A Modification of the Urine Osmolal Gap: An Improved Method for Estimating Urine Ammonium
Bibliographic record
Abstract
A modification of the urine osmolal gap was evaluated as an estimate of urine [NH4+]. We proposed that: Urine [NH4+] = Urine osmolality - [2(Na+ + K+) + urea + glucose]/2 Spot urine samples were collected from normal volunteers and from individuals with ketonuria; the modified urine osmolal gap as well as two other previously described estimates of urine [NH4+] were compared with measured urine [NH4+]. There was a significant positive linear correlation between the urine [NH4+] and the modified urine osmolal gap in normal volunteers (r = 0.81; p less than 0.01) and in individuals with ketonuria (r = 0.93; p less than 0.001). The originally described urine osmolal gap greatly overestimated the urine [NH4+] but also showed a significant correlation. The urine anion gap was not a valid estimate of urine [NH4+] within the range of values measured in our subjects. The modified urine osmolal gap is an improvement over previously described estimates of urine [NH4+] and can be used as a single calculation in place of the other two.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.006 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".