Preterm birth: Case definition & guidelines for data collection, analysis, and presentation of immunisation safety data.

Preterm birth is commonly defined as any birth before 37 weeks completed weeks of gestation. An estimated 15 million infants are born preterm globally, disproportionately affecting low and middle income countries (LMIC). It contributes directly to estimated one million neonatal deaths annually and is a significant contributor to childhood morbidity. However, in many clinical settings, the information available to calculate completed weeks of gestation varies widely. Accurate dating of the last menstrual period (LMP), as well as access to clinical and ultrasonographic evaluation are important components of gestational age assessment antenatally. This case definition assign levels of confidence to categorisation of births as preterm, utilising assessment modalities which may be available across different settings. These are designed to enable systematic safety evaluation of vaccine clinical trials and post-implementation programmes of immunisations in pregnancy.

Patterns of health care resource utilization after macrolide treatment failure: results from a large, population-based cohort with acute sinusitis, acute bronchitis, and community-acquired pneumonia.

BACKGROUND: Macrolide antibiotics are used as first-line therapy for the treatment of respiratory tract infections. The recent emergence of macrolide-resistant pathogens is a major concern. OBJECTIVE: This study quantifies the frequency of macrolide treatment failure in respiratory infections and examines its impact on health care use. METHODS: Patients with respiratory infections treated with macrolides in outpatient clinics from January to December 2002 were identified from a health insurance claims database. Macrolide treatment failure was defined as the receipt of a second antibiotic, different from the first, within 4 weeks after the initial macrolide. The end points were numbers of hospitalizations and emergency department and office visits within 1 month after the initial macrolide. We examined diagnostic codes on claim forms for posttreatment hospitalizations and visits to identify those most likely to be related to treatment failure as opposed to other causes. Utilization data were analyzed by Poisson regression to control for confounding variables. RESULTS: The patients were divided into acute sinusitis (n = 111,135), acute bronchitis (n = 157,360), and community-acquired pneumonia (n = 36,212). Of these respective groups, 11,285 (10.2%), 15,498 (9.9%), and 4144 (11.4%) received a second antibiotic within 4 weeks. This subgroup with macrolide treatment failure was older, included more women, and had used more medical care before the index visit compared with patients with treatment success. After adjustment for age, sex, and previous health care use, patients experiencing treatment failure were more likely to be admitted to the hospital or to use emergency department or outpatient care after the index visit. This association was strongest for admissions and visits pertaining to the care of respiratory infections. CONCLUSIONS: By our definition, about 10% of patients with respiratory infections who were treated with macrolide antibiotics experienced treatment failure within 4 weeks. Macrolide treatment failure was associated with increased health care utilization.