This example shows a study where subjects are randomized to standard treatment or an experimental treatment. The subjects who are randomized to standard treatment are given the option to receive experimental treatment after they end the standard treatment (e.g., due to disease progression on standard treatment). In the randomized treatment epoch, the disease assessment schedule changes over the course of the study. At the start of the extension treatment epoch, subjects are re-baselined, i.e., an extension baseline disease assessment is performed and the disease assessment schedule is restarted).
In this example, there are 3 distinct disease-assessment schedule patterns:
- The first disease-assessment schedule pattern starts at the reference start date (identified in the ADSL ANCH1DT variable) and repeats every 8 weeks for a total of 6 repeats ( i.e., week 8, week 16, week 24, week 32, week 40, week 48), with respective upper and lower limits of - 3 days and + 1 week.
- The second disease assessment schedule starts from week 48 and repeats every 12 weeks (week 60, week 72, etc.), with respective upper and lower limits of -1 week and + 1 week, for an indefinite length of time. The preceding schematic shows that, for the second pattern, assessments will occur until disease progression; this therefore leaves the pattern open-ended.
- The third disease assessment schedule starts at the extension reference start date (identified in the ADSL ANCH2DT variable) from week 96 and repeats every 24 weeks (week 120, week 144, etc.), with respective upper and lower limits of -1 week and + 1 week, for an indefinite length of time. The schematic shows that, for the third pattern, assessments will occur until disease progression; this therefore leaves the pattern open-ended.
For open-ended patterns, the total number of repeats can be identified when the data analysis is performed; the highest number of repeat assessments for any subject in that pattern must be recorded in the TDNUMRPT variable on the final pattern record.