Table 2.

Probability of Being Disease Free at 3 Years after Resection Based on a Normal Fasting Serum Gastrin Level and a Negative Secretin Test at Different Post-operative Times^*

Time after Surgery	Probability of Being Disease Free at 3 Years (95% CI)
1 Week†	75% (57% to 85%)
6 Month	88% (70% to 96%)
12 Month	95% (78% to 99%)
24 Month	100% (82% to 100%)

^*Twenty-seven patients were followed for at least 3 years: During this time, 8 patients developed recurrence. The probability of remaining disease free was estimated for 42 patients using the Kaplan-Meier method (see Figure 2), and 95% CIs were derived using Rothman’s method (see reference 41).

^†Calculated after excluding three patients who were achlorhydric.