International journal of epidemiology
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Multicenter Study
Maternal and biochemical predictors of spontaneous preterm birth among nulliparous women: a systematic analysis in relation to the degree of prematurity.
Nulliparous women are at increased risk of spontaneous preterm birth. Other maternal and biochemical risk factors have also been described. However, it is unclear whether these associations are strong enough to offer clinically useful prediction. It is also unclear whether the predictive power of these factors varies in relation to the degree of prematurity. ⋯ Time to event analytic methods can identify factors that are differentially associated with spontaneous preterm birth according to the degree of prematurity. However, models based on maternal and biochemical data perform poorly as a screening test for any degree of spontaneous preterm birth.
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The health benefits of physical activity are well established, but the overall amount of physical activity associated with cardiovascular and other health outcomes, and whether the relationships are similar in men and women and at different ages is still debated. This may be partly related to different methods for assessing physical activity. Most studies have focused on leisure time physical activity. ⋯ When both work and leisure time physical activity patterns are taken into account, using a simple, pragmatic, validated questionnaire feasible for use in clinical and public health practice, even very moderate levels of usual physical activity are associated with significantly reduced risk of mortality and cardiovascular disease in men and women in the general population and potential population attributable impact of 14% for inactive compared with active levels. These findings may encourage efforts to increase physical activity levels not only in leisure time but also in usual daily working life.
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Vital registration of causes of death in China is incomplete with poor coverage of medical certification. Information on the leading causes of mortality will continue to rely on verbal autopsy (VA) methods. A new international VA form is being considered for data collection in China, but it first needs to be validated to determine its operating characteristics. ⋯ VA is an imprecise tool for detecting leading causes of death among adults. However, much of the misclassification generally occurs within broad cause groups (e.g. CVD, respiratory diseases, and liver diseases). Moreover, compensating patterns of misclassification would appear to suggest that, in urban China at least, the method yields population-level cause-specific estimates that are reasonably reliable. These results suggest the possible utility of these methods in rural China, to back up the low coverage of medical certification of cause of death owing to poor access to health facilities there.
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Syndromes for which no physical or pathological changes can be found tend to be researched and managed in isolation although hypotheses suggest that they may be one entity. The objectives of our study were to investigate the co-occurrence, in the general population, of syndromes that are frequently unexplained and to evaluate whether they have common associated factors. ⋯ This study has shown that chronic syndromes that are frequently unexplained co-occur in the general population and share common associated factors. Primary care practitioners need to be aware of these characteristics so that management is appropriate at the outset.