The consistency of relative incidence rates of nonviral sexually transmissible infections from health insurance claims and surveillance data, 2005-10.

BACKGROUND

Given the growing popularity of administrative data for health research, information on the differences and similarities between administrative data and customary data sources (e.g. surveillance) will help to inform the use of administrative data in the field of sexually transmissible infections (STIs). The objective of this study was to compare the incidence rates of three nonviral STIs from a large health insurance administrative database (MarketScan) with surveillance data.

METHODS

We computed and compared STI rates for 2005-10 from MarketScan and national surveillance data for three major nonviral STIs (i.e. chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae) and syphilis (Treponema pallidum)). For administrative data, we assessed the sensitivity of the rates to enrollee inclusion criteria: continuous (≥320 member-days) versus all enrollees. Relative rates were computed for 5-year age groups and by gender.

RESULTS

The administrative database rates were significantly lower (P<0.01) than those in the national surveillance data, except for syphilis in females. Gonorrhoea and syphilis rates based on administrative data were significantly lower (P<0.01) for all enrollees versus continuous enrollees only. The relative STI rates by age group from the administrative data were similar to those in the surveillance data.

CONCLUSIONS

Although absolute STI rates in administrative data were lower than in the surveillance data, relative STI rates from administrative data were consistent with national surveillance data. For gonorrhoea and syphilis, the estimated rates from administrative data were sensitive to the enrollee inclusion criteria. Future studies should examine the potential for administrative data to complement surveillance data.