Table 3.

A summary of survey frequency modeling^a to evaluate the incidence rate of reported arthritis in the dental amalgam filling surfaces group as compared to the other dental filling surfaces group in the NHANES database.

Exposure group examined	Total weighted persons reported to be diagnosed with arthritisb	Total weighted person-years	Outcome measurements
Dental amalgam filling surfaces group	2 501 064	3 917 945 204
Other dental filling surfaces group	124 556	1 175 073 798
Rate ratio (95% CI)			6.0 (2-21)
P value			<.001
Attributable rate difference per 10,000 (95% CI)			5.3 (2-9)

Bold-Italicized results are statistically significant.

Abbreviation: CI, confidence interval.

^aThe survey logistic model employed used stratum, cluster, and weight variables. The incidence rate of reported arthritis in the year of the NHANES survey was evaluated among those weighted-persons with ⩾1 amalgam filling surfaces (dental amalgam filling surfaces group) in comparison to those weighted-persons with ⩾1 other dental filling surfaces and 0 dental amalgam filling surfaces (other dental filling surfaces group).

^bThe incidence rate of reported arthritis was derived from NHANES survey data among those persons with reported arthritis in the year of the NHANES survey collection. Those persons with reported arthritis at any time prior to the year of the NHANES survey collection were eliminated from the analyses.