Optimization Output for Exp. 98 | QMRA wiki

Basic information

Experiment ID	98
Pathogen	Escherichia coli
Agent Strain	EIEC 1624
Contains Preferred Model	Yes
Reference	DuPont, H. L., Formal, S. B., Hornick, R. B., Snyder, M. J., Libonati, J. P., Sheahan, D. G., … Kalas, J. P. (1971). Pathogenesis of Escherichia coli diarrhea. The New England Journal of Medicine, 285, 1.
Exposure Route	oral (in milk)
Response	positive stool isolation

Detailed information

Host type

human

# of Doses

3.00

Dose Units

CFU

Μodel

beta-Poisson

a

1.55E-01

N50

2.11E+06

LD50/ID50

2.11E+06

Experiment Dataset

Description

**Escherichia coli** **(EIEC 1624) in the human model data**
Dose	Positive stool isolation	No positive stool isolation	Total
1E+04	0	5	5
1E+06	5	4	9
1E+08	3	2	5

**Goodness of fit and model selection**
Model	Deviance	Δ	Degrees of freedom	χ²_0.95,1 p-value	χ²_0.95,m-k p-value
Exponential	28.6	27.2	2	3.84 1.82e-07	5.99 6.18e-07
Beta Poisson	1.38	27.2	1	3.84 1.82e-07	3.84 0.24
Beta-Poisson fits better than exponential; cannot reject good fit for beta-Poisson.

**Optimized parameters for the beta-Poisson model, from 10000 bootstrap iterations**
Parameter	MLE estimate	Percentiles
Parameter	MLE estimate	0.5%	2.5%	5%	95%	97.5%	99.5%
α	1.55E-01	1.26E-03	1.26E-03	2.84E-02	1.84E+01	1.29E+02	1.90E+02
N₅₀	2.11E+06	1.73E+05	2.95E+05	2.95E+05	7.85E+08	9.22E+140	9.22E+140

Parameter scatter plot for beta Poisson model ellipses signify the 0.9, 0.95 and 0.99 confidence of the parameters.

beta Poisson model plot, with confidence bounds around optimized mode

References

DuPont, H. L., Formal, S. B., Hornick, R. B., Snyder, M. J., Libonati, J. P., Sheahan, D. G., … Kalas, J. P. (1971). Pathogenesis of Escherichia coli diarrhea. The New England Journal of Medicine, 285, 1.