A copula model for marked point processes

The final publication (Diao, Liqun, Richard J. Cook, and Ker-Ai Lee. (2013) A copula model for marked point processes. Lifetime Data Analysis, 19(4): 463-489) is available at Springer via http://dx.doi.org/10.1007/s10985-013-9259-3Many chronic diseases feature recurring clinically important events. In addition, however, there often exists a random variable which is realized upon the occurrence of each event reflecting the severity of the event, a cost associated with it, or possibly a short term response indicating the effect of a therapeutic intervention. We describe a novel model for a marked point process which incorporates a dependence between continuous marks and the event process through the use of a copula function. The copula formulation ensures that event times can be modeled by any intensity function for point processes, and any multivariate model can be specified for the continuous marks. The relative efficiency of joint versus separate analyses of the event times and the marks is examined through simulation under random censoring. An application to data from a recent trial in transfusion medicine is given for illustration.Natural Sciences and Engineering Research Council of Canada (RGPIN 155849); Canadian Institutes for Health Research (FRN 13887); Canada Research Chair (Tier 1) – CIHR funded (950-226626

Correlates of receiving recommended adolescent vaccines among adolescent females in North Carolina

Background: Immunization is a successful and cost-effective method for preventing disease, yet many adolescents do not receive recommended vaccines. We assessed correlates of uptake of three vaccines (tetanus booster, meningococcal and human papillomavirus [HPV] vaccines) recommended for adolescent females. Results: Only 17% of parents indicated their daughters had received all three vaccines. Eighty-seven percent of parents indicated their daughters had received tetanus booster vaccine, 36% reported vaccination against meningococcal disease and 36% reported HPV vaccine initiation. Daughters aged 13–15 years (OR = 1.70, 95% CI: 1.09–2.64) or 16–20 years (OR = 2.28, 95% CI: 1.51–3.44) had received a greater number of these vaccines compared to daughters aged 11–12 years. Daughters who had preventive care visits in the last year (OR = 4.81, 95% CI: 3.14–7.34) or whose parents had at least some college education (OR = 1.90, 95% CI: 1.29–2.80) had also received a greater number of these vaccines. Methods: We examined cross-sectional data from 647 parents of 11–20 year-old females from North Carolina who completed the Carolina HPV Immunization Measurement and Evaluation (CHIME) Project follow-up survey in late 2008. Analyses used ordinal and binary logistic regression. Conclusions: Few daughters, particularly 11–12 years olds, had received all three vaccines recommended for adolescent females. Ensuring annual preventive care visits and increasing concomitant administration of adolescent vaccines may help increase vaccine coverage

Chemical and biochemical sensing applications of microstructured optical fiber-based systems

This paper provides an up-to-date overview on\ud the use of microstructured optical fibers (MOFs) in chemical\ud sensing during the last ten years, more specifically, applications\ud in liquid media including the use of solid-core photonic\ud crystal fibers, hollow-core PCFs and other MOFs and related\ud microstructures. To this aim, a classification of different types\ud of fiber-based chemical sensors is first made, followed by a\ud description of the most important MOFs and their operation\ud principles in chemical sensing. Then, studies on the use of\ud MOFs in fluorescence, Raman and SERS detection among\ud other detection principles are discussed. Finally, literature including\ud the implementation of these microstructures in homemade\ud and commercial analytical equipment is summarized.\ud This review intends not only to give a current perspective on\ud the use of MOFs and microstructures in chemical sensing, but\ud also to make an approach between the fields of optical fiber and\ud analytical chemistry, in order to understand the basic principles\ud of operation in this promising frontier of knowledg