Table 3. Mean number of prescriptions of the studied drug for controls and participating physicians during the mentioned time frame, weighted by the number of matching groups in the NIPMS.

Time frame	Mean duration (days)	Number of packages		DDD
		Control	NIPMS	Control	NIPMS
t0	365	102.4	103.4	7,705	7,753
t1	500	109.5	120.2	8,064	8,700
t2	365	102.1	110.3	7,736	8,314

Note that t1 is not the same duration as t0 and t2; number of prescriptions may be compared between groups during the same time frame, but not between time frames. Control = matched physicians, n = 4,642; NIPMS = physicians participating in an NIPMS, n = 2,354.

DDD, defined daily dose; NIPMS, non-interventional post-marketing study.