Background:
To encourage chlamydia screening, three states, Georgia (GA), Tennessee (TN), and Maryland (MD) have enacted laws requiring health plans to reimburse for the cost of chlamydia screening tests in women (and men for Maryland).

Objective:
To evaluate the effect of the laws on screening rates for the target population.

Method:
Monthly chlamydia screening rates in privately-insured women aged 12 to 29 years were extracted from January 1996 through December 2005 from an insurance claims database. We used eight Current Procedural Terminology (CPT) codes, including six (87110, 87270, 87320, 87490, 87491, and 87810) designated for chlamydia screening by NCQA's Health Plan Employer Data and Information Set (HEDIS) and two dual assays - direct (87800) and amplified (87801) probe techniques for multiple organisms. Screening rates from ten other southern states were used as the control in a panel data analysis approach. MD was dropped because of lack of enrollees and testing claims.

Result:
Screening rates for GA and TN have increased by over 10-fold over the last decade. However, although there is significant increase in screening rates in GA and TN after the enactment of the laws, similar increases were seen in the other southern states. There was no significant effect in GA and TN attributable to the screening laws compared to states without laws.

Conclusion:
In spite of the increase in screening rates after the laws came into effect within the two states, the increase cannot be attributed to the laws when compared with other southern states that do not have the laws.

Implications:
More studies need to be carried out using different sources of data on private insurance to better assess the effectiveness of the laws within the individual states and to test alternate hypotheses regarding chlamydia testing rate changes.