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. 2015 Mar 6;59(6):764–774. doi: 10.1093/annhyg/mev011

Table 2.

Sequence of log linear models calculated for sensitizer scores adjusted for disease status.

Model no. Model description Parametersa Model df Deviance Comparison df Comparison G2 P valueb AICc
1 Exact + association + case/control + interactions cc + λ 1+ λ 2 + δ + β + cc*δ + cc*β 5491 1899.7 3139.7
2d Exact + association + case/control + association interaction cc + λ 1 + λ 2 + δ + β + cc*β 5492 1899.8 1 0.04 0.840 3137.8
3d Exact + association + case/control + exact interaction cc + λ 1+ λ 2 + δ + β + cc*δ 5492 1900.5 1 0.73 0.392 3138.5
4e Exact + case/control + exact interaction cc + λ 1+ λ 2 + δ + cc*δ 5493 1945.0 2 45.25 <0.001 3181.0
5e Association + case/control + association interaction cc + λ 1+ λ 2 + β + cc*β 5493 1907.5 2 7.78 0.020 3143.5
6f Exact + association + case/control cc + λ 1 + λ 2 + δ + β 5493 1900.5 2 0.74 0.691 3136.5
7g Exact + association λ 1 + λ 2 + δ + β 5494 1900.5 3 0.74 0.864 3134.5
8h Exact λ 1 + λ 2 + δ 5495 1944.9 4 45.17 <0.001 3177.0
9h Association λ 1 + λ 2 + β 5495 1908.2 4 8.47 0.076 3140.2

aAll models contain an intercept term λ 0 (not shown).

b P value based on χ2 distribution where χ2 = delta G2 (the difference in deviance between the reduced and full model) with degrees of freedom as the difference in df between models. All models compared to model no. 1.

cAkeike information criterion (AIC) = −2 × (log likelihood − number of parameters).

dModels 2 & 3 show the alternate removal of the cc × agreement (δ or β) interaction term; neither model shows a significant difference from the full model.

eModels 4 & 5 show the alternate removal of the agreement terms (δ or β) and their corresponding interaction terms. Both models show a significant difference from the full model indicating a need for both δ and β in the model to achieve proper fit.

fModel 6 shows the removal of all interaction terms, with no significant difference from the full model.

gModel 7 shows the removal of case/control status from model 6, again showing no difference from the full model.

hModels 8 and 9 show the models containing only one or the other agreement terms. Model 8 containing δ only shows a significant difference from the full model. Model 9 containing β only shows a marginally significant difference from the full model. Among the reduced models AIC is at a minimum for Model 7 which contains δ and β.