JFitzgibbon

TL2 Member · Valladolid, ES

Keeps a personal log and shares the numbers when they are relevant, with the measurement caveats attached.

Joined 21 September 2025 · last posted 5d

86 posts, newest first. Showing up to 150.

Journal club: orforglipron phase 2 and the non-peptide question Replied, post #129 · Evidence › Journal club · 23 Jul 2026 · 28 likes Counterpoint on orforglipron phase 2, offered without confidence: the same observation is consistent with a much duller explanation, and nobody has ruled the dull one…
Documenting a supplier's response to a discrepancy Replied, post #43 · Sourcing › Vendor reports · 20 Jul 2026 · 23 likes Picking up post #42: that is the part I would want checked first. Blind submission is worth the effort: have someone else relabel the sample so neither you nor the…
Revisiting: Journal club: SURMOUNT-OSA and a hard endpoint in a soft field Replied, post #119 · Evidence › Journal club · 19 Jul 2026 · 12 likes Where the group cannot agree, record the disagreement rather than resolving it by seniority. The recorded disagreement is more honest and more useful later. The…
Revisiting: How this community labels and discusses unrefereed work Replied, post #27 · Evidence › Preprints · 17 Jul 2026 · 29 likes I had written a reply contradicting post #26 and deleted it. Here is what survived. Two sentences on community labels and then I will stop, because the rest is…
Stepping down deliberately, and how to do it without losing progress — what changed since Replied, post #64 · Practice › Dosing & titration · 14 Jul 2026 · 0 likes Going back down a step is not a failure and the trials allowed it. Several protocols permitted a return to the previous dose for tolerability and then a second attempt…
Reading order for a first week here, and what to skip until later — what changed since Replied, post #36 · Start Here › Welcome · 12 Jul 2026 · 32 likes Marking my uncertainty on Reading order explicitly. I am confident about the direction, much less confident about the size, and not confident at all that it generalises…
A widely repeated interaction claim that turns out to be unsupported — what changed since Replied, post #83 · Practice › Interactions · 11 Jul 2026 · 11 likes Anyone asking an interaction question should list everything, including the things they consider irrelevant. The irrelevant one is the answer more often than chance…
Osteoarthritis and mechanical versus metabolic improvement — one year on Replied, post #15 · Clinical › Comorbidities · 10 Jul 2026 · 0 likes Osteoarthritis and mechanical versus metabolic is a question about a distribution, not about a value, and treating it as a value is what produces the confident wrong…
Prior authorisation: what the criteria usually require — a second dataset Replied, post #7 · Access › Insurance & coverage · 7 Jul 2026 · 4 likes The arithmetic in post #4 is right; the assumption feeding it is the part to check. Date every account in this subcategory. Payer criteria change frequently and the…
I joined for one answer and stayed for a year — what changed my mind Replied, post #41 · Start Here › Welcome · 25 Jun 2026 · 0 likes One thing that took me a while to notice: the search box indexes maintained documents as well as topics, and documents carry a review date. If a document and a…
Preservatives: function, testing, and limits — one year on Replied, post #26 · Pharmacology › Formulation chemistry · 23 Jun 2026 · 0 likes The reason Preservatives keeps being re-asked is that the answer is conditional and people quote it without the condition. It is not that the answer is unknown.
Journal club: orforglipron phase 2 and the non-peptide question Replied, post #99 · Evidence › Journal club · 22 Jun 2026 · 0 likes The baseline characteristics table is the single most useful page for the questions that get asked here, because it tells you who the result applies to. I would not…
Injecting into an area that has become firm: why not to Replied, post #56 · Practice › Administration · 12 Jun 2026 · 7 likes Grateful for the specificity. Vague answers to this question are what sent me looking.
Asking a follow-up: new topic or new reply? Replied, post #7 · Start Here › How to Ask · 11 Jun 2026 · 7 likes A photograph of a vial is rarely useful and a photograph of a document usually is. Redact the identifiers before you post either.
Personal or family history of medullary thyroid carcinoma — what changed since Replied, post #58 · Safety › Contraindications · 1 Jun 2026 · 0 likes Somebody's condition being on a list does not settle the decision, and somebody's condition being absent from one does not either.
Semaglutide and gastric emptying — the mechanism behind most of the side-effect profile Replied, post #36 · Compounds › Semaglutide · 23 May 2026 · 0 likes Picking up post #35: that is the part I would want checked first. Discontinuation rates in the trials are worth reading alongside efficacy and almost never are. A large…
Prescription requirements and telehealth models — a second dataset Replied, post #32 · Sourcing › Regulatory · 17 May 2026 · 0 likes Picking up post #29: that is the part I would want checked first. The reason Prescription requirements and telehealth models is hard to answer is that the obvious…
Why fasting instructions for oral semaglutide are not optional advice Replied, post #4 · Compounds › Oral incretins · 15 May 2026 · 5 likes PIONEER 6 was a cardiovascular safety trial for oral semaglutide, not an efficacy trial. Non-inferiority for safety was demonstrated. The point estimates favoured the…
[2026 update] 0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #115 · Devices › Syringes & needles · 13 May 2026 · 32 likes Small correction to my own earlier position on 0.3 ml versus 0.5 ml. I had the units the wrong way round, which changes the conclusion by an order of magnitude and…
Revisiting: Absolute versus relative contraindications Replied, post #84 · Safety › Contraindications · 7 May 2026 · 30 likes The arithmetic in post #81 is right; the assumption feeding it is the part to check. I have been on both sides of the Absolute versus relative contraindications…
Reference intervals: how they are constructed and why one in twenty flags Replied, post #80 · Clinical › Bloodwork · 13 Apr 2026 · 6 likes Where I part company with post #76, and it is a narrow parting. One more thing on reference intervals that took me far too long to see: the two figures people quote are…
Bug report: the reconstitution calculator and a rounding edge case Replied, post #50 · Data & Tools › Calculators · 8 Apr 2026 · 12 likes A calculator that shows its working is worth ten that give an answer. The whole value is being able to see which step you disagree with. Filing this under things that…
Whether an aggregate is worth publishing at all: a disputed topic — does this still hold? Replied, post #13 · Data & Tools › Datasets · 8 Apr 2026 · 0 likes The reason Whether an aggregate keeps being re-asked is that the answer is conditional and people quote it without the condition. It is not that the answer is unknown.
Which panel is worth repeating and which is worth ignoring — a second dataset Replied, post #102 · Clinical › Bloodwork · 16 Mar 2026 · 11 likes Adding the measurement that post #99 says would settle it. The arithmetic on panel is the easy part and it is where the errors are, which is an uncomfortable…
Shoulders, tangent skims, and defensible integration — the long version Replied, post #16 · Analytics › HPLC & UHPLC · 13 Mar 2026 · 9 likes Good question, well framed, and I would like to see it answered properly.
Grapefruit: why this class is not the class that cares Replied, post #35 · Practice › Interactions · 13 Mar 2026 · 26 likes The number people quote for grapefruit is a central estimate presented without its interval, and the interval is wide enough that the estimate is nearly uninformative…
Reading U-100 graduations, with a conversion table — one year on Replied, post #6 · Devices › Syringes & needles · 12 Mar 2026 · 7 likes Reusing a needle blunts it and there is no benefit to offset that. The second injection with the same needle is the one people describe as painful. Written in the hope…
Publication bias detection and its low power — does this still hold? Replied, post #16 · Evidence › Meta-analyses · 8 Mar 2026 · 0 likes Where I part company with post #15, and it is a narrow parting. Reading the pooled figure without reading the inclusion criteria is the equivalent of quoting a trial…
Choosing which test to pay for, given a fixed budget Replied, post #14 · Sourcing › Independent verification · 5 Mar 2026 · 2 likes Cross-checking one lot with two services independently is the cleanest test available and is rarely done because it costs twice as much. I have deliberately not rounded…
Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #131 · Compounds › Semaglutide · 28 Feb 2026 · 32 likes The 165 to 184 hour half-life range gets quoted as a fixed number. It is a range across a studied population, and individual clearance varies enough that a person's own…
Stepping down deliberately, and how to do it without losing progress Replied, post #59 · Practice › Dosing & titration · 16 Feb 2026 · 31 likes Useful. I had the fact and not the reason, which turns out to be the important half.
Second pass at: The topic list is dense — is that deliberate? Replied, post #52 · Meta › Site feedback · 24 Jan 2026 · 0 likes Careful with the language on topic list. "Not detected" and "not present" are different findings and the first is a statement about the method.
Why the titration planner refuses to produce a schedule below a floor Replied, post #29 · Data & Tools › Calculators · 17 Jan 2026 · 0 likes Narrowing post #28, because the general version has more than one answer. Significant figures in the output should not exceed what the inputs support. A concentration…
What "marked as solution" means and who gets to mark it — does this still hold? Replied, post #28 · Start Here › Welcome · 6 Jan 2026 · 0 likes You do not need to introduce yourself before asking a question, and nobody will think worse of you for arriving with one. The introductions subcategory exists for…
Why an oral GLP-1 agonist is a formulation achievement more than a chemistry one Replied, post #122 · Compounds › Oral incretins · 1 Jan 2026 · 25 likes Where I part company with post #120, and it is a narrow parting. Tablet integrity matters more than people expect for a formulation that depends on an absorption…
"Greater than or equal to 99%" as a specification rather than a result Replied, post #94 · Analytics › COA interpretation · 21 Dec 2025 · 26 likes A certificate of analysis is a statement by its issuer that a defined test was performed on a defined lot and produced a defined result. That is all it is, and it is…
Comparing my trajectory with the trial curves, carefully Replied, post #89 · Outcomes › Progress reports · 12 Dec 2025 · 2 likes If a pattern survives a rolling-mean treatment it is worth explaining. Most do not, and that is the useful finding.
Tracking a preprint to publication: a worked example Replied, post #121 · Evidence › Preprints · 12 Dec 2025 · 13 likes Building on post #118 rather than restating it. Peer review catches some things reliably — missing methods, unsupported conclusions, statistical mistakes of the obvious…
Follow-up: The decimal-point error, and the habit that catches it Replied, post #113 · Practice › Reconstitution · 5 Dec 2025 · 20 likes Do not shake. Swirl, or leave it. Vigorous agitation introduces air and shear, and neither helps a peptide go into solution any faster than patience does. Worth saying…
What a purity-only report leaves out Replied, post #99 · Sourcing › Independent verification · 23 Nov 2025 · 16 likes A record with four results over sixteen months is a thin record rather than a bad one, and the honest description says which. That is the version I would defend. It is…
Sleep tracking data and its considerable limitations Replied, post #99 · Wellbeing › Sleep · 27 Oct 2025 · 3 likes Gastrointestinal effects overnight: nausea or reflux or constipation at night can disrupt sleep. Dosing timing (morning versus evening) might help if nighttime GI…
Reconciling a supplier certificate with an independent result Replied, post #15 · Sourcing › Vendor reports · 26 Oct 2025 · 25 likes Recording a reorder result against the original is one of the highest-value contributions here, because consistency over time is what a single result cannot show. A…
A parcel that arrived warm: a decision process, not a verdict Replied, post #102 · Practice › Storage & stability · 25 Oct 2025 · 3 likes Post #98 describes the usual case. This is about the unusual one. Visible particulate is a strong signal in the other direction: it is a reason to stop and ask rather…
Power cut for eleven hours: how I assessed it afterwards Replied, post #109 · Practice › Storage & stability · 24 Oct 2025 · 0 likes An honest declaration on power cut for eleven hours: I have a prior here and it is strong enough that you should weight what I say downward. Stating it rather than…
SURMOUNT-4 and what withdrawal data does and does not tell an individual — one year on Replied, post #37 · Compounds › Tirzepatide · 20 Oct 2025 · 1 like I changed my mind about SURMOUNT-4 after someone here asked me for the source and I could not produce one. That is worth saying out loud because it is the ordinary way…
Reconciling a supplier certificate with an independent result Replied, post #10 · Sourcing › Vendor reports · 20 Oct 2025 · 11 likes Taking post #7 at face value and following it one step further. Where you have no independent result, a documentation report is still worth filing: what the certificate…
What happens after your first post: likes, trust levels, and why none of it matters much… Replied, post #57 · Start Here › Welcome · 17 Oct 2025 · 16 likes If you are not sure which subcategory a question belongs in, post it in the closest one. A moderator will move it, the move is logged, and nothing bad happens to you. I…
MHRA statements, read directly Replied, post #5 · Regional › UK & Ireland · 19 Sep 2025 · 18 likes Where a member reports a decision, the useful detail is the stated reason rather than the outcome, because the reason is what generalises. Flagging that the sources on…
Payment method and the leverage it gives you, ranked Replied, post #22 · Sourcing › Payments · 16 Sep 2025 · 0 likes If someone has run payment method properly I would rather read that than my own reconstruction of it. Posting mine only because the thread has gone quiet.
Realistic expectations for strength while losing weight quickly Replied, post #18 · Nutrition & Training › Resistance training · 3 Sep 2025 · 0 likes The bit of realistic expectations for strength that nobody enjoys is that the answer changes depending on what you are trying to decide with it. Say what the decision…
Follow-up: The decimal-point error, and the habit that catches it Replied, post #52 · Practice › Reconstitution · 1 Sep 2025 · 17 likes What I would check first on decimal-point error is whether the thing being measured moved or whether the way of measuring it moved. Those look identical in a graph.
Fatigue in the first month: how much is the drug and how much is intake — what changed… Replied, post #43 · Practice › Side effects · 20 Aug 2025 · 9 likes The useful distinction on Fatigue is between what was measured and what was inferred from it. Both end up in the same sentence and only one of them has error bars.
Why fasting instructions for oral semaglutide are not optional advice — does this still… Replied, post #83 · Compounds › Oral incretins · 16 Aug 2025 · 1 like This is the sort of exchange that makes the archive worth searching.
[2026 update] What we do not know about retatrutide, listed explicitly Replied, post #37 · Compounds › Retatrutide · 6 Aug 2025 · 0 likes I had read the opposite somewhere and cannot now find where, which tells me something.
Second pass at: Why this subcategory is stricter about sourcing than most Replied, post #8 · Compounds › Secretagogues & GH axis · 23 Jul 2025 · 4 likes Confirming post #7 from a second method, which matters more than confirming it from a second person. Reconstitution volumes in this family are often small enough that…
A field-by-field walk through a certificate of analysis Replied, post #139 · Analytics › COA interpretation · 18 Jul 2025 · 0 likes The distinction between release testing and characterisation is one industrial documents make and retail ones usually do not. It is the difference between "we tested…
Preparing for an appointment: one page, three questions Replied, post #27 · Clinical › Prescriber conversations · 14 Jul 2025 · 0 likes If the answer is no, asking for the reason is reasonable and the reason is usually specific. It is also what makes an appeal possible where one exists. I have separated…
Coming back to: Nausea profile of amylin analogues compared with GLP-1 agonists Replied, post #32 · Compounds › Cagrilintide & amylin analogues · 9 Jul 2025 · 0 likes Building on post #30 rather than restating it. For anyone arriving from searches on "amylin agonist": this subcategory discusses published clinical evidence and what it…
Journal club: the CagriSema phase 2 combination paper — a second dataset Replied, post #56 · Evidence › Journal club · 27 Jun 2025 · 7 likes Post #54 and I disagree about the size of the effect, not about the direction. Bringing the previous paper on the same question makes the session much better and…
Promotion criteria, and the one that stops most nominations — the long version Replied, post #11 · Documentation › Doc review · 10 Jun 2025 · 4 likes A promotion that is declined should leave the topic linked from wherever the question recurs, so the work is not lost.
A certificate whose chromatogram axes do not match its stated method Replied, post #13 · Sourcing › Red flags · 10 Jun 2025 · 0 likes I had written a reply contradicting post #10 and deleted it. Here is what survived. A certificate whose lot number does not match the vial is a stop-and-ask, not a…
An emergency department visit, described afterwards Replied, post #27 · Safety › Adverse events · 3 Jun 2025 · 9 likes I changed my mind about emergency department visit after someone here asked me for the source and I could not produce one. That is worth saying out loud because it is…
Second pass at: Trial registration and comparing the protocol with the paper Replied, post #4 · Evidence › Trials · 29 May 2025 · 3 likes Where I part company with post #3, and it is a narrow parting. Effect sizes in a trial population reflect adherence achieved under trial conditions, which is generally…
Albumin binding and how it produces a long half-life Replied, post #36 · Pharmacology › Pharmacokinetics · 14 May 2025 · 11 likes Answering the question post #32 raises rather than the one it answers. A pharmacokinetic model fitted to trial data describes the population studied. Applying it to…
Antibiotics and a course of something with delayed emptying Replied, post #41 · Practice › Interactions · 14 May 2025 · 7 likes Where I part company with post #37, and it is a narrow parting. Adding the boring version of antibiotics, because the interesting version keeps getting posted and the…
A well-designed study with a badly written abstract Replied, post #64 · Evidence › Study critique · 6 May 2025 · 2 likes The confident answers on well-designed study and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.
Second pass at: Retatrutide mass and identity: what a report should show Replied, post #28 · Compounds › Retatrutide · 24 Apr 2025 · 21 likes Taking post #27 at face value and following it one step further. No phase 3 results exist for retatrutide. Anything attributed to a completed phase 3 trial of this…
Second pass at: A history of disordered eating: proceeding carefully Replied, post #20 · Wellbeing › Mental health · 18 Mar 2025 · 22 likes That is clearer than the version I had in my head. Thank you.
Requesting a page: what makes a good request Replied, post #27 · Documentation › Wiki requests · 18 Mar 2025 · 1 like Where a request is for a translation or a regional version, the maintenance burden doubles and the proposal should say who carries it. If that reads as pedantic, it is,…
[2026 update] What the GIP component of tirzepatide is thought to contribute, and how… Replied, post #23 · Compounds › Tirzepatide · 9 Mar 2025 · 1 like An observation about GIP component of tirzepatide that I cannot explain and am posting anyway, on the principle that unexplained observations are more useful public…
Journal club: STEP 4 and what a withdrawal design can prove Replied, post #2 · marked as the solution · Evidence › Journal club · 19 Feb 2025 · 15 likes The opening post describes the usual case. This is about the unusual one. Having read the whole STEP 4 thread before replying: the question in the first post has not…
When a preprint is the best available evidence and we say so — a second dataset Replied, post #12 · Evidence › Preprints · 30 Jan 2025 · 1 like A preprint reporting a null result is more likely to stay a preprint, which biases the published literature and makes preprint servers more valuable rather than less.
Oxidation and deamidation mass shifts, tabulated Replied, post #40 · Analytics › Mass spectrometry · 21 Jan 2025 · 4 likes This follows post #39 rather than contradicting it. Tandem mass spectrometry: MS/MS fragments the molecular ion and uses fragment masses to confirm identity and detect…
What we do not know about retatrutide, listed explicitly Replied, post #61 · Compounds › Retatrutide · 19 Jan 2025 · 0 likes Heart rate increased in a dose-dependent way in the phase 2 work. That is not a footnote — it is one of the specific things phase 3 exists to characterise, and it is…
BPC-157: what the rodent literature actually shows, and what it does not — a second… Replied, post #6 · Compounds › Repair & healing peptides · 14 Jan 2025 · 17 likes Reported local reactions are common enough in first-hand accounts here to be worth mentioning and are not characterised in any published series. That is what the…
[2026 update] New subcategory: rationale and scope Replied, post #134 · Meta › Announcements · 9 Jan 2025 · 22 likes Taking post #132 at face value and following it one step further. Two questions I would want answered before drawing anything from the New subcategory data above: how…
HbA1c lag and what it can and cannot tell you at eight weeks Started this topic · Clinical › Bloodwork · 22 Dec 2024 · 0 likes HbA1c lag and what it can and cannot tell you at eight weeks Writing it up because I had to work it out twice and would rather nobody else did. Something about hba1c…
Second pass at: Choosing a concentration on purpose rather than by accident Replied, post #20 · Practice › Reconstitution · 20 Nov 2024 · 0 likes On Choosing a concentration, the part that usually goes wrong is that the question is asked as though it has one answer. It has a range, and the width of the range is…
What a stability-indicating method is and how you demonstrate one — one year on Replied, post #68 · Analytics › Method validation · 8 Nov 2024 · 14 likes That is the distinction I keep failing to hold on to. Written down now.
Transporting a vial for a weekend away Replied, post #26 · Practice › Storage & stability · 2 Nov 2024 · 1 like On post #22 — agreed on the reasoning, with one qualification. Vial integrity: once a vial is entered with a needle repeatedly, the rubber closure degrades and the…
Relative retention time as a better inter-laboratory comparator — does this still hold? Replied, post #15 · Analytics › Method validation · 22 Oct 2024 · 9 likes Small correction to my own earlier position on Relative retention time. I had the units the wrong way round, which changes the conclusion by an order of magnitude and…
Why I ask for the gradient before I discuss the number Replied, post #12 · Analytics › HPLC & UHPLC · 9 Aug 2024 · 28 likes Post #10 and I disagree about the size of the effect, not about the direction. A shallow gradient resolves close-eluting species that a steep one merges. Two honest…
Guidelines revision: what changed and why Replied, post #128 · Meta › Announcements · 28 Jul 2024 · 8 likes That matches what I have seen, for whatever a single anecdote is worth.
The mass-error checker and its intended scope Replied, post #155 · Data & Tools › Calculators · 26 Jul 2024 · 3 likes Where I part company with post #154, and it is a narrow parting. The calculators maintained on this site are open-source and verifiable. They are intended to check…
Second pass at: Retatrutide dose escalation in the published trials Replied, post #107 · Compounds › Retatrutide · 23 Jul 2024 · 3 likes Adding the measurement that post #106 says would settle it. The confident answers on Retatrutide dose escalation and the well-sourced answers are not the same answers,…
Spreadsheets: an appreciation Replied, post #25 · Lounge › Off topic · 9 Jun 2024 · 2 likes Mildly off-topic appreciation: whoever maintains the storage-conditions document has kept it current through three revisions without ever overstating what the…