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Probabilistic Bias Analysis

بنام او كه آگاه بر هر نهان است و دانا بر هر حقيقت. دانشگاه علوم پزشكي كرمان. Probabilistic Bias Analysis. علي اكبر حقدوست، اپيدميولوژيست. Applications.

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Probabilistic Bias Analysis

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  1. بنام او كه آگاه بر هر نهان است و دانا بر هر حقيقت دانشگاه علوم پزشكي كرمان Probabilistic Bias Analysis علي اكبر حقدوست، اپيدميولوژيست

  2. Applications With probabilistic bias analysis, the investigator specifies probability distributions for each of the bias parameters, and then uses Monte Carlo sampling techniques to generate a frequency distribution of corrected estimates of effect. علي اكبر حقدوست

  3. Relationship between smoking during pregnancy and breast cancer What would be the results if we assume that the sensitivity of our question was 78%? How much you are sure that the sensitivity is exactly 78%? What would be the results if I assume it ranges between 68% and 88% علي اكبر حقدوست

  4. Probability distribution • To conduct a probabilistic bias analysis, we need to specify a probability distribution for all or some of the bias parameters • Discrete probability distribution, which is also called a probability mass function • Continuous probability distribution, which is also called a probability density function علي اكبر حقدوست

  5. Uniform Distribution randommin,max=min+u·(max-min) علي اكبر حقدوست

  6. Trapezoidal Distribution علي اكبر حقدوست

  7. Triangular Distribution علي اكبر حقدوست

  8. Normal Distribution علي اكبر حقدوست

  9. Beta Distribution علي اكبر حقدوست

  10. Beta Distribution an approximate guide for choosing values for Alpha and Beta is to specify a range of likely values with minimum = a and maximum = c , and also a mode = b The mean of the beta distribution then approximately equals ( a + 4 b + c )/6 and the standard deviation equals ( c − a )/6. علي اكبر حقدوست

  11. Beta Distribution علي اكبر حقدوست

  12. Comparing different distributions علي اكبر حقدوست

  13. Sensitivity analysis علي اكبر حقدوست

  14. Sensitivity analysis with different distributions علي اكبر حقدوست

  15. Exposure Misclassification Implementation sensitivity (SE) of 78% specificity (SP) of 99% and for the misclassification to be non-differential علي اكبر حقدوست

  16. Exposure Misclassification Implementation uniform distribution for both sensitivity and specificity; we have to multiple two distributions علي اكبر حقدوست

  17. Unmeasured Confounding Implementation the prevalence of being Muslim vs. any other religion was 80% among circumcised men ( p1) and 5% among uncircumcised men ( p0 ). Muslim men had 0.63 times the risk of acquiring HIV as men who did not (RRCD). علي اكبر حقدوست

  18. علي اكبر حقدوست

  19. علي اكبر حقدوست

  20. Selection Bias Implementation علي اكبر حقدوست

  21. Correlated Distributions علي اكبر حقدوست

  22. Impossible Values for Bias Parameters علي اكبر حقدوست

  23. Combining Systematic and Random Error علي اكبر حقدوست

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