![]() It approximates RR, especially for rare outcomes, is more universally appropropriate than RR, and has mathematical advantages over RR. Odds ratio is the ratio of odds for the exposed group vs the unexposed group. Thus the odds of throwing a three with one die is 1/5. Odds are the probability of an event happening / the probability of an event not happening. The population attributable risk (PAR) is the amount of absolute risk due to a given exposure, and is the attributable risk x the prevalence of exposure in the population. It assumes causality, in that the level of absolute risk in the exposed group is due to exposure. It is calculated as the arthmetic difference of incidence rates in exposed minus unexposed rates, or. While relative risk indicates the strength of an association, the attributable risk (risk difference) provides absolute value of size of the effect. It is measured by # of events / # of trials. Risk, or probability, is the likelihood an event will occur. Instead, the rates of a standard population are combined with the rates of the study population to yield the 'standardized morbidity ratio'. Indirect adjustment is used to compare populations whose specific rates are unknown. ( # existing cases in a time / total population ) x unit populationĪdjustment or standardization can remove the effects of confounders when comparing two or more populations.ĭirect adjustment uses the averages of specific rates of a study population, weighted according to the distribution of a standard population. Usually described per unit of population. Prevalence changes the positive and negative predictive value of screeing tests. Chronic diseases have a higher prevalence than incidence, while many infectious diseases have high incidence but low prevalence. Gaussian kernel density estimator is viable for radon data.Prevalence is the total number of people who have a condition at any one time point.The miner's relative risk models produce good estimates for population attributable risk for dwelling data.Population attributable risk is sensitive to recitative risk model and probability distribution choices.Many cases of lung cancer in Canada and its provinces are associated with residential radon.Empirical, log-normal, and Gaussian kernel density estimation with support [0,∞) can all be applied to radon data. Miners' models can be used for residential radon. PAR is sensitive to the choice of RR model. Conclusion: Many lung cancer cases could be prevented in Canada by reducing indoor radon. Gaussian kernel estimator produces PAR estimates similar to the commonly used log-normal distribution. PAR values for ES females are greater than those for ES males, except in Saskatchewan, Northwest Territories, Nunavut, and Yukon. There is little difference in results between miners' models and dwelling models. Results: PAR for the Canadian data is sensitive to the model choice, and it varies with a range of 10% for ES and 32% for NS, respectively. Finally, cancer death cases attributable to radon are reported for the constant relative risk model for the three distributions and the reduction in the cases when the action level 200 Bq/m 3 is applied. The second sample consists of 1800 people with 1. PAR was then calculated for Canada and its provinces using the empirical, log-normal, and Gaussian kernel estimates distributions. The first sample consists of 20 people with 10 having a common attribute. ![]() The original discrete radon data for Canada overall and for each of its provinces are estimated using log-normal and Gaussian kernel density estimator distributions. Smoking data (Ever Smoking ES and Never Smoking NS) collected in 2009 was also used in this study. The death rates used for this study were from the period 2006–2009. Methods: Using Canadian observed first floor radon data collected by Health Canada during the period October 2010 to March 2011, seven common PAR radon models used for North American miners and dwelling scenarios were applied. The aim of this study is to assess how sensitive PAR is to the relative risk model and radon probability distribution functions choices. Different relative risk (RR) models have been used in the literature to calculate PAR. The Population Attributable Risk (PAR) estimates the proportion of lung cancer cases associated with indoor radon exposure. Indoor radon has been identified as the second leading cause of lung cancer after tobacco smoking.
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