Table 3

Multivariable Box-Jenkins transfer function model used to estimate times series having impact on CDAD incidencea

Time seriesCDAD incidence
January 2005-December 2008August 2005-December 2008
OrderbParameter value (SE)P valueOrderParameter value (SE)P value
CDAD incidenceAR1c0.97774 (0.02868)<0.0001AR10.90329 (0.06822)<0.0001
Influenza virus10.03975 (0.01964)0.04310.03587 (0.01808)0.0472
RSV10.05093 (0.0434)0.004010.03885 (0.01328)0.0034
Fluoroquinolones20.00038 (0.0136)0.013620.00029 (0.00014)0.0433
Macrolides10.00012 (0.00006)0.054210.00011 (0.00006)0.0484
  • a Reported parameters for influenza virus, RSV, and antibiotics describe the transfer functions.

  • b Delay in months before the effect is observed.

  • c AR1, autoregressive term of first order representing the past values of the CDAD incidence.