Abstract

Regarding our recent publication, “Association of lifetime exposure to fluoride and cognitive functions in Chinese children: A pilot study” [Neurotoxicology and Teratology 47 (2015) 96–101], the authors wish to correct the following errors in the reported results.

The last statement reported in 3. Results should be “Marginal significant mean differences in forward and total digit span scores were found between children with very mild/mild fluorosis and children with moderate/severe fluorosis.”

In addition, the footnote c in Table 5 should be “c?Significant mean difference between the 2 categories: very mild/mild and moderate/severe at 0.05 < p < 0.10.”

Table 5. Adjusted meansa (95% confidence intervals) of the neuropsychological tests by Dean Index among the 51 children.

Tests Normal/questionable
N = 8
Fluorosisb Very mild/mild
N = 9
Moderate/severe
N = 26
WRAML
 Finger windows 9.29 (6.65, 11.9) 10.2 (7.53, 12.9) 9.76 (7.44, 12.1)
 Visual learning total (Trials 1–4) 10.5 (5.55, 15.4) 11.5 (6.49, 16.6) 11.2 (6.86, 15.5)
 Visual learning delay 3.40 (1.15, 5.65) 3.90 (1.60, 6.20) 4.0 (2.02, 6.0)
 Visual learning difference (Trials 1–4 delay) ? 0.23 (? 1.80, 1.35) ? 1.64 (? 3.25, ? 0.03)c? ? 0.13 (? 1.51, 1.25)c?
 Design memory 16.5 (10.9, 22.0) 19.5 (13.9, 25.2) 20.2 (15.4, 25.1)
WISC-R
 Squareroot block design 2.22 (1.17, 3.27) 2.81 (1.74, 3.88) 2.54 (1.62, 3.46)
 Digit span
 Forward 9.38 (7.75, 11.0) 8.76 (7.09, 10.4)c? 7.24 (5.81, 8.67)c?
 Backward 3.20 (1.88, 4.51)d?? 1.86 (0.51, 3.20) 1.07 (? 0.08, 2.22)d??
 Total 12.6 (10.1, 15.0)d?? 10.6 (8.11, 13.1)c? 8.31 (6.15,10.5)c??d??
WRAMA drawing 12.1 (9.98, 14.2) 14.1 (11.9, 16.2) 13.3 (11.5, 15.1)
Finger tapping
 Preferred hand 29.5 (25.3, 33.6) 29.5 (25.3, 33.8) 28.7 (25.0, 32.3)
 Non-preferred hand 24.7 (21.3, 28.0) 29.8 (26.4, 33.2) 28.8 (25.8, 31.7)
Grooved pegboard
 log10 dominant hand 1.97 (1.90, 2.07) 1.98 (1.89, 2.06) 2.02 (1.95, 2.10)
 log10 non-dominant hand 2.06 (2.0, 2.14) 2.04 (1.97, 2.12) 2.06 (1.99, 2.12)

 

a Adjusted for child’s sex, age, parity, illness before 3 years old, household income last year, and caretaker’s age and education.

b As indicated by the Dean Index.

c. Significant mean difference between the 2 categories: Very mild/mild and moderate/severe at 0.05 < p < 0.10.

d.. Significant mean difference between the 2 categories: Normal/questionable and moderate/severe at p < 0.05.