What the upper limit of normal for ALT should be, and why it is not
The reference interval for alanine aminotransferase in most laboratories is derived from a population that included people with undiagnosed fatty liver.
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Page 2 of 2 of this archive, newest first.
Which results are findings and which are consequences of the weight loss
The estimated glomerular filtration rate is calculated from creatinine, creatinine comes from muscle, and muscle mass is falling. The arithmetic is unforgiving.
What the outcome trials measured in the kidney
Estimated glomerular filtration rate is a calculation with muscle mass in the denominator of its assumptions. In this population that matters.
Which results are findings and which are consequences of the weight loss
Three different explanations for the same abnormal number, and how to tell them apart.
Why your laboratory interval differs from the one in the textbook
Two sources of noise sit under every number: how reproducible the assay is, and how much the analyte varies within the same person on the same day.
Thiamine and the vomiting patient
What the trials measured, which in the case of micronutrients is very little.
HbA1c and its lag: what a result three months old is telling you
A robust, cheap, standardised assay with a specific and well-catalogued set of failure modes, several of which are common in this population.
HbA1c and its lag: what a result three months old is telling you
What the SURPASS and STEP programmes reported, with the estimands and the baseline values stated.
Vitamin D, adiposity, and a volume-of-distribution problem
A monitoring schedule requires evidence about incidence. For this population, that evidence does not exist.
The out-of-range flag is a statistical convention with a printer attached
A flag is a probability statement about a population. It is not a statement about the person holding the printout.
A guide to the results that will resolve themselves
Three different explanations for the same abnormal number, and how to tell them apart.
Monitoring intervals, and the case against measuring too often
A panel that will not change a decision is a panel that generates work.
Which results are findings and which are consequences of the weight loss
Three different explanations for the same abnormal number, and how to tell them apart.
Which results are findings and which are consequences of the weight loss
Three different explanations for the same abnormal number, and how to tell them apart.
What the upper limit of normal for ALT should be, and why it is not
Estimated glomerular filtration rate is a calculation with muscle mass in the denominator of its assumptions. In this population that matters.
Vitamin D, adiposity, and a volume-of-distribution problem
Reduced intake is a plausible mechanism for deficiency. Reduced absorption is not, and the two are conflated in most of the advice.
The reference change value: the number that tells you whether a delta is real
Almost every misreading of a laboratory panel is a misunderstanding of what a reference interval is and how much a result has to move before the movement means anything.
Continuous monitoring changed the question and not the assay
HbA1c integrates roughly three months of glycaemia with the most recent weeks weighted most heavily. Almost every misreading of it is a misreading of that weighting.
The glycated haemoglobin assay, and the eight conditions that break it
The assay is not the problem. The interpretation of a lagging integral as a current measurement is the problem.