• Korean Journal of Cognitive Science
• /
• v.32 no.3
• /
• pp.117-139
• /
• 2021

The way of change detection in which presence of a different item is determined between memory and test arrays with a brief in-between time interval resembles how visual search is done considering that the different item is searched upon the onset of a test array being compared against the items in memory. According to the resemblance, the present study examined whether varying the probability of change occurrence in a visual short-term memory-based change detection task can influence the aspect of response-decision making (i.e., change prevalence effect). The simple-feature change detection task in the study consisted of a set of four colored boxes followed by another set of four colored boxes between which the participants determined presence or absence of a color change from one box to the other. The change prevalence was varied to 20, 50, or 80% in terms of change occurrences in total trials, and their change detection errors, detection sensitivity, and their subsequent RTs were analyzed. The analyses revealed that as the change prevalence increased, false alarms became more frequent while misses became less frequent, along with delayed correct-rejection responses. The observed change prevalence effect looks very similar to the target prevalence effect varying according to probability of target occurrence in visual search tasks, indicating that the background principles deriving these two effects may resemble each other.

• Tuberculosis and Respiratory Diseases
• /
• v.80 no.3
• /
• pp.226-229
• /
• 2017

Chronic obstructive pulmonary disease (COPD) had been considered the only major disease that is continuing to increase in prevalence. There were a few studies about the change of the prevalence of COPD, which showed the prevalence of COPD did not increase. In this review, we report on the trends in the prevalence of COPD in Korea using the data from Korea National Health and Nutrition Examination Survey (KNHANES). The prevalence of COPD in 2015 was 13.4% (male, 21.6%; female, 5.8%). The prevalence of COPD did not change much, which ranged from 13.1% to 14.6% during the period from 2010 to 2015. Among the subjects found to have COPD by spirometry, only 2.8% had been diagnosed as COPD by physicians during the period from 2011 and 2015. In conclusion, the prevalence of COPD did not change significantly during the period from 2010 to 2015. And most COPD patients still had not been diagnosed by physicians and consequently had not been treated appropriately.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.31 no.4
• /
• pp.214-224
• /
• 2020

Objectives: This study aimed to examine the trend in diagnostic prevalence of psychiatric disorders in children and adolescents. Methods: Individuals aged 0-18 years were included in the study based on the National Health Insurance Claims Data. To investigate the trends in diagnosis and diagnostic prevalence of psychiatric disorders reflecting the decrease in the birth rate, data were analyzed from 2010 as a reference year to 2015. Results: The number of patients diagnosed with psychiatric disorder decreased annually, from 23,412 on 2010 to 18,821 on 2015. The most common disorder was hyperkinetic disorder in male and depressive episode in female. Although there was no significant change in overall diagnostic prevalence rate of psychiatric disorders, age groups <10 years and some disorders had significant changes in prevalence rate. This study classified the diagnostic prevalence by age into two unique patterns: group in which the diagnosis rate increases with age and group in which the diagnosis rate peaks at a certain age and then decreases. Conclusion: Diagnostic prevalence of psychiatric disorders was different according to age and sex. These patterns should be reflected in the formulation of policies related to mental health and in medical practice for pediatric patients. It is urgent to identify how these patterns change in young adults.

• Clinical and Experimental Pediatrics
• /
• v.64 no.2
• /
• pp.86-92
• /
• 2021

Background: Anemia is an important health problem affecting approximately 25% of the global population. Although its prevalence is decreasing worldwide, few studies have examined the prevalence of anemia in Korean adolescents. Purpose: This study aimed to determine the prevalence of anemia in Korean adolescents over the past 21 years using data from the Korea National Health and Nutrition Examination Survey. Methods: We investigated the prevalence of anemia in adolescents aged 10-18 years for the period 1998-2018 according to sex, age, residential area, and household income. The effects of menarche age and menstruation were examined in female adolescents for the period 2001-2018. Results: Among the total 11,782 participants, the weighted prevalence of anemia was 4.0%. The prevalence of anemia in male participants significantly decreased (from 3.0% to 0.5%, P<0.001), whereas that in female participants did not change significantly over time (from 7.9% to 8.5%, P=0.054). The average age at menarche was 12.4±0.0 years; the prevalence of anemia in females increased from age 13 years onward. Multivariate analysis revealed that anemia was more common in female than male participants (odds ratio [OR], 9.88; 95% confidence interval [CI], 7.19-13.57; P<0.001). In female adolescents, the prevalence of anemia increased with age (OR, 1.26; 95% CI, 1.15-1.38, P<0.001) and was 3.6 times higher after than before menarche (OR, 3.65; 95% CI, 2.21-6.05, P<0.001). Conclusion: Over the 21-year study period, the prevalence of anemia decreased among male adolescents but did not change in female adolescents. In female adolescents, age and menarche were identified as significant risk factors that require continued attention.

• Journal of Korean Academy of Rural Health Nursing
• /
• v.4 no.1
• /
• pp.5-12
• /
• 2009

Purpose: The purpose of this study was to describe the prevalence of clonorchiais and analyze the knowledge level and intention of the participants to change their behavior related to clonorchiais. Method: The participants were 514 people from 7 community health posts along the Geum River. The formalin-esther sedimentation technique was used to detect the Clonorchis Sinensis (CS) eggs and a questionnaire for data on related factors. The study was carried on from December 2008 to January 2009. Results: The prevalence of CS averaged 9.3%, with a range from 0% to 24.6%. The significant factors were sex, habit of eating raw fish, and habit related to smoking and alcohol consumption. The level of knowledge was not high and not significantly different between the CS positive group and CS negative group. Intention to change their habits of eating raw fish showed various stages of change and attitudes to raw fish eating habit of others were not positive. Conclusions: These results suggest that a CS control program needs to be developed by community health services in the Geum River area to decrease the prevalence of clonorchiais.

• Parasites, Hosts and Diseases
• /
• v.57 no.6
• /
• pp.601-605
• /
• 2019

As we learn more about parasites in ancient civilizations, data becomes available that can be used to see how infection may change over time. The aim of this study is to assess how common certain intestinal parasites were in China and Korea in the past 2000 years, and make comparisons with prevalence data from the 20th century. This allows us to go on to investigate how and why changes in parasite prevalence may have occurred at different times. Here we show that Chinese liver fluke (Clonorchis sinensis) dropped markedly in prevalence in both Korea and China earlier than did roundworm (Ascaris lumbricoides) and whipworm (Trichuris trichiura). We use historical evidence to determine why this was the case, exploring the role of developing sanitation infrastructure, changing use of human feces as crop fertilizer, development of chemical fertilizers, snail control programs, changing dietary preferences, and governmental public health campaigns during the 20th century.

• Journal of Nutrition and Health
• /
• v.39 no.1
• /
• pp.44-49
• /
• 2006

The aim of this study was to evaluate the body composition difference and obesity prevalence in grade 5 to 8 by gender. A total of 1,333 students, 707 boys and 631 girls, were recruited from one elementary and one middle school in Seoul, Korea. Anthropometric measurements including height, weight, lean body mass, and body fat were assessed. Height and weight were increased by grade, but Body Mass Index (BMI) by grade showed no significant difference among boys. Lean body mass had growth spurt between 7 and 8 grade among boys compared to gradual increase among girls. Overweight and obesity prevalence were higher among elementary schoolers than middle schoolers. Overweight (BMI for age> $85^{th}$ percentile) prevalence was about $44\%$ among $5^{th}$ grade boys compared $29\%$ among same grade girls. These results provided that there were prominent difference regarding body growth and obesity prevalence in gender and grade. Further studies for children and adolescents should be considered their body composition change.

• Journal of Preventive Medicine and Public Health
• /
• v.29 no.3 s.54
• /
• pp.565-577
• /
• 1996

This study was conducted to evaluate the association of work posture with cervical spine abnormality toward 106 microwave-oven assemblers. A self-administered questionnaire was used to obtain a general characteristics and a work history of workers. The posture of neck and shoulder joint of workers were measured with video tape recording and the simple X-ray of cervical spine was checked-up to observe the X-ray abnormality including degenerative change, curvature abnormality, disc space narrowing or disc canal narrowing. The result were as follows. 1. The prevalence of degenerative change among cervicobrachial disorder workers was 44.3% (47 persons), curvature abnormality was 43.4%(46 persons), disc space narrowing was 21.7%(23 persons), and disc canal narrowing was 21.7%(23 persons). 2. The prevalence of degenerative change at cervical spine was increased with the degree of neck flexion(flexed versus neutral, odds ratio [OR]=2.7), the total work posture of neck(mild or severe awkward versus neutral ; OR=1.2, 3.4). 3. The prevalence of degenerative change at cervical spine was increased with the degree of the right shoulder flexion, the heaviness of the materials carried by the right hand and the degree of awkwardness at the total work posture of right shoulder(p<0.05). 4. There was no evidence of association between curvature abnormality, disc space narrowing, disc canal narrowing and work posture. In conclusion the awkward work posture was related with degenerative change of cervical spine among microwave oven assembling workers and the further study in these field must be made to prove the association objectively.

• Journal of Korean Academy of Rural Health Nursing
• /
• v.4 no.2
• /
• pp.87-93
• /
• 2009

Purpose: This study was done to investigate the knowledge, attitude and prevalence status of Clonorchiasis Sinensis (C.S.) for inhabitants in the Nakdong riverside area. Method: Data were collected from December 16, 2008 to January 10, 2009. Participants were 552 people who responded to a questionnaire and had a stool examination. Results: The overall prevalence of C.S. was 13.8%. As for knowledge of C.S., the Clonorchiasis group had a mean score of 10.78 $({\pm}3.54)$ on a 17-point scale compared to a score of 10.58 $({\pm}4.15)$ for the negative group. The intended behavioral change related to risk of infection, according to presence of infection or not, was not significant but the Clonorchiasis group had a greater desire for behavioral change intention than the negative group. Conclusion: These results suggest that prevalence investigation of C.S. in all areas in the Nakdong riverside is needed and indicates that it is necessary to set up persistent and systematic management programs for patient care and prevention of C.S..

• 월간산업보건
• /
• s.227
• /
• pp.56-60
• /
• 2007