Repeated cross-sectional surveys may underestimate past smoking behavior of older age cohorts true or false
Posted Aug 26 2019
Answered on Aug 27 2019
Cross-sectional studies are studies that analyze data from a population or subset of the population over a specific period of time. They do not indicate the cause of the disease or the results of the intervention. Cumulative initiation can be underestimated as older people who start smoking earlier may die earlier. Similarly, older people tend to indicate an older smoking initiation age than their actual initiation age. Older people may also have memory problems, which can make it difficult for them to remember the actual time of smoking initiation or behaviour. Therefore, the smoking behavior of the elderly may change depending on the population studied. They can report different numbers of cigarettes smoked than the actual numbers. Sample sizes vary in repeated cross-sectional studies. Stigma also lead to under-reporting of smoking behavior. Older women may report erroneous smoking initiation time/behavior or may not report it at all. Large variations occur in the age of the persons tested. Statistical errors can therefore lead to misestimation of smoking behaviour. Furthermore, smoking behavior is observed in different individuals and can lead to statistical differences in the estimates being undermined. Therefore, the statement is true.
Greenhouse producers often supplement the atmospheres in their facilities with extra CO2. This addition increases plant growth, leading to more rapid plant production for sale. Describe (1) how this supplemental CO2 benefits growth and the physiological and biochemical level and (2) what drawbacks the plant might face upon transplanting to a homeownerâs garden.