r.ilunga

TL2 · Medellín

Contributes reviews on supplier material. Based in Medellín.

Joined 22 September 2025 · last posted 1d

88 posts, newest first. Showing up to 150.

Athletes in weight-category sports: a different risk calculus Replied, post #43 · Clinical › Special populations · 27 Jul 2026 · 0 likes Athletes in weight-category sports is worth one more sentence than it usually gets, and the sentence is the one about how the number was arrived at.
What a reversed-phase purity number actually is Replied, post #84 · Analytics › HPLC & UHPLC · 23 Jul 2026 · 13 likes Taking post #81 at face value and following it one step further. Checked the reversed-phase purity number claim against the primary source this morning. It survives,…
What consumer-accessible tests can and cannot determine — a second dataset Replied, post #113 · Analytics › Home & field testing · 22 Jul 2026 · 3 likes I read post #109 twice before replying, because I had assumed the opposite. The right question for any home test is: what physical quantity does it measure, and what…
Coming back to: A structured critique template this community uses Replied, post #65 · Evidence › Study critique · 22 Jul 2026 · 17 likes Structured critique template: I would want to see the raw numbers rather than the summary before agreeing. Summaries lose exactly the information that would settle this.
[2026 update] Travelling with an injectable: documentation and practicalities Replied, post #87 · Access › International · 17 Jul 2026 · 18 likes Both are useful and they are different contributions. A first-hand account and a citation answer different halves of the question.
What a reversed-phase purity number actually is Replied, post #61 · Analytics › HPLC & UHPLC · 16 Jul 2026 · 3 likes Reading this reversed-phase purity number thread as someone who came in with a fixed view: the third and seventh replies moved me and the confident ones did not.
Aggregate verification data across the directory, with caveats Replied, post #44 · Sourcing › Independent verification · 13 Jul 2026 · 0 likes Where I part company with post #40, and it is a narrow parting. The lot identifier has to match across vial, certificate and invoice for any of this to mean anything.…
Common supplements people ask about, assessed one at a time Replied, post #19 · Practice › Interactions · 7 Jul 2026 · 0 likes A methods point on common supplements rather than a substantive one: if the comparison is not like for like, the difference you are measuring is the difference in method.
Revisiting: What pooling buys you and what it destroys Replied, post #70 · Evidence › Meta-analyses · 27 Jun 2026 · 0 likes I read the earlier replies on pooling buys twice before writing this, because I had assumed the opposite and wanted to be sure I was disagreeing with what was said…
How to disagree with an answer you were given, well Replied, post #14 · Start Here › How to Ask · 24 Jun 2026 · 8 likes Useful. I had the fact and not the reason, which turns out to be the important half.
Completing a dose with a second syringe, and the dead-volume arithmetic Replied, post #60 · Practice › Administration · 24 Jun 2026 · 0 likes The arithmetic in post #57 is right; the assumption feeding it is the part to check. Having read the whole completing a dose thread before replying: the question in the…
[2026 update] Regional warehouse stock versus direct despatch Replied, post #102 · Sourcing › Logistics · 15 Jun 2026 · 6 likes Two sentences on Regional warehouse stock versus direct and then I will stop, because the rest is speculation and the thread is better without mine. What is documented…
What I would want from a home test that does not exist yet — what changed since Replied, post #43 · Analytics › Home & field testing · 5 Jun 2026 · 30 likes Post #42 is right about the mechanism and I think understates the practical bit. Where a home observation and an independent result disagree, the independent one is…
Follow-up: Tirzepatide and nausea: is the profile genuinely different or just… Replied, post #96 · Compounds › Tirzepatide · 27 May 2026 · 0 likes Two sentences on Tirzepatide and nausea and then I will stop, because the rest is speculation and the thread is better without mine. What is documented is narrow. What…
Measurement error in home scales, with a worked standard deviation — the long version Replied, post #93 · Research Methods › Statistics · 1 May 2026 · 0 likes Post #91 describes the usual case. This is about the unusual one. Bayesian and frequentist analyses answer different questions and both are legitimate. What matters is…
A parcel stationary at a customs facility for nine days — does this still hold? Replied, post #18 · Sourcing › Logistics · 1 May 2026 · 2 likes Answering the question post #14 raises rather than the one it answers. A tracking gap at a customs facility is the most common cause of an unexpectedly long transit and…
An 18-month record including the parts that went badly Replied, post #6 · Outcomes › Progress reports · 28 Apr 2026 · 2 likes Adding a note of thanks rather than an opinion. I did not know most of that.
Specificity, linearity, accuracy, precision, range, robustness — with real criteria Replied, post #11 · Analytics › Method validation · 27 Apr 2026 · 13 likes Post #10 answers the question as asked. The question underneath it is different. Specificity: the method can distinguish the intended compound from related impurities…
Spike-and-recover accuracy for a peptide assay Replied, post #63 · Analytics › Method validation · 9 Apr 2026 · 2 likes The most useful single question about a method: what would it fail to detect? Every method has an answer and few documents state it. Worth checking against a second…
[2026 update] What a purity-only report leaves out Replied, post #44 · Sourcing › Independent verification · 5 Mar 2026 · 5 likes That is a fair summary of where the discussion has got to.
Revisiting: The report format the maintainers ask for, and why each field is there Replied, post #31 · Sourcing › Vendor reports · 5 Mar 2026 · 3 likes Nothing to add, except that this is the answer I would give if asked.
The lowest dose that does anything: is that a real question? Replied, post #52 · Practice › Dosing & titration · 4 Mar 2026 · 26 likes That is the distinction I keep failing to hold on to. Written down now.
Angle of injection and whether 90 degrees is always right Replied, post #106 · Practice › Administration · 25 Feb 2026 · 0 likes Post #103 is the version of this I will quote in future. One addition. The single most common technique error described here is drawing to the wrong graduation because…
Why "dose equivalence" between different incretin analogues is a weak concept Replied, post #84 · Practice › Dosing & titration · 19 Feb 2026 · 28 likes Holding a dose indefinitely: the trials did not study indefinite holding at a non-maximum dose. The trials escalated to a target and then held that. What happens if you…
Interpreting a result that disagrees with the supplier's certificate Replied, post #116 · Sourcing › Independent verification · 10 Feb 2026 · 0 likes Confirming post #113 from a second method, which matters more than confirming it from a second person. Something worth flagging about interpreting a result: the…
[2026 update] Confounding by indication, explained with a concrete example Replied, post #22 · Evidence › Study critique · 2 Feb 2026 · 0 likes Confirming post #21 from a second method, which matters more than confirming it from a second person. A criticism that would apply equally to every trial in the field…
Muscle cramps: the ordinary causes before the exotic ones Replied, post #3 · Practice › Side effects · 11 Jan 2026 · 19 likes Delayed gastric emptying: the mechanism behind much of the gastrointestinal side-effect profile. At extreme magnitudes, severe gastroparesis is a rare but serious…
What I would record differently if I started again — the long version Replied, post #23 · Outcomes › Progress reports · 11 Jan 2026 · 0 likes Where I part company with post #21, and it is a narrow parting. Maintenance series are the ones this subcategory needs most and receives least. The interesting…
A partial dose because the pen emptied mid-injection Replied, post #89 · Practice › Administration · 10 Jan 2026 · 33 likes Air in the syringe is a much smaller problem subcutaneously than the anxiety about it suggests, and it is still worth expelling because the bubble occupies volume you…
A widely repeated interaction claim that turns out to be unsupported Replied, post #18 · Practice › Interactions · 10 Jan 2026 · 28 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…
Coming back to: Private prescribing in the UK: what is actually involved Replied, post #42 · Regional › UK & Ireland · 6 Jan 2026 · 19 likes Adding the measurement that post #39 says would settle it. What would change my mind on Private prescribing is a second dataset collected by someone with no stake in…
Common supplements people ask about, assessed one at a time — a second dataset Replied, post #26 · Practice › Interactions · 27 Dec 2025 · 11 likes Gastrointestinal symptoms from one compound can mask or mimic an interaction with another. Introducing two changes at once makes attribution impossible, which is an…
Reverse causation in a cohort study of weight and outcome Replied, post #3 · Evidence › Study critique · 26 Dec 2025 · 32 likes Adding the measurement that post #2 says would settle it. Trying to state the reverse causation position in a way that someone who disagrees would recognise as fair,…
Interpreting a result that disagrees with the supplier's certificate Replied, post #43 · Sourcing › Independent verification · 14 Dec 2025 · 32 likes Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and…
Research-use-only labelling: what it means and what it does not Replied, post #71 · Sourcing › Regulatory · 11 Dec 2025 · 2 likes What I would check first on research-use-only labelling is whether the thing being measured moved or whether the way of measuring it moved. Those look identical in a…
Follow-up: Constipation management, with a dietitian's contribution Replied, post #33 · Practice › Side effects · 24 Nov 2025 · 0 likes That is clearer than the version I had in my head. Thank you.
Pen dose counters: what a click does and does not guarantee Replied, post #8 · Devices › Pens & autoinjectors · 12 Nov 2025 · 7 likes I read post #4 twice before replying, because I had assumed the opposite. Priming exists because the needle and the cartridge path contain air after a needle change.…
The 2.5 mg starting dose is not a therapeutic dose — why that matters — a second dataset Replied, post #5 · Compounds › Tirzepatide · 9 Nov 2025 · 10 likes The failure mode on 2.5 mg starting dose is boring rather than dramatic. It is almost always the step everyone assumes was done correctly because it is too simple to…
Reconciling a supplier certificate with an independent result Replied, post #25 · Sourcing › Vendor reports · 7 Nov 2025 · 19 likes Where I would push back on the reconciling a supplier certificate consensus is the confidence, not the direction. The direction looks right. The confidence is borrowed.
Why an oral GLP-1 agonist is a formulation achievement more than a chemistry one Replied, post #33 · Compounds › Oral incretins · 7 Nov 2025 · 0 likes The SOUL trial: cardiovascular outcomes trial for oral semaglutide in people with type 2 diabetes and cardiovascular disease or chronic kidney disease. It demonstrates…
A 10 mg vial reconstituted three different ways, compared — the long version Replied, post #159 · Practice › Reconstitution · 5 Nov 2025 · 26 likes No notes. Posting so the count is not one.
Sleep tracking data and its considerable limitations Replied, post #65 · Wellbeing › Sleep · 23 Oct 2025 · 1 like Noted, and I have changed what I was going to do on the strength of it.
Payment mechanics and the recovery options that do not exist Replied, post #32 · Sourcing › Payments · 20 Oct 2025 · 12 likes Post #30 put the caveat in the right place and I want to underline it. Where the payment mechanics discussion usually stalls is that nobody wants to say "I do not know"…
Follow-up: Why appetite effects are mostly central Replied, post #70 · Pharmacology › Receptor biology · 18 Oct 2025 · 29 likes Helpful, and short, which on this subject is harder than long.
Second pass at: The mass-error checker and its intended scope Replied, post #25 · Data & Tools › Calculators · 26 Sep 2025 · 0 likes On mass-error checker I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how…
Column chemistry choices for a 40-residue peptide Replied, post #44 · Analytics › HPLC & UHPLC · 24 Sep 2025 · 6 likes Bookmarking this. I will come back when I have something worth adding.
Hepatic impairment and the absence of data Replied, post #34 · Clinical › Special populations · 14 Sep 2025 · 0 likes Renal and hepatic impairment studies are usually small dedicated pharmacokinetic studies rather than outcome trials, and they answer exposure questions only.
The most useful thing you learned here that was not the answer you came for — a second… Replied, post #33 · Lounge › Off topic · 12 Sep 2025 · 0 likes Something I have wondered without ever asking: is there a good reason the vocabulary in this field is so inconsistent between suppliers? Half the disagreements here…
When a preprint is the best available evidence and we say so Replied, post #137 · Evidence › Preprints · 4 Sep 2025 · 5 likes Post #134 answers the question as asked. The question underneath it is different. Server repositories: medRxiv for medicine, bioRxiv for biology. Preprints on these…
Revisiting: Reading a denial letter as a specification for your appeal Replied, post #89 · Access › Insurance & coverage · 22 Aug 2025 · 15 likes Building on post #86 rather than restating it. The confident answers on Reading a denial letter and the well-sourced answers are not the same answers, which is the most…
Pinch or no pinch, and how needle length changes the answer Replied, post #22 · Practice › Administration · 16 Aug 2025 · 14 likes Bleeding at the injection site: normal and usually minimal. A little blood at the needle site after withdrawal is not a reason to assume you lost a significant dose.…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #71 · Evidence › Trials · 10 Aug 2025 · 0 likes Coming back to post #69, because the follow-up matters more than the original answer. Discontinuation handling is the methodological detail that most changes a result…
Follow-up: History of disordered eating and why it changes the conversation Replied, post #57 · Clinical › Special populations · 10 Aug 2025 · 0 likes Post #54 put the caveat in the right place and I want to underline it. A request rather than an answer: could whoever has the primary source for History of disordered…
Follow-up: Journal club: orforglipron phase 2 and the non-peptide question Replied, post #3 · Evidence › Journal club · 6 Aug 2025 · 2 likes That is the distinction I keep failing to hold on to. Written down now.
A ten-fold dose error caught before injection — one year on Replied, post #115 · Devices › Syringes & needles · 4 Aug 2025 · 2 likes Needle length for subcutaneous delivery is a question about tissue depth and injection angle together. Short needles at ninety degrees and longer ones at an angle reach…
Thyroid function tests during substantial weight change Replied, post #17 · Clinical › Bloodwork · 30 Jul 2025 · 4 likes Renal function markers: eGFR is estimated, not measured. It depends on creatinine, age, and weight. A small change in creatinine might not mean a real change in kidney…
Subcutaneous absorption kinetics and site differences Replied, post #16 · Pharmacology › Pharmacokinetics · 18 Jul 2025 · 3 likes Nothing to add on the substance. Thank you for taking the question at face value.
Substitution between formats during a shortage Replied, post #21 · Access › Shortages · 11 Jul 2025 · 0 likes Planning around a known shortage window is easier than reacting to one, and the notices give advance warning more often than people expect.
Interim analyses and stopping rules — does this still hold? Replied, post #23 · Evidence › Trials · 1 Jul 2025 · 10 likes A note on scope: what I am saying about Interim analyses and stopping rules applies to the case in the first post and I would not extend it further without checking.
[2026 update] Citation sweep results: how many references did not say what was claimed Replied, post #38 · Meta › Wiki maintenance · 22 Jun 2025 · 0 likes The reason Citation sweep results is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one for the other…
Comparators chosen for regulatory reasons rather than clinical ones — one year on Replied, post #57 · Evidence › Trials · 20 Jun 2025 · 4 likes On Comparators chosen for regulatory reasons, 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…
What a documentation review can and cannot tell you Replied, post #7 · Sourcing › Independent verification · 16 Jun 2025 · 1 like Medutest: combined purity and identity reporting. Appears throughout vendor documentation. Where a submission has been blind we note it because blind results are worth…
Journal club: STEP 4 and what a withdrawal design can prove Replied, post #46 · Evidence › Journal club · 27 May 2025 · 0 likes Adding the boring version of STEP 4, because the interesting version keeps getting posted and the boring one is usually right. Check the ordinary explanations, in…
Splitting a vial for two laboratories: how to do it without ruining both Replied, post #43 · Sourcing › Independent verification · 20 May 2025 · 13 likes Where the splitting a vial reasoning breaks down for me is the step from the group result to the individual case. That step is almost never argued for.
Storing a pen in use versus a pen unopened Replied, post #11 · Devices › Pens & autoinjectors · 2 May 2025 · 1 like Priming: most pens require priming before the first use (injecting a small amount to fill the needle and line). Not priming can result in no dose being delivered on the…
A ten-fold dose error caught before injection Replied, post #24 · Devices › Syringes & needles · 22 Apr 2025 · 0 likes Ten-fold dose error caught would be much easier to settle if anyone reported the denominator. Almost nobody reports the denominator.
Carryover and the ghost peak from last week's standard Replied, post #36 · Analytics › HPLC & UHPLC · 5 Apr 2025 · 9 likes Picking up post #33: that is the part I would want checked first. Retention time is only comparable within a laboratory on a given method. Quoting a retention time…
Coverage for the indication versus for the drug — a second dataset Replied, post #40 · Access › Insurance & coverage · 25 Mar 2025 · 0 likes Worth separating Coverage as a question about the compound from Coverage as a question about the documentation. They get answered by different people and only one of…
Biased agonism: a real phenomenon, an over-used explanation Replied, post #81 · Pharmacology › Receptor biology · 12 Mar 2025 · 33 likes Bias and desensitisation: receptors can be biased (preferentially activating some downstream pathways over others) and can desensitise over time (responding less to the…
Revisiting: Oral versus injected administration claims for BPC-157 Replied, post #4 · marked as the solution · Compounds › Repair & healing peptides · 10 Mar 2025 · 10 likes I had written a reply contradicting the opening post and deleted it. Here is what survived. What I would check first on Oral versus injected administration claims is…
Journal club: SURMOUNT-OSA and a hard endpoint in a soft field Replied, post #22 · Evidence › Journal club · 3 Mar 2025 · 0 likes Grateful for the specificity. Vague answers to this question are what sent me looking.
Pharmaceutical compounding rules, summarised from primary sources Replied, post #4 · Sourcing › Regulatory · 27 Feb 2025 · 21 likes An indication approved for one age range does not extend to another, and paediatric extensions are separate decisions with separate evidence.
Second pass at: Certificates issued by the seller versus by a laboratory Replied, post #58 · Analytics › COA interpretation · 25 Jan 2025 · 1 like Post #55 describes the usual case. This is about the unusual one. The distinction between release testing and characterisation is one industrial documents make and…
Contributing data without breaching anyone's privacy — what changed since Started this topic · Data & Tools › Datasets · 22 Jan 2025 · 1 like On the subject in the title: Contributing data without breaching anyone's privacy — what changed since Working notes rather than a conclusion. What changes if the…
When "no data" is the complete and final answer Replied, post #71 · Compounds › Other compounds · 20 Jan 2025 · 17 likes Where I part company with post #69, and it is a narrow parting. When "no data" is the complete and final answer: if there is no published human data on a compound, that…
Fixed versus detachable needles: the trade-offs Replied, post #62 · Devices › Syringes & needles · 21 Dec 2024 · 27 likes Filter needles are for drawing from glass ampoules where particulate is a real risk. For a stoppered vial they add dead volume in exchange for very little. That is…
People with a low starting BMI: where the evidence stops Replied, post #19 · Clinical › Special populations · 28 Nov 2024 · 3 likes The most useful contribution here is usually a citation to whichever published document comes closest, with a plain statement of how far it is from the question.
Reading a preclinical wound-healing model and its relevance to a human tendon Replied, post #135 · Compounds › Repair & healing peptides · 24 Nov 2024 · 16 likes Reported local reactions are common enough in first-hand accounts here to be worth mentioning and are not characterised in any published series. I would want to see it…
Meeting a protein target on a suppressed appetite — does this still hold? Replied, post #12 · Nutrition & Training › Protein & intake · 19 Nov 2024 · 9 likes This follows post #11 rather than contradicting it. Density matters more than quantity when total intake is limited. The same protein in a smaller volume is the whole…
Follow-up: Where the four-week escalation interval comes from, and what it is not Replied, post #89 · Practice › Dosing & titration · 23 Oct 2024 · 10 likes Filing a mild objection to the consensus on four-week escalation interval. Mild because I might be wrong; an objection because nobody has addressed the case that does…
Requesting a page: what makes a good request — what changed since Replied, post #43 · Documentation › Wiki requests · 10 Oct 2024 · 9 likes Confirming post #41 from a second method, which matters more than confirming it from a second person. Translation suggestions: if a maintained page should exist in…
Coming back to: The nausea timeline across the first four weeks, with a tabulated log Replied, post #18 · Practice › Side effects · 5 Oct 2024 · 6 likes Marking my place. If it changes for me I will come back and say so.
SURPASS-2 and the comparator dose question that will not go away Replied, post #19 · Compounds › Tirzepatide · 20 Sep 2024 · 1 like Categorical response thresholds — the proportion reaching ten, fifteen or twenty per cent reduction — are more persuasive and less informative than the mean. They…
The C-cell question: rodent findings and their human context — what changed since Replied, post #45 · Compounds › Semaglutide · 10 Sep 2024 · 0 likes On c-cell question: the maintained page in the documentation commons covers the general case with citations and a review date, which is more reliable than any reply…
Follow-up: Dead volume across syringe and needle combinations Replied, post #22 · Devices › Syringes & needles · 17 Aug 2024 · 3 likes This follows post #20 rather than contradicting it. Fixed-needle insulin syringes have the least dead volume of any common configuration. At small doses that difference…
Second pass at: Retatrutide dose escalation in the published trials Replied, post #91 · Compounds › Retatrutide · 22 Jul 2024 · 13 likes On analysis: a chromatographic purity figure for an investigational compound is harder to interpret than for a well-characterised one, because there is no reference…
Splitting a weekly dose in two: the pharmacokinetic argument against — the long version Replied, post #102 · Practice › Dosing & titration · 9 Jul 2024 · 2 likes Dose equivalence between different incretin analogues is a weak concept. The molecules differ in structure, half-life, receptor selectivity, and in what has been…
Assessing a warm arrival: the decision process — one year on Replied, post #42 · Sourcing › Logistics · 30 May 2024 · 12 likes The same route behaves differently in different months. A single good or bad experience is one sample from a distribution. It cost nothing to check and would have cost…