• Shuffle
Toggle On
Toggle Off
• Alphabetize
Toggle On
Toggle Off
• Front First
Toggle On
Toggle Off
• Both Sides
Toggle On
Toggle Off
Toggle On
Toggle Off
Front

### How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

Play button

Play button

Progress

1/17

Click to flip

### 17 Cards in this Set

• Front
• Back
 Number needed to treet 1/(Po-P1) = -1/RD Utility of Risk Risk Difference RD can have more clinical/public health meaning since is characterizes absolute risk RR vs. RD -RR is less dependent upon the underlying population. -RD provides incidence information. -No methods to do multivariate RD. 2 reasons to use OR 1) Logistic regression for fixed (defined) cohort studies. 2) Case-control estimates OR can estimate RR if D is infrequent in both E+ and E- min(Po,P1)<0.1 (10%) Major problems with risk, incidence, and odds information They do not measure the health "impact" of a particular exposure. Attributal fraction Proportion of the disease occurence that would be eliminated if exposure to the risk factor were prevented Attributable fraction: Synonyms -Etiologic fraction -attributable proportion -attributable risk -population attributable risk (percent) Who is the Attrubutable fraction calculated for? 1) E+ group 2) Entire population Attributable fraction for the exposed (discription) Proportion of cases in the E+ group attributable to E. Eg. Among NSAID users, what proportion of peptic ulcers are caused by NSAIDS? Attributable fraction for the exposed (Eqn) (P1-Po)/P1 (risk data) (I1-Io)/I1 (rate data) (RR-1)/RR (risk data) (IRR-1)/IRR (rate data) (OR-1)/OR (rare disease assumption) Attributable fraction for Population (disc) Proportion of cases in the population attributable to E. Eg. For a given patient population, what proportion of peptic ulcers are caused by NSAIDS? (need strength of the association between E and D and prevalence of E+) Attributable fraction for Population (eqns) (P-Po)/P (risk) (I-Io)/I (rate) ¶(RR-1)/[1+¶(RR-1)] (risk) ¶(IRR-1)/[1+¶(IRR-1)] (rate) ¶c(OR-1)/OR (Odds) Attributable Fraction for population (¶ and ¶c) ¶ = N1/N (proportion exposed in cohort for risk data) ¶ = T1/T (Proportion exposed for person-time for rates) ¶c = a/(a+b) (exposure prevalence in D+ for rare D) Attributable fraction for exposed (protective exposures) (disc) Also called prevented fraction or effictiveness. Often used in vaccine studies Attributable fraction for exposed (protective exposures)(eqn) 1)(Po-P1)/P1 1)1-RR Marginal cost-effecitiveness (Difference in cost)/(Events prevented) See 8-12