Sekiguchi Y, Benjamin CL, Butler CR, et al. Relationships Between WUT (Body Weight, Urine Color, and Thirst Level) Criteria and Urine Indices of Hydration Status. Sports Health. September 2021. doi:10.1177/19417381211038494
The data for this article were interpreted incorrectly. The authors would like to alert readers to the following changes to this article:
Abstract
Results:
The sentence starting with “Meeting” and ending at “mOsm” has been changed to “Meeting at 3 WUT resulted in specificity of 0.956 and at 0 WUT resulted in sensitivity of 0.937 for urine osmolality >700 mOsm.” because of the changes of results.
Conclusion:
The sentence starting with “These” and ending at “points” has been changed to “These results suggest that when 3 WUT markers are met, urine specific gravity and urine osmolality indicated hypohydration and 0 WUT represents a high likelihood of euhydration; 1 and 2 WUT values are indeterminate of hydration status.” because the conclusion is slightly different now.
Body
Methods:
The sentence starting with “One-way” and ending at “hypohydration” has been changed to “One-way ANOVA with Tukey pairwise comparisons was used to assess the differences in USG, UOSM, %BML, UCOL, and thirst level between the different number of WUT markers that indicated hypohydration as each urine sample referred to an individual sample.” to give more explanation because statistical analyses was slightly different.
The sentences starting with “Sensitivity” and “true negative-1” have been deleted as no longer necessary.
Results:
Because results were different with new analyses, the sentences starting with “Satisfying” and ending at “44.9%” has been changed to “Satisfying 3 WUT criteria resulted in 13 samples diagnosed as very likely dehydrated, of which 8 met the USG >1.020 threshold. This resulted in a sensitivity of 0.088 and 0.079, and specificity of 0.964 and 0.956 for USG and UOSM, respectively. These specificity values indicated this test was good at detecting hypohydration when 3 factors are positive.”
The sentence “Satisfying 0 WUT criteria, sensitivities were 0.938 and 0.937 for USG and UOSM, respectively, which indicated this test was good at detecting euhydration.” was added after the sentence ending with “hypohydrated”.
The sentences starting with “Meeting” and ending at “contexts” were deleted because this information was no longer correct.
The sentence starting with “Positive” and ending at “mOsm” has been changed to “Positive predictive value increased as more the number of WUT (0, 1, 2, or 3) was greater (Table 2) for USG >1.020 and for UOSM >700 mOsm.” because data were changed after new analyses.
The sentence starting with “Negative” and ending at “condition)” has been changed to “Negative predictive values for both USG and UOSM were greater than positive predictive values supporting the accuracy of WUT decision tool in identifying euhydrated subjects (negative condition) when WUT criteria indicated 0 or 1.” because data needed to be updated.
Data in Table 2 were updated after new analyses.
Discussion:
After updating the results, the sentences starting with “The current” and ending at “participants” have been changed to “The current study has the following findings: (1) meeting at 3 WUT criteria for defining very likely dehydrated significantly indicates hypohydrated state defined by USG (>1.020) or UOSM (>700 mOsm), (2) meeting at 0 WUT criteria indicates euhydrated state, (3) calculation of positive and negative values interpretation of WUT criteria fulfillment as likely or very likely dehydrated and indicates potential impact in high prevalence (e.g., many dehydrated individuals) field settings, and (4) WUT criterion based on thirst contributes to gaps in accuracy in detecting hypohydration among subjects.”
Table 2.
Sensitivity, specificity, cutoff determination value (* indicates sensitivity > cutoff determination value, which indicates differentiating hypohydrated vs. euhydrated subjects), positive and negative predictive value, number of total diagnosed using respective WUT criteria, and distribution of subjects based on urine specific gravity (USG)>1.020 and urine osmolality >700 mOsmol. Gray shaded area indicates subjects defined as likely or very dehydrated (bold-faced text) or euhydrated for matching with number of WUT criteria (3, 2, 1, 0) met
| Urine specific gravity | ||||||||
|---|---|---|---|---|---|---|---|---|
| # of WUT markers | Sensitivity | Specificity | Cutoff determination value | Positive predictive value | Negative predictive value | # of total diagnosed using WUT criteria | Distribution of subjects based on USG>1.020 threshold | |
| Hypohydration | Euhydration | |||||||
| 3 | 0.088 | 0.964 | 0.833 | 61.5% | 38.5% | 13 | 8 | 5 |
| 2 | 0.659 | 0.572 | 0.299* | 49.1% | 50.9% | 106 | 52 | 54 |
| 1 | 0.340 | 0.428 | 0.763 | 28.7% | 71.3% | 87 | 25 | 62 |
| 0 | 0.938 | 0.123 | 0.773* | 26.1% | 73.9% | 23 | 6 | 17 |
| Total | 229 | 91 | 138 | |||||
| Urine osmolality (mOsmol) | ||||||||
| # of WUT markers | Sensitivity | Specificity | Cutoff determination value | Positive predictive value | Negative predictive value | # of total diagnosed using WUT criteria | Distribution of subjects based on urine osmolality >700 mOsmol threshold | |
| Hypohydration | Euhydration | |||||||
| 3 | 0.079 | 0.956 | 0.850 | 53.8% | 46.2% | 13 | 7 | 6 |
| 2 | 0.652 | 0.570 | 0.306* | 49.5% | 50.5% | 103 | 51 | 52 |
| 1 | 0.348 | 0.430 | 0.750 | 29.4% | 70.6% | 85 | 25 | 60 |
| 0 | 0.937 | 0.126 | 0.768* | 26.1% | 73.9% | 23 | 6 | 17 |
| Total | 224 | 89 | 135 | |||||
After updating the results, the sentences starting with “Sensitivities” and ending at “levels” have been changed to “Specificities were greater than 95% to demonstrate USG >1.020 and UOSM >700 mOsm (USG, 0.964; UOSM, 0.956) when 3 WUT criteria indicating hypohydration levels. Additionally, WUT criteria identified euhydration as explained by high sensitivities, 0.938 and 0.937 for USG and UOSM, respectively. However, both sensitivities and specificities were not high with 0 and 1 WUT criteria, which indicated they were not good to detect either hypohydration nor euhydration.”
The phrase “at least likely” has been deleted from the sentence starting from “In” and ending with “results”.
Because interpretations were different based on results changes, the sentences starting with “Positive” and ending at “incorrectly” have been changed to “Positive predictive values for detecting hypohydration (by USG and UOSM) increased as with 0 (26.1% and 26.1%) 1 (28.7% and 29.4%), 2 (49.1% and 49.5%), or 3 (61.5% and 53.8%). Negative predictive values increased as fewer markers were included; this indicates better probability of accuracy (70%> with 1 and 0) in detecting true euhydration. In other words, meeting criteria for classification as euhydrated with fewer markers indicated better true negative (detecting euhydration). Using USG and UOSM as the external classifying variable with which to validate WUT criteria diagnoses, decreased false negative rates as fewer markers were satisfied, which means there was less chance of detecting euhydration incorrectly.”
Conclusion:
Because of changes to the results, the sentences starting with “The” and ending at “hypohydration” have been changed to “The WUT criteria with 3 and 0 can be used to identify hypohydration and euhdyration, respectively. However, the WUT criteria with 2 and 1 might not be good at distinguishing hypohydration and euhydration. In particular, when the markers were BML and thirst, WUT 2 did not detect hypohydration. Because of its complex physiological nature, thirst has been identified as a variable that contributes to lack of precision in identifying level of hypohydration.”
The online version of this article has been updated.