Table 3

Timing of surveillance colonoscopy relative to recommended intervals according to guideline in effect (by period) and adenoma patient group, Kaplan-Meier analysis

Period of index colonoscopyRecommended interval (year)Too early (%)Appropriate* (%)Delayed or no surveillance (%)No surveillance† (%)
June 1998–2001
 1 adenoma (n=1676)2–324245335
 2 adenomas (n=397)14237332
 3+ adenomas (n=230)16306322
Overall (n=2303)19245733
In 2002
 1 adenoma (n=417)64794440
 2 adenomas (n=160)657113333
 3+ adenomas (n=117)339184333
Overall (n=694)48114137
Overall, all patients (n=2997)25215334
  • Due to rounding row percentages may not add up to 100%.

  • *Appropriate interval, before 2002: 1-year plus or minus 3 months, 2–3 years plus or minus 6 months; and in 2002: 3- or 6-years plus or minus 6 months.

  • †by the end of the study (1 December 2008) or within 90 months, whichever came first.