Age- and Gender-Related Mean Hearing Threshold in a Highly-Screened Population: The Korean National Health and Nutrition Examination Survey 2010–2012 - Fig 2

<p>Gender difference of the mean hearing threshold in proportion to age at 0.5 kHz (A), 1 kHz (B), 2 kHz (C), 3 kHz (D), 4 kHz (E), and 6 kHz (F) frequencies (highly-screened population, N = 33,011,778 ears). At 0.5 kHz, 1 kHz, and 2 kHz, no difference in the mean threshold level was found between males and females. However, at 3 kHz, 4 kHz, and 6 kHz, the mean threshold levels for males are worse than the levels for females. Among the three frequencies, the most significant difference of the mean threshold level between males and females with the same age occurs at 4 kHz.</p

The four-tone average of 0.5 kHz, 1 kHz, 2 kHz, and 3 kHz (PTA4) (highly-screened population, N = 33,011,778 ears).

<p>Both genders showed similar four-tone average values. However, with increasing age, the gender difference of PTA4 tends to increase. PTA4: four-pure tone average.</p

Box-and-whisker plot (left) combined with mean difference and limit of agreement (LOA, right) for the decibel difference between the threshold at 3 kHz (H3k) and the average of thresholds at 2 kHz and 4 kHz (H24k) according to eight age groups (weighted N = 39,357,497 × 2 ears, age: 12–82 year-old).

<p>The box height is the interquartile range (IQR = Q3 –Q1) of the decibel difference for each age. The thick horizontal line in the box is the median (Q2). Outliers are marked as empty circles below the vertical dotted line from the box (Q1–1.5 IQR) and above the dotted line (Q3 + 1.5 IQR). This boxplot shows that the median and the interquartile range of difference between H3k and H24k are distributed around zero, irrespective of age group. Therefore, it can be interpreted that H3k and H24k had very similar mean values in all cases. In addition, the absolute limit of agreement in all age group was very large irrespective of age. dBHL: decibel hearing level; H2k: threshold at 2 kHz; H3k: threshold at 3 kHz; H4k: threshold at 4 kHz; IQR: interquartile range; Q1: first quartile (25 percentile); Q2: second quartile (median, 50 percentile); Q3: third quartile (75 percentile).</p

Mean Hearing Threshold Level and Standard Deviation as a Function of Gender, Frequency, and Age Group in a Highly-Screened Population, and Comparison between Mean Thresholds of both Genders (M: F = 15,575,206: 17,436,572, weighted).

<p>Mean Hearing Threshold Level and Standard Deviation as a Function of Gender, Frequency, and Age Group in a Highly-Screened Population, and Comparison between Mean Thresholds of both Genders (M: F = 15,575,206: 17,436,572, weighted).</p

Selection of Participants with Normal Tympanic Membrane and No History of Noise Exposure.

<p>Selection of Participants with Normal Tympanic Membrane and No History of Noise Exposure.</p

Demographic Data of Highly-Screened Participants in the Korea National Health and Nutrition Examination Survey (KNHANES), 2010–2012.

<p>Demographic Data of Highly-Screened Participants in the Korea National Health and Nutrition Examination Survey (KNHANES), 2010–2012.</p

(A) Scatter plot between the threshold at 3 kHz (H3k) and the average of thresholds at 2 kHz and 4 kHz (H24k). (B) Distribution of the difference between H3k and H24k (weighted N = 39,357,497 × 2 ears).

<p>The scatter plot shows a statistically strong correlation between H3k and H24k (R = 0.92, p<0.0001). The predictive linear regression equation was <i>y</i> = –0.6821 + 1.0186<i>x</i> (<i>x</i> = H24k, <i>y</i> = H3k, p<0.0001, R² = 0.849). The difference between the H3k and H24k displays a distribution pattern that is similar to a normal distribution. M: million; dBHL: decibel hearing level.</p

Age- and Gender-Related Mean Hearing Threshold in a Highly-Screened Population: The Korean National Health and Nutrition Examination Survey 2010–2012 - Fig 1

<p><b>Age- and gender-related distribution of participants (unweighted, the left 1st axis) and the corresponding population (weighted, the left 2nd axis)</b>. The blue and red columns show the distribution of 15,606 participants, and the cyan and pink columns represent 33,011,778 members of the Korean population, according to gender and age groups. The proportion of the participants is different from the proportion of the study population. This figure shows the difference between the occupation percentage of the unweighted and the weighted sample numbers, according to age group. If the unweighted design is used for analysis, male participants in their teens, twenties, thirties, forties, and fifties are under-sampled and participants in their sixties, seventies, and eighties are over-sampled. These ratio differences would affect the final outcome. In order to produce unbiased cross-section estimates for the entire Korean population, the specialized statistical technique of complex sampling design, considering survey sample weights and strata, should be utilized. UWt: Unweighted, Wt: Weighted.</p

Demographic data of participants in this study (subset of Korea National Health and Nutrition Examination Survey [KNHANES]).

<p>Demographic data of participants in this study (subset of Korea National Health and Nutrition Examination Survey [KNHANES]).</p

Box-and-whisker plot (left) for the mean difference and limit of agreement (right) of difference between the threshold at 3 kHz (H3k) and the average of thresholds at 2 kHz and 4 kHz (H24k) against the threshold groups. (A) 2 kHz; (B) 3 kHz; (C) 4 kHz; and (D) four-tone (0.5, 1, 2, and 3 kHz) average (weighted N = 39,357,497 × 2 ears).

<p>These graphs show that the degree of hearing thresholds at the three frequencies and at the four-tone average did not affect the distribution of the difference between H3k and H24k. However, the upper and lower limits of agreement are roughly greater than 10 dBHL and less than –10 dBHL, respectively. ※Threshold groups are divided as follows: normal (<26 dBHL), mild (26–40 dBHL), moderate (41–55 dBHL), moderately severe (56–70 dBHL), severe (71–90 dBHL), and profound (>90 dBHL); dBHL: decibel hearing level.</p