Table 4.

Affinity matrix of Health Information Technology (HIT) interventions to control for doctor shopping.

Interventions	References	Occurrences (n = 42)	Frequency
PDMP	[13,26,28,31,38,39,41,43,49,50,51,54,55,56,60]	15	36%
National health system DB	[17,36,37,42,44,53,61]	7	17%
Computer model	[29,30,32,46,59]	5	12%
Combination	[11,16,27,34,54]	5	12%
Other	[15,33,35,52,57]	5	12%
Health insurance claims	[45,47,48]	3	7%
Health information exchange	[14,58]	2	5%