One-year cumulative risk of infection among the patients with cetuximab and those without (n = 1083)<sup>a</sup>.

a<p>Stratum 1 had the strongest propensity for not receiving cetuximab therapy; stratum 5, for receiving cetuximab therapy.</p>b<p>Cochran-Mantel-Haenszel statistics; adjusted odds ratio = 2.27, 95% confidence interval = 1.46–3.54.</p>