Every letter we have printed
Page 62 of 77 of this archive, newest first.
On “The fourteen-day problem, and what it does to a commercial testing model” — Analytics, 11 Jul 2024
On multiple-dose closures: the puncture budget you refer to is generally in single figures for a standard lyophilisation stopper, and the qualification uses a new needle each time. Anybody reusing a needle through the same entry point is outside the data entirely.
— B. Wojciechowski, Kraków
On “The limits of mechanism: why receptor data will not tell you who responds” — Explainers, 9 Jul 2024
I found the section on the area postrema genuinely clarifying. I had assumed nausea was a stomach problem and had been treating it as one, unsuccessfully, for four months.
— A. Mbeki, Lusaka
On “The limits of mechanism: why receptor data will not tell you who responds” — Explainers, 9 Jul 2024
You describe biased agonism as "legitimate and probably important" and then decline to say which molecules are biased in which direction. That is a strange place to stop.
— D. Mazzarella, Catania
It is, and it is deliberate. The published bias factors for these ligands are measured in different systems and are not comparable to one another. We would rather stop than publish a ranking that the underlying assays cannot support.
On “The limits of mechanism: why receptor data will not tell you who responds” — Explainers, 9 Jul 2024
A small thing: you write "class B GPCR" and then "secretin-like receptor" as though these were different classifications. They are the same family under two naming conventions, and the piece would be clearer if it said so.
— C. Rautenbach, Pretoria
Fair, and now stated in the text.
On “The limits of mechanism: why receptor data will not tell you who responds” — Explainers, 9 Jul 2024
I have been on treatment for fourteen months and stopped losing weight at month eleven. Your piece says this is energy balance rather than receptor desensitisation. I would find that easier to accept if anybody had explained it to me at the start rather than after I had spent two months assuming the drug had stopped working.
— R. Whitlam, Adelaide, SA
That is a fair criticism of the field rather than of this article, and we take the point about timing. The plateau is predictable and predicted; it is very rarely mentioned before it happens.
On “The mechanism behind the mechanism” — Pharmacology, 9 Jul 2024
As an anaesthetist I read the perioperative section with interest and one objection. You frame disclosure as the patient obligation. In my experience the failure is more often ours: the pre-assessment questionnaire in my own institution did not include these drugs until eighteen months after the first guidance appeared.
— T. Elorriaga, San Sebastián
A fair correction and we have amended the text. If the question is not on the form, the absence of an answer is not a patient failure. We would be interested to hear from readers in other institutions about whether their pre-assessment documentation has caught up.
On “The mechanism behind the mechanism” — Pharmacology, 9 Jul 2024
The gallbladder section says some of the excess is attributable to weight loss rather than the drug. If the drug causes the weight loss, is that not a distinction without a difference for the person who ends up in theatre?
— N. Halvorsen, Trondheim
For the individual, largely yes. For the question of whether one molecule is safer than another, or whether the risk would fall on slower loss, the distinction is the whole question. We should have made clear that it is a mechanistic distinction rather than a consoling one.
On “The mechanism behind the mechanism” — Pharmacology, 9 Jul 2024
You note that symptom burden does not predict weight outcome. This is the single most useful sentence I have read about this treatment. I spent four months believing that feeling well meant it was not working and considered increasing my dose on that basis alone.
— H. Baptiste, Fort-de-France
The folk model that suffering indexes efficacy is widespread and the published analyses do not support it. It is also actively harmful when it drives escalation, which is why we gave it a line in the closing section rather than burying it in the tables.
On “The mechanism behind the mechanism” — Pharmacology, 9 Jul 2024
Your incidence tables are from the licensed products. I use compounded material at a concentration that does not match any pen. Are the figures transferable at all?
— R. Hollenbeck, Spokane, WA
The mechanism transfers; the incidence figures transfer only to the extent that your actual exposure matches the trial exposure, which is unknown unless the content has been measured. That is not evasion. It is the reason we argue for peptide content as a standard reported field rather than purity alone.
On “The mechanism behind the mechanism” — Pharmacology, 9 Jul 2024
A small point of precision. You use "gastroparesis" in the tag list and then spend a paragraph saying it is not a synonym for drug-induced emptying delay. That is a slightly awkward position to hold.
— J. Vasilenko, Chisinau
It is, and it is a compromise with how readers search. The tag exists because that is the word people use; the glossary exists because it is the wrong one. We would rather be findable and then precise than precise and unread.
On “Why people actually stop, in the order they actually stop” — The Ledger, 8 Jul 2024
I stopped eight months ago after reaching a weight I was happy with, and I have regained four of the twenty-two kilograms I lost. Every article I read told me to expect two-thirds back. I am not complaining, but I would like to know whether I am unusual or whether the two-thirds figure was always a mean concealing an enormous range.
— H. Okwuosa, Enugu
The second. The published interquartile ranges around those means are wide, and outcomes like yours are well within them. The trials were not designed to explain why some people hold weight after cessation and others do not, and nothing measured at randomisation predicts it usefully. You are not an anomaly; you are part of a distribution nobody quotes.
On “Why people actually stop, in the order they actually stop” — The Ledger, 8 Jul 2024
You describe the maintenance strategy of stepping down one dose and holding for eight to twelve weeks as something clinicians report doing, and then say it is not a recommendation. That distinction will be lost on most readers, and printing the protocol makes you a source for it whether you intend to be or not.
— E. Vandenberghe, Ghent
This is the hardest editorial question this department faces and we do not think you are wrong. Our position is that a practice this widespread is better described accurately, with its evidentiary status stated, than left to circulate in fragments. We accept that the distinction does work that a reader may not do.
On “Why people actually stop, in the order they actually stop” — The Ledger, 8 Jul 2024
I lost access for eleven weeks during the shortage, restarted at the dose I had been on because nobody told me otherwise, and spent a fortnight unable to keep food down. I had been on that dose for seven months without difficulty. Reading your resumption section was the first time anybody explained it.
— N. Bujanović, Sarajevo
It is entirely predictable from the label and the pharmacokinetics, and the failure to communicate it during the shortage period was systemic rather than individual. We are sorry it reached you this way and we are glad it reached you.
On “Why people actually stop, in the order they actually stop” — The Ledger, 8 Jul 2024
Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.
— S. Tovmasyan, Gyumri
Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.
On “Glass, elastomer, aluminium: a three-material argument about one closure” — Laboratory Notebook, 8 Jul 2024
You write that recombinant factor C is insensitive to the glucan branch of the cascade. It would be worth adding why anybody cares: cellulose filter media and certain paper wrappings shed glucans, and a laboratory that has chased a false positive through three repeat assays will never willingly go back to a reagent that responds to them.
— P. Hollingsworth, Norwich
On “Glass, elastomer, aluminium: a three-material argument about one closure” — Laboratory Notebook, 8 Jul 2024
Your endotoxin table gives vial 12 at 112 EU per vial and then declines to say whether that is dangerous. I understand why. It is still frustrating to read a figure of that size next to the sentence "arithmetic, not a safety assessment".
— F. Okonjo, Asaba
We understand the frustration and we are going to keep doing it. The figure sits at roughly a third of the hourly systemic allowance for a 70 kg adult if the whole vial were administered at once, which is a comparison a reader can make. What we cannot do is turn a single determination on one vial into a statement about a person, and pretending otherwise would be the more serious failure.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 7 Jul 2024
I lost access for eleven weeks during the shortage, restarted at the dose I had been on because nobody told me otherwise, and spent a fortnight unable to keep food down. I had been on that dose for seven months without difficulty. Reading your resumption section was the first time anybody explained it.
— Q. Delacroix, Montréal, QC
It is entirely predictable from the label and the pharmacokinetics, and the failure to communicate it during the shortage period was systemic rather than individual. We are sorry it reached you this way and we are glad it reached you.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 7 Jul 2024
Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.
— P. Sandoval, Albuquerque, NM
Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 7 Jul 2024
I stopped eight months ago after reaching a weight I was happy with, and I have regained four of the twenty-two kilograms I lost. Every article I read told me to expect two-thirds back. I am not complaining, but I would like to know whether I am unusual or whether the two-thirds figure was always a mean concealing an enormous range.
— T. Aoyama, Nagoya
The second. The published interquartile ranges around those means are wide, and outcomes like yours are well within them. The trials were not designed to explain why some people hold weight after cessation and others do not, and nothing measured at randomisation predicts it usefully. You are not an anomaly; you are part of a distribution nobody quotes.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 7 Jul 2024
You describe the maintenance strategy of stepping down one dose and holding for eight to twelve weeks as something clinicians report doing, and then say it is not a recommendation. That distinction will be lost on most readers, and printing the protocol makes you a source for it whether you intend to be or not.
— S. Weatherall, Newcastle, NSW
This is the hardest editorial question this department faces and we do not think you are wrong. Our position is that a practice this widespread is better described accurately, with its evidentiary status stated, than left to circulate in fragments. We accept that the distinction does work that a reader may not do.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 7 Jul 2024
Three months after stopping, my HbA1c had barely moved and I concluded I had got away with it. Six months after stopping, it was back where it started. Your point about the lag is the single most useful sentence I have read on this subject.
— T. Blakemore, Hull
On “From vial to bench: what is recorded and what is assumed” — The Supply Chain, 5 Jul 2024
I submitted a vial to one of these services last year, got a result three points below what the vendor advertised, and did not know what to do with it. Your article explains why: I had one measurement on one vial, no method comparison, and no way to know if my vial was representative. I still do not know what to do with it, but I understand the shape of not knowing.
— E. Sørheim, Stavanger
That is a better summary of this article’s practical content than our own closing paragraphs. The one thing we would add is that your result is worth publishing wherever you can, because buyer-submitted results are the scarcest and most informative category in the entire corpus.
On “From vial to bench: what is recorded and what is assumed” — The Supply Chain, 5 Jul 2024
I run analytical services and I object to the framing of your blind comparison. You bought our cheapest tier, published the number it produced alongside a competitor’s most thorough package, and called the result a spread. It is not a spread. It is three different products, priced accordingly, and your own table says so two columns to the right of the headline figure.
— H. Steinmetz, Basel
This is the objection we thought was most likely and we think it is partly right. The comparison is of standard products at standard prices, which is what buyers actually purchase, and we said so. But the presentation invites the reading you object to, and the figure caption now states the tier alongside each result rather than leaving it to the method columns.
On “From vial to bench: what is recorded and what is assumed” — The Supply Chain, 5 Jul 2024
You note that no service offers sterility testing and that it takes fourteen days. Worth saying more plainly: a purity certificate and a sterility assurance are not merely different tests, they are different disciplines with different facilities, and no amount of chromatography will ever bear on it.
— C. Tremonti, Palermo
Correct and worth the emphasis. We have said it in the certificates piece and should say it here too: nothing any of these four services sells addresses sterility, endotoxin or container closure integrity, and no combination of their reports adds up to one.
On “From vial to bench: what is recorded and what is assumed” — The Supply Chain, 5 Jul 2024
The price table is the most useful thing you have published this year and also the thing most likely to be quoted out of context by somebody selling a comparison service. You might consider a note.
— G. Thorbjørnsen, Tromsø
There is one, and we have strengthened it. The figures are what this publication was invoiced at list rates and are not quotations a reader should expect; volume submitters pay materially less.
On “From vial to bench: what is recorded and what is assumed” — The Supply Chain, 5 Jul 2024
As a buyer I found the section on who chose the vial genuinely clarifying and slightly deflating. I have been treating vendor-published reports as equivalent to my own submissions for two years, and on your account they are not equivalent by an amount that cannot be measured.
— P. Havlíček, Brno
That is the correct reading, and the unmeasurable part is the honest part. We would add only that vendor-published reports are not worthless — a vendor willing to commission testing at all is behaving better than one that will not — they are simply weaker in a specific way.
On “Pass, conform, comply: three words for three different claims” — Explainers, 4 Jul 2024
The composite test table you print as a model is unrealistic. No research supplier is going to run headspace GC and ion chromatography on every lot at these price points, and publishing an aspirational document as a benchmark just makes real certificates look worse than they are.
— R. Mothibi, Gaborone
The table note says explicitly that no supplier in our programme issues a document containing every row, and it is offered as a reference rather than as a demand. But you have a point about framing, and we have moved the caveat from the note into the caption.
On “Reading the dulaglutide titration schedule as a regulatory artefact” — Pharmacology, 4 Jul 2024
I want to object to the framing of dose reduction as measurement. In practice it is experienced as failure, and telling people it is a thermostat does not change how the appointment feels. The language problem is real and you have solved it rhetorically rather than actually.
— B. Tejeda, Santo Domingo
A fair hit. We can describe the pharmacology accurately and still be writing at a distance from how the decision lands, and the paragraph you object to does both. The reframing is offered as a corrective to a stigma, not as a claim that the stigma is imaginary.
On “The convention nobody explains before handing over the vial” — Patient Notes, 2 Jul 2024
Nothing in this file addresses what to do when you realise mid-week that you have made an error. I gave double my dose on a Sunday and could find no guidance anywhere about what that meant.
— H. Fitzmaurice, Preston
A real gap and we will address it properly rather than in a reply. The short version is that it is a pharmacokinetic question — how much excess exposure, over what half-life — and a clinical one about symptom burden, and neither is answerable in the abstract. It also belongs in the titration file, which currently discusses omission and not excess.
On “The convention nobody explains before handing over the vial” — Patient Notes, 2 Jul 2024
I gave myself a tenth of my intended dose for five weeks. I had been using insulin syringes, ran out, and used the 1 mL syringes that came with the vials, which are marked in millilitres. I did not notice because the plunger was in roughly the same place. Nobody warned me these were different scales.
— B. Sundqvist, Turku
This is the error we rank first for magnitude and we are grateful for the account, because it happened exactly as the mechanism predicts: a substitution that produced no visible signal. The one structural defence is to buy syringes deliberately and keep to a single type rather than using whatever arrives in the parcel.
On “The convention nobody explains before handing over the vial” — Patient Notes, 2 Jul 2024
Your needle-length section says four millimetres is adequate for all adults, which contradicts what I was told by a nurse who insisted on half an inch because of my weight. Which is right?
— J. Prendergast, Wollongong, NSW
The published recommendations are with us, and the reason is that skin thickness varies remarkably little with body mass while subcutaneous fat varies enormously. A longer needle in a heavier person is not more likely to reach the right layer; it is only more likely to go past it in a thinner limb. We would put the ultrasound measurement studies in front of your nurse rather than argue from authority.
On “Seasonal use, holiday use, and the honest state of the evidence” — Clinical Trials, 1 Jul 2024
I take this for kidney disease, not for weight. Every piece of writing I encounter about stopping is about the weight coming back. It has taken me a year to find anybody willing to say plainly that the renal benefit accrued over years of treatment and nobody has tested what happens if I stop.
— D. Ferreira-Lopes, Porto
On “Seasonal use, holiday use, and the honest state of the evidence” — Clinical Trials, 1 Jul 2024
The claim that stopping does not leave you worse off than baseline is a group-level claim about trial arms. Individuals can and do overshoot. Your phrasing invites readers to conclude otherwise.
— A. Petrucci, Bari
Correct, and the distinction matters. We have added a clause: no arm overshot at a group level, which is not the same as no participant overshooting. The trials do not report individual overshoot rates and we have not found them published anywhere.
On “Seasonal use, holiday use, and the honest state of the evidence” — Clinical Trials, 1 Jul 2024
Three months after stopping, my HbA1c had barely moved and I concluded I had got away with it. Six months after stopping, it was back where it started. Your point about the lag is the single most useful sentence I have read on this subject.
— B. Ademola, Ilorin
On “The out-of-range flag is a statistical convention with a printer attached” — Laboratory Notebook, 29 Jun 2024
My eGFR has risen from 71 to 84 over fourteen months of treatment and I have lost twenty-six kilograms. My prescriber described this as the drug protecting my kidneys. Having read your creatinine section, I suspect it is mostly that I have less muscle. Which of us is right?
— L. Marulanda, Medellín
On the information given, probably you, at least in part. A rise of that size during weight loss of that magnitude is well within what reduced creatinine production can produce. A cystatin C-based estimate alongside the creatinine one would separate the two, and is the measurement worth asking for. It is also possible both things are happening.
On “The out-of-range flag is a statistical convention with a printer attached” — Laboratory Notebook, 29 Jun 2024
I stopped treatment fifteen weeks ago and my panel is worse than I expected. I had a panel at five weeks that looked fine and I had assumed I had escaped. Your point about the twelve-week timing was the explanation nobody offered me.
— P. Vuković, Split
On “The out-of-range flag is a statistical convention with a printer attached” — Laboratory Notebook, 29 Jun 2024
As a biomedical scientist I would add one point to your reference-interval section: many laboratories do not derive their own intervals at all. They adopt the manufacturer interval for the platform, which was established in a population that may have nothing to do with the one being tested. The interval on the report can be a document about a different country.
— R. Mothibi, Gaborone
This is correct, common, and something we should have stated. We have added it, and it strengthens rather than weakens the argument for within-person comparison.
On “The out-of-range flag is a statistical convention with a printer attached” — Laboratory Notebook, 29 Jun 2024
You give the reference change value for ALT as about sixty per cent, which strikes me as so large as to make routine monitoring of it pointless. Is that your position?
— R. Sundaresan, Coimbatore
Not quite. It makes monitoring for small movements pointless, which is different. A doubling is well outside the RCV and is a real signal; a rise from 28 to 41 is not. The value of the test lies in detecting the former, and much of the anxiety it generates comes from acting on the latter.
On “Why people actually stop, in the order they actually stop” — Patient Notes, 28 Jun 2024
Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.
— S. Ó Ceallaigh, Limerick
Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.
On “Why people actually stop, in the order they actually stop” — Patient Notes, 28 Jun 2024
I lost access for eleven weeks during the shortage, restarted at the dose I had been on because nobody told me otherwise, and spent a fortnight unable to keep food down. I had been on that dose for seven months without difficulty. Reading your resumption section was the first time anybody explained it.
— R. Cadogan, Bridgetown
It is entirely predictable from the label and the pharmacokinetics, and the failure to communicate it during the shortage period was systemic rather than individual. We are sorry it reached you this way and we are glad it reached you.