Seasonal variation in urinary stone presentation is well described in the literature. However, previous studies have some limitations. To explore overall cumulative exposure-response and the heterogeneity in the relationships between daily meteorological factors and urolithiasis incidence in 6 major Korean cities, we analyzed data on 687,833 urolithiasis patients from 2009 to 2013 for 6 large c...

In population studies on aging, the data on genetic markers are often collected for individuals from different age groups. The purpose of such studies is to identify, by comparison of the frequencies of selected genotypes, "longevity" or "frailty" genes in the oldest and in younger groups of individuals. To address questions about more-complicated aspects of genetic influence on longevity, addi...

BACKGROUND Despite the highly selective admission processes utilised by medical schools, a significant cohort of medical students still face academic difficulties and are at a higher risk of delayed graduation or outright dismissal. METHODS This study used survival analysis to identify the non-academic and academic risk factors (and their relative risks) associated with academic difficulty at...

OBJECTIVES To assess the degree of relationship among individuals with hemangiomas and to evaluate the relative risk (RR) for family members of individuals with hemangiomas. DESIGN Retrospective case-control study. SETTING Utah Population Database. PARTICIPANTS Data sets of individuals of different ages with International Classification of Diseases, Ninth Revision (ICD-9) codes for hemang...

BACKGROUND Sharps injuries in health care personnel still represent a significant problem worldwide. Many studies show a reduction in sharps injuries following the introduction and use of different protection devices, but few studies focus on the role of training programmes in the prevention of such injuries. AIMS To analyse the influence of training programmes on sharps injuries in health ca...

OBJECTIVE The performance of association tests based on case-control or case-parents substudy alone can be improved by jointly using genetic data from two substudies. However, genetic data from different sources may not be combinable due to population stratification. We propose a two-stage association test based on using combinability tests in stage 1 and association tests in stage 2. METHODS...

Since the late 1980s, with the first identification of individuals who were exposed to human immunodeficiency virus type 1 (HIV-1) yet remained uninfected, or "HIV-1-resistant" individuals, a large number of cohorts that include HIV-exposed seronegative (HESN) subjects have been identified globally for the purpose of investigating the genetic, immunologic, and environmental factors that may hel...

STUDY OBJECTIVES To determine the risk of asthma among patients with occupationally induced rhinitis. DESIGN Patients with confirmed occupational rhinitis were followed for asthma incidence through register linkage. Patients with other occupational diseases were used as a reference population. SUBJECTS Patients entered into the Finnish Register of Occupational Diseases in from 1988 to 1999 ...

PURPOSE To evaluate the clinical and economic impact of prophylactic administration of intracameral cefuroxime on cataract surgery. SETTING Hospital Universitario Fundación Alcorcón, Madrid, Spain. DESIGN Quasi-experimental study with before and after analysis. METHODS The evolution of the cumulative incidence of endophthalmitis before and after (October 2005) administration of intracamer...

The authors investigated whether there was a decline in infants sleeping prone and other modifiable risk factors for sudden infant death syndrome (SIDS) in Germany, where, as in some other countries, no nationwide intervention campaign against the prone sleeping position had been initiated. Data were obtained from parents by mailed questionnaires in two cross-sectional studies in 1991 (n = 3,33...