This paper distills and extends recent research on the economics of human development and social mobility. It summarizes the evidence from diverse literatures on the importance of early life conditions in shaping multiple life skills and the evidence on critical and sensitive investment periods for shaping different skills. It presents economic models that rationalize the evidence and unify the...

We look at fitting regression models using data from stratified cluster samples when the strata may depend in some way on the observed responses within clusters. One important subclass of examples is that of family studies in genetic epidemiology, where the probability of selecting a family into the study depends on the incidence of disease within the family. We develop the survey-weighted esti...

This paper presents an information-boundaries perspective on the family and the Internet with the aim of helping to set the context for child development in the new media environment. Drawing from family studies, sociology, and communication, it lays out a model for viewing the family in relation to the Web. The paper draws research ideas out of the framework that center on four areas: family c...

BACKGROUND Close contacts of patients with tuberculosis (TB) have a substantial risk of developing the disease, particularly during the first year after exposure. Household contact investigation has recently been recommended as a strategy to enhance case detection in high-burden countries. However the barriers to its implementation in these settings remain poorly understood. METHODS A nested ...

Previous twin and family studies indicate that the familial aggregation of breast density is due (in part) to genetic factors. Whether these genetic influences are shared with other breast cancer risk factors, however, is not known. Using standard film-screen mammography, we screened 550 women, including 611 pairs of sisters, from the Old Order Amish population of Lancaster County, Pennsylvania...

I N 1962, STORMONT surveyed 66 known antigenic factors of the red cells of cattle. These factors were designated A, B, C, . . . Z, A’ . . . etc., and a few new ones were designated by number. Peculiar constellations of factors occurred nonrandomly in population data ( STORMONT, OWEN and IRWIN 1951 ) and family studies confirmed the genetic transmission of particular groups of factors as entitie...

RATIONALE Some clusters of patients who have Mycobacterium tuberculosis isolates with identical DNA fingerprint patterns grow faster than others. It is unclear what predictors determine cluster growth. OBJECTIVES To assess whether the development of a tuberculosis (TB) outbreak can be predicted by the characteristics of its first two patients. METHODS Demographic and clinical data of all cu...

We read with great interest the article by DIEL et al. [1] in a recent issue of the European Respiratory Journal. We believe that the authors have been successful in modelling and analysing the cost of alternatives for tuberculosis (TB) contact investigation. Nevertheless, we have some hesitation regarding a simplifying assumption that the authors have made in the follow-up of subjects after a ...

preferable. In such a study design, an affected individual and other members of the family (parents if available, otherwise siblings) are ascertained and the probability of transmission of the different alleles at the locus under study from parents to the affected individual calculated. Because transmission is being studied, there is no problem with population substructure between cases and con...

OBJECTIVE Standard methods for linkage analysis ignore the phenotype of the parents when they are not genotyped. However, this information can be useful for gene mapping. In this paper we propose methods for age at onset genetic linkage analysis in sibling pairs, taking into account parental age at onset. METHODS Two new score statistics are derived, one from an additive gamma frailty model a...