31. Using data from the Lothian Birth Cohort studies , Deary and colleagues have investigated the effects of ageing on cognition. 32. This was confirmed by another meta-analysis involving 945 286 patients in 8 retrospective cohort studies , most in the US. 33. Their results, however, can inform the design of slow and expensive longitudinal large-cohort studies that are definitive, for example. 34. Data from observational cohort studies have not shown a consistent association between flavan-3-ol intake and risk of cardiovascuar diseases. 35. A cohort study is a quasi-experiment used in medicine, nursing, correlations to determine the absolute risk of subject contraction. 36. Cohort studies are largely about the life histories of segments of populations, and the individual people who constitute these segments.37. In cohort studies , obtaining a gold standard test on every patient may not always be ethical, practical, or cost effective. 38. The value of a cohort study depends on the researchers'capacity to stay in touch with all members of the cohort. 39. Many scientific articles have been published on the health and nutrition properties of a vegetarian diet from these cohort studies . 40. A cohort study of miners employed at the mine reported that 85 deaths attributable to mesothelioma had occurred by 1985.
