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Prevalence Difference (prevalence + difference)

Distribution by Scientific Domains
Medical Sciences83%

Selected Abstracts

Changing prevalence of asthma in Taiwanese adolescents: two surveys 6 years apart

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 2 2005
Yung-Ling Lee
This study compared the prevalence of asthma among Taiwanese adolescents with individual-level risk factors and municipal-level air pollution and meteorology data to determine whether changes in these factors could explain the observed change in prevalence. We conducted two national surveys of respiratory illness and symptoms in Taiwanese middle-school students in 1995,96 and 2001. The effects of personal and environmental factors were assessed and temporal changes of outdoor monitoring data were also compared with asthma prevalence difference. A total of 44,104 children from the 1995,96 survey and 11,048 children from the 2001 survey attended schools located within 1 km of 22 monitoring stations. Lifetime prevalences of physician-diagnosed and questionnaire-determined asthma increased during this period. After adjustment for potential risk factors, the prevalence differences were statistically unchanged. Although parental education level contributed most, changes in investigated personal and environmental factors might not explain the observed changes in asthma prevalence. Municipalities with higher temperature increase were significantly associated with prevalence difference in questionnaire-determined asthma. We concluded that correlates of the investigated individual-level factors, which have changed over time, still underlie changes in asthma prevalence. Increasing temperature might be the main reason for the rising trends of asthma in Taiwanese adolescents. [source]

Increasing prevalence of atopic eczema in Taiwanese adolescents from 1995 to 2001

CLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2007
Y.-L. Lee
Summary Background The prevalence of atopic eczema in adolescents has recently been reported as increasing in many countries, a phenomenon yet to be fully explained. This study compared the prevalence of atopic eczema among Taiwanese adolescents with individual-level risk factors and community-level data of temperature, relative humidity, and air pollutants to determine whether changes in these factors could explain the observed change in prevalence. Methods We conducted two nationwide, cross-sectional surveys of atopic illness and symptoms among Taiwanese 12,15-year-old schoolchildren in 1995,1996 and 2001. The effects of personal and environmental factors were assessed and temporal changes of outdoor monitoring data were also compared with the prevalence difference of atopic eczema. Results A total of 42 919 adolescents from the 1995 to 1996 survey and 10 215 adolescents from the 2001 survey attended schools located within 1 km of 22 monitoring stations. The 12-month prevalence of atopic eczema increased significantly during this period [adjusted prevalence ratio (PR)=1.43, 95% confidence interval (CI) 1.21,1.70 in boys; PR=1.77, 95% CI 1.49,2.10 in girls]. After adjustment for potential risk factors, the prevalence differences were statistically unchanged. Although parental education level contributed the most, changes in personal and environmental factors might not explain the observed prevalence increases of atopic eczema. Temporal change in the relative humidity was significantly associated with prevalence increase among boys but its contribution was also small. Conclusion Correlates of the investigated risk factors that have changed over time still underlie the prevalence increases of atopic eczema in Taiwanese adolescents. The exact reasons for the rising trends remain to be elucidated. [source]

Changing prevalence of asthma in Taiwanese adolescents: two surveys 6 years apart

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 2 2005
Yung-Ling Lee
This study compared the prevalence of asthma among Taiwanese adolescents with individual-level risk factors and municipal-level air pollution and meteorology data to determine whether changes in these factors could explain the observed change in prevalence. We conducted two national surveys of respiratory illness and symptoms in Taiwanese middle-school students in 1995,96 and 2001. The effects of personal and environmental factors were assessed and temporal changes of outdoor monitoring data were also compared with asthma prevalence difference. A total of 44,104 children from the 1995,96 survey and 11,048 children from the 2001 survey attended schools located within 1 km of 22 monitoring stations. Lifetime prevalences of physician-diagnosed and questionnaire-determined asthma increased during this period. After adjustment for potential risk factors, the prevalence differences were statistically unchanged. Although parental education level contributed most, changes in investigated personal and environmental factors might not explain the observed changes in asthma prevalence. Municipalities with higher temperature increase were significantly associated with prevalence difference in questionnaire-determined asthma. We concluded that correlates of the investigated individual-level factors, which have changed over time, still underlie changes in asthma prevalence. Increasing temperature might be the main reason for the rising trends of asthma in Taiwanese adolescents. [source]

Differential risks to males and females for congenital malformations among 2.5 million California births, 1989,1997

BIRTH DEFECTS RESEARCH, Issue 12 2003
Gary M. Shaw
Abstract BACKGROUND Although many studies have observed variations in the prevalence of specific malformations by sex, there is a lack of population-based data on potential malformation prevalence differences by sex at birth. METHODS Our objective was to explore differences in the prevalence of structural congenital malformation phenotypes between sexes in a California population of 2.5 million live- and stillbirths, using data from a population-based active surveillance system. Ascertainment was performed among offspring of California women who delivered in nonmilitary hospitals during the period of 1989,1997. Malformations were grouped according to the four-digit malformation codes of the British Pediatric Association. RESULTS Overall, 32,619 males and 21,835 females were considered to have structural congenital malformations, with prevalences of 2.52% and 1.76%, respectively. Thus, males demonstrated a malformation prevalence that was 22% higher than that in females. Using a criterion of a 40% increase or decrease in the relative risk for males, increased risks for 15 and decreased risks for 17 specific malformation categories were observed. Increased risks were associated with most organ systems, with the notable exception of the nervous system (increased risks for nervous system malformations were observed among female births). Risks were not substantially influenced by adjusting for maternal age, race/ethnicity, parity, or education. CONCLUSIONS Our observations extend the relatively few studies that have investigated differential prevalences of a large number of specific structural malformations between male and female births. Birth Defects Research (Part A) 67:000,000, 2003. © 2003 Wiley-Liss, Inc. [source]

Increasing prevalence of atopic eczema in Taiwanese adolescents from 1995 to 2001

CLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2007
Y.-L. Lee
Summary Background The prevalence of atopic eczema in adolescents has recently been reported as increasing in many countries, a phenomenon yet to be fully explained. This study compared the prevalence of atopic eczema among Taiwanese adolescents with individual-level risk factors and community-level data of temperature, relative humidity, and air pollutants to determine whether changes in these factors could explain the observed change in prevalence. Methods We conducted two nationwide, cross-sectional surveys of atopic illness and symptoms among Taiwanese 12,15-year-old schoolchildren in 1995,1996 and 2001. The effects of personal and environmental factors were assessed and temporal changes of outdoor monitoring data were also compared with the prevalence difference of atopic eczema. Results A total of 42 919 adolescents from the 1995 to 1996 survey and 10 215 adolescents from the 2001 survey attended schools located within 1 km of 22 monitoring stations. The 12-month prevalence of atopic eczema increased significantly during this period [adjusted prevalence ratio (PR)=1.43, 95% confidence interval (CI) 1.21,1.70 in boys; PR=1.77, 95% CI 1.49,2.10 in girls]. After adjustment for potential risk factors, the prevalence differences were statistically unchanged. Although parental education level contributed the most, changes in personal and environmental factors might not explain the observed prevalence increases of atopic eczema. Temporal change in the relative humidity was significantly associated with prevalence increase among boys but its contribution was also small. Conclusion Correlates of the investigated risk factors that have changed over time still underlie the prevalence increases of atopic eczema in Taiwanese adolescents. The exact reasons for the rising trends remain to be elucidated. [source]