Mass Spectrometry Analysis of Urinary Methylmalonic Acid to Screen for Metabolic Vitamin B <sub>12</sub> Deficiency in Older Adults
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Aim: Vitamin B12 deficiency is characterized metabolically by increased serum and urine methylmalonic acid (MMA). Urinary MMA/creatinine ratio is suggested for screening for metabolic vitamin B12 deficiency in older populations. Results: A UPLC–MS/MS method for the analysis of urinary MMA and creatinine was developed/validated. A good separation of MMA from succinic acid, its structural isomer, was achieved. Intra- and interday accuracy biases and precision coefficients were all ≤6.3% for MMA and creatinine. Urine and serum samples of 34 individuals of the NuAge Biobank were analyzed for technical comparisons showing that urinary MMA/creatinine ratios by UPLC–MS/MS strongly correlated with GC–MS values, and with serum MMA values. Conclusion: The UPLC–MS/MS method developed is rapid/reliable for the analysis of urinary MMA/creatinine ratios.Graphical abstract
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Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.004 | 0.013 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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 it