Table 5.

Comparison of syndrome counts and model-based estimates of emergency department visits over the validation time period (January 1, 2007 to December 31, 2008) (error and correlation compared to NACRS ICD-coded heat-related emergency department visits).

	Training data		Validation data
	Correlation	MSE	Correlation	MSE
Syndrome counts time series	0.57	0.66	0.59	1.06
Poisson regression model	0.76	0.38	0.63	0.37
FOS model (weather predictors)	0.79	0.32	0.66	0.34
FOS model (weather and string count predictors)	0.82	0.30	0.73	0.29