Why your laboratory interval differs from the one in the textbook
A twelve-analyte panel in a perfectly healthy person has roughly even odds of producing at least one flagged result.
Kidney
Renal outcomes, the FLOW trial, and eGFR trajectory during rapid weight loss.
EGFR, cystatin C, and the check on the check
What the renal and hepatic outcome programmes actually measured, and over what duration.
What a low result means when intake has halved
Reduced intake is a plausible mechanism for deficiency. Reduced absorption is not, and the two are conflated in most of the advice.
HbA1c and its lag: what a result three months old is telling you
The assay is not the problem. The interpretation of a lagging integral as a current measurement is the problem.
Which results are findings and which are consequences of the weight loss
A substantial proportion of the abnormal results generated during rapid weight loss are consequences of the weight loss rather than findings about the person.
What the upper limit of normal for ALT should be, and why it is not
What the renal and hepatic outcome programmes actually measured, and over what duration.
What a low result means when intake has halved
What the trials measured, which in the case of micronutrients is very little.
Reading HbA1c in the presence of anaemia
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.
Measuring more frequently generates more flags and not more information
The argument for a baseline panel is that it makes every subsequent result interpretable. The argument against frequent monitoring is that noise accumulates faster than…
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.
HbA1c and its lag: what a result three months old is telling you
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.
What the trials monitored, and what that implies about routine practice
The argument for a baseline panel is that it makes every subsequent result interpretable. The argument against frequent monitoring is that noise accumulates faster than…
What has to change before a change has happened
A flag is a probability statement about a population. It is not a statement about the person holding the printout.
EGFR, cystatin C, and the check on the check
The reference interval for alanine aminotransferase in most laboratories is derived from a population that included people with undiagnosed fatty liver.
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.
The out-of-range flag is a statistical convention with a printer attached
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.
A reference interval is not a target, and a result outside one is not a diagnosis
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.
Rapid weight loss moves eight analytes for reasons that have nothing to do with the drug
Three different explanations for the same abnormal number, and how to tell them apart.
Which results should be repeated before they are investigated
Timing is the whole of the post-cessation panel: draw it too early and it measures the treatment period.
Thiamine and the vomiting patient
Reduced intake is a plausible mechanism for deficiency. Reduced absorption is not, and the two are conflated in most of the advice.