents were selected conveniently from five educational institutions in Rajshahi City. Among them, 273 were women, and 200 were men aged 18 to 28 (mean, 22.9). The Bangla version of the Noise Sensitivity Scale was administered to measure the participants' noise sensitivity level. Results: Noise sensitivity varied significantly with sleep duration, anger toward noise polluters, level of noise annoyance

Furthermore, noise sensitivity can negatively impact academic performance and productivity among students.It can also cause physiological arousal, increase stress levels, impair cognitive functions, decrease concentration, and decrease academic achievement. 7,8 le the effects of noise pollution are well-known, the aversion and reaction to noise and a noisy environment is called noise sensitivity. 13It is a psychological trait that determines an individual's subjective noise perceptions and responses, 14 including both the degree of annoyance and physiological arousal. 13ny studies have focused on noise pollution in Bangladesh from engineering and geographical perspectives.However, psychological-based research is limited.Therefore, this study aimed to investigate the noise sensitivity levels and associated factors among students in Rajshahi City, Bangladesh.

Sample
This cross-sectional study was conducted from January to February 2024 among conveniently selected university-level students.The sample size was determined using the formula Z 2 * p * (1-p)/d 2 , where the expected proportion was unknown (p= 0.5) and the desired precision d was 0.05.Although the minimum sample size, using the formula above was 384, we recruited 473 participants.

Data collection
Data were collected in classroom settings using a selfadministered questionnaire with due informed consent.
Participants were first given instructions on completing the questionnaire.During this process, participants were informed about the study's purpose and assured that their participation was anonymous, confidential, and voluntary.After obtaining consent, students completed the questionnaires, which took 15-20 minutes.
The adapted Weinstein Noise Sensitivity Scale-Short Form (WNSS-SF-Bangla Version) (unpublished) consists of 5 items, deriving from the long-form scale, originally coded as items (Item 7: I get annoyed when my neighbours are noisy.Item 8: I get used to most noise without much difficulty.Item 18: I find it hard to relax in a place that's noisy.Item 19: I get mad at people who make noise that keeps me from falling asleep or getting work done.Item 21: I am sensitive to noise).It had 6-point Likert-type scale responses ranging from strongly disagree (coded as 1) to strongly agree (coded as 6).After reversing the number 8 (recode item), the total noise sensitivity score is obtained by summing the five items.Scores on this scale ranged from 6 (lower noise sensitivity) to 30 (higher noise sensitivity).In this study, the unpublished NSS-SF-BV tool was used, which was adapted by the authors and derived from Benfield et al. 14

Statistical analysis
Descriptive analyses were conducted to ascertain the frequencies and percentages of participants' sociodemographic and noise-related characteristics.Multiple linear regression was done to predict the relationship between noise sensitivity and the associated variables.
In the regression analysis, sex, sleep duration, noisepolluted residence, anger at polluters, noise pollution awareness, loud speaking/television volume, and alternative route usage were entered as independent variables in the model, with the noise sensitivity total score as the dependent variable.Statistical significance was determined with an alpha threshold of 0.05.Data analysis was performed using the SPSS version 26.

RESULTS
The study sample included 473 participants, 57.7% women and 76.1% holding bachelor-level qualifications.About 41% resided in rented group accommodations (TABLE 1).We found no statistically significant differences between sexes in terms of noise-sensitive scores.However, participants with lower sleep duration (4-5 hours) had significantly higher noise sensitivity scores compared to those with normal sleep duration (P = 0.04).Those who experienced anger towards polluters also had significantly higher scores (P = 0.002).Additionally, individuals who always used alternative routes to avoid noise-polluted roads reported higher noise sensitivity (P = 0.02), and those with much annoyance due to noise had significantly higher scores (P < 0.001) (TABLE 2).
The regression analysis results indicated that anger at polluters (β = -0.11,P = 0.02) and noise annoyance (β = -0.20,P < 0.001) were significantly associated with noise sensitivity (TABLE 3).Among these, noise annoyance emerged as the strongest predictor in the model.These findings highlight that individual perceptions of noise sensitivity are influenced by multiple factors, underscoring the importance of considering various demographic and behavioural elements in understanding these perceptions (TABLE 3).

DISCUSSION
Noise sensitivity is a personality trait that may predict discomfort and health-related consequences from noise exposure. 15,16 hile noise sensitivity significantly impacts students' sleep duration, annoyance levels, overall well-being, and academic performance, 3  This study demonstrates that noise sensitivity reduces adult sleep duration. 15other finding from the study revealed that anger towards polluters was strongly correlated with increased perceptions of noise sensitivity.A recent study in India also stated that anger at noise polluters and attitudes toward noise pollution are linked. 17milarly, an Ecuadorian study found that noise pollution perceptions affected health, happiness, and life satisfaction. 18The results of these studies align with the present study's findings.Noise sensitivity and its associated factors 3 of 4   The present study also shows that perceptions vary depending on the level of annoyance with noise.Those who experienced extreme annoyance reported higher sensitivity than those who experienced only lower annoyance.This suggests that individual annoyance levels impact the perceived effects of noise pollution.
Studies have demonstrated that an individual's annoyance levels can substantially influence how they perceive the consequences of noise pollution. 13Yu et al. 19 HIGHLIGHTS1.One in five students in Rajshahi city has high noise sensitivity.2.Those with shorter sleep durations have higher noise sensitivity than those with normal sleep durations.3.People who are more annoyed with noise pollution have higher noise sensitivity.

TABLE 3 Linear regression of noise sensitivity on related factors (n=473)
found that physiological and psychological factors can influence tolerance levels.The results indicate that an individual's tolerance levels significantly impact how they perceive noise pollution.Although our study has the limitations of having done in purposively recruited subjects and lacks national representation, it provides an important basis for largescale studies.Various factors, such as sleep duration, anger towards noise polluters, and overall irritation from noise, influence students' noise sensitivity.The findings indicate that students who sleep less and experience higher levels of annoyance due to noise exhibit greater noise sensitivity.This highlights the importance of addressing noise sensitivity issues among students.