Table 2.

A description of data manipulation techniques applied to allen’s relations to minimize discrepancies in the OAT data and support the construction of monotherapy episodes

Allen’s Relations	Manipulation Techniques	Descriptions
	Concatenation	Linked consecutive dispensations with no gap to create a continuous single-OAT treatment.
	Temporal Margin ()	Relaxed Allen’s overlaps relation using the concept of to differentiate between short and long overlaps under the following conditions: If the overlap duration was ≤ days, we shifted the start date of the subsequent dispensation forward and reclassified the temporal relation from overlaps to meets. If the overlap duration was > days, no adjustments were made.
	Permissible Gap	Integrated Allen’s relation with OAT-specific permissible gaps to allow short interruptions within a continuous treatment. If gaps in the before relation exceeded the permissible gap, we classified the OAT as discontinued.
	Aggregation	The two dispensations were merged at the common start date value, and the daily dose was added for the nested period.
	Aggregation	The two dispensations were merged at the common end date value, and the daily dose was added for the nested period.
	Aggregation	The two dispensations were merged, using the start and end dates of the dispensation with the larger days supply, and the daily dose was added for the nested period.
	Aggregation	The two dispensations were merged, using the start and end dates from one of the two dispensations. The daily dose was added for the nested period.

Note: Appendix 4, Example 5 provides an example of applying these techniques to PharmaNet dispensations for monotherapy episode construction