We assessed whether excluding individuals without complete congener profiles biased various total TCDD TEQ estimates calculated using both the WHO₁₉₉₈ and WHO₂₀₀₆ TEFs.

PCDD/F and PCB serum concentration data collected as part of the 2001–2002 National Health and Nutrition Examination Survey were obtained from the National Center for Health Statistics, and total TCDD TEQ concentrations were calculated by summing the product of each congener’s concentration and its associated WHO₁₉₉₈ or WHO₂₀₀₆ TEF. Individuals 20 years and older who were not missing all 17 PCDD/F congeners or all 26 dioxin-like congeners were included in these analyses. Comparison of estimates reported previously with estimates calculated for these analyses were made by assessing both absolute differences and percent differences of each statistic by TEQ subgroup.

The average percent difference in the mean, median, and 95^th percentile TEQ_PCDD/F was 2.09, 1.15, and 0.89%, respectively, using the WHO₁₉₉₈ TEFs and 1.86, 1.39, and 0.56%, respectively, using the WHO₂₀₀₆ TEFs, while the average percent difference in the mean, median, and 95^th percentile TEQ_17–9 was 1.35, 0.79, and -0.85% (WHO₁₉₉₈ TEFs), respectively, and 1.60, 1.23, and -1.50% (WHO₂₀₀₆ TEFs), respectively. Examination of estimates for particular subgroups demonstrated that the 95^th percentile TEQ_PCDD/F and TEQ_17–9 reported previously for males 20–29 years of age were moderately underestimated and that the 95^th percentile TEQ_PCDD/F and TEQ_17–9 reported previously for males 30–44 years of age were slightly overestimated.

While the 95^th percentile for certain subgroups were impacted more than others, summary statistics reported previously were not greatly influenced due to excluding individuals without complete congener profiles.