Erratum to: Ethnic differences in composite indices of femoral neck strength

Abstract

The scale factors provided by Hologic, Inc. to compute femoral neck axis length (FNAL) from the midline endpoint coordinates were off by a factor of 2; thus absolute values reported in Tables 1–4 of the paper for FNAL, bending strength index (BSI), and impact strength index (ISI) were scaled incorrectly. Corrected absolute values for FNAL and ISI are 0.5 times the reported FNAL and ISI values, and corrected absolute values for BSI are 2 times the reported BSI values. Thus, the FNAL rows in Tables 1 and 3 should be as shown below. The BSI and ISI cells in Tables 2 and 4 also need to be scaled by 2 and 0.5 respectively. For example, BSI in Caucasians (reference) in Table 2 (model 3) is 0.98; in US-born Chinese (reference) in Table 4 (model 3) is 1.14; and in US-born Japanese (reference) in Table 4 (model 3) is 1.24. Similarly, for example, ISI in Caucasians (reference) in Table 2 (model 3) is 0.18; in US-born Chinese (reference) in Table 4 (model 3) is 0.20; and in US-born Japanese (reference) in Table 4 (model 3) is 0.23. Note that effect sizes (and confidence intervals) for BSI and ISI in tables 2 and 4 are also similarly scaled.