Difference between revisions of "Multistage model"

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The [[multistage model]] is a dose-response model that attempts to reflect the biological process of carcinogenesis.
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The '''multistage model''' is a dose-response model that attempts to reflect the biological process of carcinogenesis.
  
 
P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...))
 
P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...))
  
[[Category:Health effects]]
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[[Category:Needs editing]]
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A more simple 
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the formula for (excess) risk is:
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P(dose) = 1 - exp [-alfao +alfa1 *
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dose1 +...alfak * dose]
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(alfa=dose-response)
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At
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risk levels (<10-2) the following linear formula can be used for the upper bound (95%) risk
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Risk = exposure (mg/kg/day) * q1 (risk per mg/kg/day)
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q1=cancer slope factor, upper 95% confidence limit,
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calculated from 10% point of departure (POD)
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from experimental data
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See e.g. Casarett & Doull's Toxicology
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 , 6th ed. 2001, p. 95-97.
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[[Category:Health_effects]] [[Category:Needs_editing]]

Revision as of 07:29, 27 March 2008

The multistage model is a dose-response model that attempts to reflect the biological process of carcinogenesis.

P(Response|Dose)= background +(1-background)*(1-exp(-q1*Dose -q2*Dose^2 -q3*Dose^3...))



A more simple 


the formula for (excess) risk is:


P(dose) = 1 - exp [-alfao +alfa1 *


dose1 +...alfak * dose]

(alfa=dose-response)



At


risk levels (<10-2) the following linear formula can be used for the upper bound (95%) risk

Risk = exposure (mg/kg/day) * q1 (risk per mg/kg/day)

q1=cancer slope factor, upper 95% confidence limit,


calculated from 10% point of departure (POD)


from experimental data


See e.g. Casarett & Doull's Toxicology


 , 6th ed. 2001, p. 95-97.