Table 4 The observed counts in 11 classes of the outcome variable and the expected frequencies predicted by the three fitted zero-inflated negative binomial regression (ZINB) models, including their values of the Akaike Information Criterion (AIC)

Days on sick leave	Observed	Model 1 (AIC 7029.4)	Model 2 (AIC 6976.3)	Model 3 (AIC 6961.4)
0	583	586	583	583
12	133	159	157	158
34	140	99	102	101
56	85	72	75	75
79	78	80	83	83
1013	76	74	77	77
1420	81	82	84	85
2127	43	50	50	50
2841	43	55	53	53
4283	46	53	47	47
84230	24	22	21	21