Every letter we have printed
Page 60 of 77 of this archive, newest first.
On “Grams per kilogram of what? The denominator problem in protein guidance” — Clinical Trials, 4 Aug 2024
Small correction to your table: the S-LiTE exercise prescription was two supervised group sessions and two individual sessions weekly, not two sessions in total. The distinction matters because "add some exercise" is not what was tested.
— F. Aubert, Toulouse
Correct, and that is precisely the point we were trying to make and then undermined in our own table. Amended.
On “Four ways a peptide comes apart” — Laboratory Notebook, 3 Aug 2024
You say no company reports residual moisture. I obtained a figure from a supplier last year without difficulty, on request, so the data exists in at least some cases. The problem may be less that it is not measured than that it is not printed.
— C. Aguirre, Rosario
On “Four ways a peptide comes apart” — Laboratory Notebook, 3 Aug 2024
I have shipped temperature-sensitive material commercially for eleven years and your coolant arithmetic is right but generous. You assume the pack starts fully frozen. In practice packs are pulled from a freezer that is opened forty times a day, and a pack that starts at minus four with a soft core has lost a fair share of its budget before the box is closed.
— G. Rasmussen, Odense
A good point and one we had not considered properly. The latent heat calculation assumes a fully solid pack at its melting point, and a partially thawed pack is exactly as much worse as the missing solid fraction. We have added a sentence and would welcome any data you can share on pack condition at packing.
On “Four ways a peptide comes apart” — Laboratory Notebook, 3 Aug 2024
Your table of degradation pathways lists racemisation and then says it is essentially never reported. If it is never reported, on what basis do you list it as a real risk rather than a theoretical one?
— E. Nkomo, Polokwane
On the basis of the synthesis and analytical literature, where epimer formation during solid-phase assembly and during storage at extremes of pH is well characterised. What is missing is not evidence that it occurs but evidence about how much of it is present in any particular commercial vial, which is a different absence and the one we should have named.
On “Two decimal places on a single injection is a rhetorical choice” — Explainers, 2 Aug 2024
You describe reused chromatogram images as a tell. I work in a contract laboratory and I would note that some data systems export a representative overlay rather than the individual injection, so identical-looking traces can occur legitimately across a batch series. It is still worth asking about; it is not the smoking gun your article implies.
— N. Prasetyo, Surabaya
A useful qualification and the text has been softened. The observation remains worth making; the inference we drew from it was stronger than the practice supports.
On “Two decimal places on a single injection is a rhetorical choice” — Explainers, 2 Aug 2024
Your ten-minute check told me in about ninety seconds that the batch number on my certificate appears nowhere on the vial. I wrote to the supplier and had a straightforward answer within a day: the certificate covers the bulk lot and the vial carries a fill code. I would never have known to ask.
— V. Bhattarai, Kathmandu
That is exactly the intended use, and the supplier’s answer is the correct one. The remaining question is why the relationship between the two codes is not printed on the document, since it takes a line.
On “Two decimal places on a single injection is a rhetorical choice” — Explainers, 2 Aug 2024
I supply research peptides and I want to push back on the specification column point. We sell from a catalogue of six hundred products. Writing a meaningful individual specification for each would take a year of somebody’s time, and a generic one would be exactly the decorative limit your article criticises. What would you actually have us do?
— P. Sarkissian, Beirut
A fair challenge. Our answer is that a generic limit stated honestly is better than no limit at all, provided the typical result is also published so a reader can see the margin. What we object to is a decorative limit presented as a control. Publishing your process capability alongside it removes the objection entirely, and costs you a spreadsheet.
On “Two decimal places on a single injection is a rhetorical choice” — Explainers, 2 Aug 2024
The most useful sentence in the piece is the one saying a bad document is not a bad product. I have spent two years on forums watching people conclude the opposite from a missing signature block, and it has made the whole conversation about honesty rather than about paperwork.
— J. Delahunty, Waterford
That inversion is the reason we wrote the final section, and we would rather be accused of excessive caution than contribute to it.
On “Stepping down is part of titration” — Pharmacology, 2 Aug 2024
You describe the plateau as an energy-balance event and dismiss receptor desensitisation. Is there not a third possibility — that adherence quietly falls off at around a year and the plateau is partly a behavioural artefact of the trial rather than a physiological one?
— H. Ravensworth, York
There is, and it is a better objection than the desensitisation argument. Adherence does decline over the second year of the long programmes, and the treatment-policy analyses absorb that decline into the mean. We should have said that the plateau is very likely a composite of energy balance and falling adherence, in proportions the published analyses do not separate cleanly.
On “Stepping down is part of titration” — Pharmacology, 2 Aug 2024
The claim that nobody has randomised escalation intervals is too strong. There are protocol amendments in several programmes that effectively created slower-titration cohorts, and some of those have been analysed post hoc.
— E. Marchetti, Bologna
Post-hoc comparison of cohorts created by amendment is not randomisation, and treating it as such is exactly the elision we were objecting to. We accept that such analyses exist and are informative; we maintain that they cannot settle the question, and the file now says so in those terms.
On “Stepping down is part of titration” — Pharmacology, 2 Aug 2024
A small thing. You give the semaglutide diabetes ladder as ending at 2.0 mg and the weight ladder at 2.4 mg, without explaining why the same molecule has two ceilings for two indications. It looks arbitrary and I suspect it is not.
— L. Dziedzic, Wrocław
It is not arbitrary — the two maxima come from separate dose-selection programmes with different primary endpoints, and 2.0 mg was established against 1.0 mg in a dedicated glycaemic comparison. We have added a clause. The underlying point, that indication shapes the ladder as much as the molecule does, is worth more space than we gave it.
On “Stepping down is part of titration” — Pharmacology, 2 Aug 2024
I had a nine-week gap last year because my supplier stopped answering messages. Nobody in any clinical setting I dealt with treated that as a pharmacological event. Your framing of supply interruption as a dosing decision is the first time I have seen it written down.
— E. Beauchamp, Ottawa, ON
On “Stepping down is part of titration” — Pharmacology, 2 Aug 2024
You keep insisting on peptide content rather than purity when discussing dose certainty. I have looked at a dozen certificates from four different testing services and content is reported on perhaps a third of them. What are readers supposed to do with an absence?
— B. Wojciechowski, Kraków
Treat the nominal figure as an upper bound and say so out loud when reasoning about a dose. It is an unsatisfying answer and it is the honest one. We have argued in Analytics that content should be a standard reported field, and we will keep naming the services that report it and those that do not.
On “The badge economy, and what it is actually certifying” — The Ledger, 1 Aug 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.
— A. Mbeki, Lusaka
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 “The badge economy, and what it is actually certifying” — The Ledger, 1 Aug 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.
— D. Mazzarella, Catania
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 “The badge economy, and what it is actually certifying” — The Ledger, 1 Aug 2024
Your suggestion that laboratories publish the fact of a submission while keeping the result confidential is the first proposal I have read in this area that a laboratory could actually implement without breaching a client obligation. I have raised it internally.
— C. Rautenbach, Pretoria
We would be glad to report the outcome either way, including if the answer is no and the reason is commercial. The proposal is only useful if somebody adopts it, and a published refusal is more informative than silence.
On “What a split-sample exercise can establish, and what it cannot” — The Supply Chain, 30 Jul 2024
Your selection-effect model assumes a supplier publishes results above a fixed threshold. Real behaviour is surely more complicated: a supplier might publish a poor result on a batch it has withdrawn, or publish everything for a period to establish credibility and then stop. The arithmetic is fine and the behavioural assumption is a cartoon.
— J. Kettleborough, Nottingham
Agreed, and the figure caption now says illustrative arithmetic rather than model. The point survives the simplification, which is that a small amount of selection produces a large apparent effect, but we should not have dressed a demonstration as an estimate.
On “What a split-sample exercise can establish, and what it cannot” — The Supply Chain, 30 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.
— C. Nightingale, Plymouth
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 “What a split-sample exercise can establish, and what it cannot” — The Supply Chain, 30 Jul 2024
You disclose that two of these services advertise with you and then spend four thousand words on structural criticism of the sector they operate in. I cannot decide whether that is admirable independence or an elaborate way of appearing independent. Probably the former. I wanted to say that I noticed the question.
— J. Mbatha, Durban
So do we, every time this department writes about the sector. The only answers we have are procedural: the disclosure, the standards desk edit, the consulting prohibition on the writer, and the practice of printing objections like yours unedited.
On “The interventions with trial support, and the much longer list without” — Pharmacology, 29 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?
— B. Osei-Bonsu, Kumasi
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 interventions with trial support, and the much longer list without” — Pharmacology, 29 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.
— L. Kowalski, Gdańsk
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 interventions with trial support, and the much longer list without” — Pharmacology, 29 Jul 2024
Nothing in your file addresses the social dimension, which for me was worse than the nausea. Six months of declining invitations to meals, and explaining to family why I was not eating. The tables do not have a row for that.
— M. Halim, Kuala Lumpur
On “What a 1 mL syringe does that a 0.3 mL syringe does not” — Patient Notes, 27 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.
— J. Vasilenko, Chisinau
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 “What a 1 mL syringe does that a 0.3 mL syringe does not” — Patient Notes, 27 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.
— K. Sivertsen, Bergen
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 “What a 1 mL syringe does that a 0.3 mL syringe does not” — Patient Notes, 27 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?
— S. Bergqvist, Malmö
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 “How a claim degrades between the bench and the listing” — The Ledger, 27 Jul 2024
Your selection-effect model assumes a supplier publishes results above a fixed threshold. Real behaviour is surely more complicated: a supplier might publish a poor result on a batch it has withdrawn, or publish everything for a period to establish credibility and then stop. The arithmetic is fine and the behavioural assumption is a cartoon.
— E. Thistlethwaite, Sheffield
Agreed, and the figure caption now says illustrative arithmetic rather than model. The point survives the simplification, which is that a small amount of selection produces a large apparent effect, but we should not have dressed a demonstration as an estimate.
On “How a claim degrades between the bench and the listing” — The Ledger, 27 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.
— V. Petrosyan, Yerevan
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 “How a claim degrades between the bench and the listing” — The Ledger, 27 Jul 2024
You disclose that two of these services advertise with you and then spend four thousand words on structural criticism of the sector they operate in. I cannot decide whether that is admirable independence or an elaborate way of appearing independent. Probably the former. I wanted to say that I noticed the question.
— A. Salcedo, Bilbao
So do we, every time this department writes about the sector. The only answers we have are procedural: the disclosure, the standards desk edit, the consulting prohibition on the writer, and the practice of printing objections like yours unedited.
On “How a claim degrades between the bench and the listing” — The Ledger, 27 Jul 2024
Your suggestion that laboratories publish the fact of a submission while keeping the result confidential is the first proposal I have read in this area that a laboratory could actually implement without breaching a client obligation. I have raised it internally.
— H. Nakagawa, Fukuoka
We would be glad to report the outcome either way, including if the answer is no and the reason is commercial. The proposal is only useful if somebody adopts it, and a published refusal is more informative than silence.
On “The supply gap as a clinical event” — Patient Notes, 26 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.
— P. Vuković, Split
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 “Retest date, expiry date, and the two conventions being confused” — The Supply Chain, 25 Jul 2024
I supply research peptides and I want to push back on the specification column point. We sell from a catalogue of six hundred products. Writing a meaningful individual specification for each would take a year of somebody’s time, and a generic one would be exactly the decorative limit your article criticises. What would you actually have us do?
— C. Bąkowski, Łódź
A fair challenge. Our answer is that a generic limit stated honestly is better than no limit at all, provided the typical result is also published so a reader can see the margin. What we object to is a decorative limit presented as a control. Publishing your process capability alongside it removes the objection entirely, and costs you a spreadsheet.
On “Retest date, expiry date, and the two conventions being confused” — The Supply Chain, 25 Jul 2024
The most useful sentence in the piece is the one saying a bad document is not a bad product. I have spent two years on forums watching people conclude the opposite from a missing signature block, and it has made the whole conversation about honesty rather than about paperwork.
— D. Sakamoto, Kobe
That inversion is the reason we wrote the final section, and we would rather be accused of excessive caution than contribute to it.
On “Retest date, expiry date, and the two conventions being confused” — The Supply Chain, 25 Jul 2024
A technical query on your identity row: you specify 4111.1 Da monoisotopic with a tolerance of ±10 ppm, which is 0.04 daltons. Is that not tighter than most contract laboratories will commit to on a peptide of that size?
— R. Ekwueme, Awka
It is achievable on an orbital trap with internal calibration and is tight for a quadrupole time-of-flight on external calibration. The row is drawn from a real certificate issued by a laboratory running the former. We should have said so, and the note now does.
On “The incretin receptors, ranked by how much we actually know about them” — Explainers, 24 Jul 2024
Your piece states that moving the injection day does not change total exposure, and I accept the arithmetic, but I want to record that it changed my experience considerably. I moved from Monday morning to Thursday evening and the two worst days now fall on a weekend. The drug is doing the same thing; my week is not.
— T. Nkemelu, Port Harcourt
This is exactly the distinction we were trying to draw and evidently drew badly. Total exposure is unchanged; the phase relationship between peak concentration and your working week is not. We have added a sentence to that effect.
On “Discontinuation rates, read honestly” — Pharmacology, 24 Jul 2024
I want to push back on the ginger paragraph. You describe the evidence as transferred from pregnancy and chemotherapy, which is accurate, and then include it in the table anyway. Either it belongs or it does not.
— Y. Sasaki, Sapporo
It belongs, labelled. The table is a map of what is recommended and on what basis, not a list of endorsements, and excluding widely used low-risk measures because their evidence is transferred would make the map less useful rather than more honest. We have made the column heading clearer.
On “Two sessions a week, and the evidence behind the prescription” — Laboratory Notebook, 23 Jul 2024
Your piece treats the one-quarter rule as discredited and then quotes fractions of one third and two fifths from the substudies as though those were more solid. They are group means from a hundred and forty people. Physician, heal thyself.
— L. Whitcombe, Christchurch
A fair hit, and we have amended the paragraph to carry the same caveat in both places. The distinction we should have drawn is that the substudy figures are at least attached to a stated population and a stated instrument, which the textbook rule is not. Neither is a constant.
On “Two sessions a week, and the evidence behind the prescription” — Laboratory Notebook, 23 Jul 2024
I train four times a week, eat a hundred and sixty grams of protein and my appendicular lean mass has fallen by 1.8 kg over ten months while every lift has gone up. Your section on mass against function was the first thing I have read that made that seem normal rather than a failure.
— J. Mbatha, Durban
On “Two sessions a week, and the evidence behind the prescription” — Laboratory Notebook, 23 Jul 2024
As a DXA technologist of twenty-two years I would add one thing to your precision section: the largest source of error in practice is not the machine, it is positioning. A patient scanned with their arms two centimetres further from their trunk will report different regional values. We are trained to a protocol and the protocol is not always followed.
— C. Nightingale, Plymouth
We should have said this and did not. It also argues for what you presumably practise: same device, same technologist, same protocol, and a note in the record when any of those changes.
On “Two sessions a week, and the evidence behind the prescription” — Laboratory Notebook, 23 Jul 2024
You write that no trial has measured strength. There are observational cohorts with grip strength data. Why do you insist on randomised measurement?
— J. Kettleborough, Nottingham
Because grip strength in an observational cohort of people who chose to take a drug, and who differ from those who did not in age, motivation and comorbidity, cannot separate the drug effect from the selection. We report those cohorts and we do not treat them as answering the question.
On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 22 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.
— H. Ravensworth, York
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.