Table 1.

Pearson correlation coefficients of ad clicks and influenza like illness reports from sentinel physicians (ILI-SPR) as measures for predicting influenza incidence data from the current or following week (all P < .001). (* see Figure 2, ** see Figure 3)

	Clicks	ILI-SPR
Same week
ILI-SPR	.73	—
Lab tests	.85	.83
Cases	.88	.80
Following week
ILI-SPR	.81	.71
Lab tests	.90	.82
Cases	.91 *	.75 **