c.falk

TL2 Moderator · Dijon

Contributes reviews on supplier material. Based in Dijon.

Joined 3 June 2025 · last posted 2d

87 posts, newest first. Showing up to 150.

Journal club: SUSTAIN 6 and its retinopathy signal Replied, post #120 · Evidence › Journal club · 26 Jul 2026 · 9 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
What consumer-accessible tests can and cannot determine — a second dataset Replied, post #125 · Analytics › Home & field testing · 26 Jul 2026 · 6 likes This follows post #122 rather than contradicting it. What physical quantity does the device measure? A colorimetric or lateral-flow method typically responds to a class…
Insurance and replacement policies, compared Replied, post #111 · Sourcing › Logistics · 23 Jul 2026 · 0 likes post #110 answers the question as asked. The question underneath it is different. Cold packs and temperature control: inclusion of cold packs at despatch is standard.…
What a certificate commits its issuer to Replied, post #63 · Analytics › COA interpretation · 19 Jul 2026 · 0 likes Endotoxin testing is separate: a certificate of purity says nothing about endotoxin. A chemically pure preparation can carry a clinically significant endotoxin load. If…
Peak-to-trough ratio at steady state for a weekly agent — the long version Replied, post #54 · Pharmacology › Pharmacokinetics · 18 Jul 2026 · 19 likes Volume of distribution: the theoretical volume the drug distributes into. For albumin-binding compounds, volume is reduced compared to drugs that do not bind protein.…
Revisiting: Protein density versus volume when you cannot eat much Replied, post #78 · Nutrition & Training › Protein & intake · 18 Jul 2026 · 22 likes Worth separating two things that post #74 runs together. Meeting protein targets on suppressed appetite: this is where the practical difficulty lies. Eating more…
What a reversed-phase purity number actually is Replied, post #53 · Analytics › HPLC & UHPLC · 14 Jul 2026 · 8 likes Reversed-phase separates on hydrophobicity. A peptide is retained on a non-polar stationary phase and eluted by increasing organic solvent. For peptides the mobile…
Pooling trials with different estimands Replied, post #77 · Evidence › Meta-analyses · 7 Jul 2026 · 0 likes Worth separating two things that post #73 runs together. Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did…
Revisiting: What pooling buys you and what it destroys Replied, post #80 · Evidence › Meta-analyses · 5 Jul 2026 · 7 likes Picking up post #77: that is the part I would want checked first. Thank you for the correction. I have edited my earlier post with a note rather than silently, so the…
Semaglutide and gastric emptying — the mechanism behind most of the side-effect profile Replied, post #89 · Compounds › Semaglutide · 3 Jul 2026 · 12 likes Gastric emptying delay is the mechanism behind most of the gastrointestinal side effects. Slowing the stomach empties it feeds less food into the intestines at a time,…
A supplier who responds to a discrepancy with silence — what changed since Replied, post #69 · Sourcing › Red flags · 24 Jun 2026 · 29 likes Coming back to post #67, because the follow-up matters more than the original answer. Rapid supplier turnover: a supplier that changes corporate structure, domain name,…
[2026 update] Regional warehouse stock versus direct despatch Replied, post #112 · Sourcing › Logistics · 24 Jun 2026 · 29 likes Cold packs and temperature control: inclusion of cold packs at despatch is standard. Whether they maintain temperature through transit depends on journey duration and…
Second pass at: Orforglipron as a non-peptide: what changes when the molecule is small Started this topic · Compounds › Oral incretins · 23 Jun 2026 · 33 likes Second pass at: Orforglipron as a non-peptide: what changes when the molecule is small Writing it up because I had to work it out twice and would rather nobody else…
Insomnia at a dose step: reported experiences — the long version Replied, post #35 · Wellbeing › Sleep · 17 Jun 2026 · 2 likes Sleep quality versus quantity: some people report changes to sleep duration; others report changes to sleep quality without duration change. Both can matter for…
Publication patterns in the BPC-157 literature, examined Replied, post #12 · Compounds › Repair & healing peptides · 12 Jun 2026 · 32 likes This follows post #9 rather than contradicting it. Oral versus injected administration claims for BPC-157: the preclinical work studied injection. Oral claims are…
A structured critique template this community uses — a second dataset Replied, post #8 · Evidence › Study critique · 11 Jun 2026 · 15 likes Criticise the method, not the author: a paper with a weak design is not a bad paper by someone with bad intentions. It is a paper that answers a limited question.…
Micronutrient adequacy at low total intake Replied, post #8 · Nutrition & Training › Protein & intake · 6 Jun 2026 · 12 likes post #7 is right about the mechanism and I think understates the practical bit. Protein supplements: whey, casein, and plant-based protein powders can help hit targets…
An 18-month record including the parts that went badly Replied, post #33 · Outcomes › Progress reports · 5 Jun 2026 · 0 likes Menstrual cycle: for people who menstruate, weight can shift by several pounds across the cycle due to fluid retention and other factors. Noting cycle phase when…
Why we ask for units every single time, with three examples of what goes wrong Replied, post #19 · Start Here › How to Ask · 5 Jun 2026 · 33 likes Coming back to post #17, because the follow-up matters more than the original answer. Two things before anyone answers the substance. First, the context in the first…
Journal club: indirect comparison between two programmes, defended and attacked Replied, post #55 · Evidence › Journal club · 13 May 2026 · 16 likes Critical appraisal template: (1) What did the trial set out to estimate? (2) Could the design answer that question? (3) Was the population sufficiently similar to your…
0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #36 · Devices › Syringes & needles · 9 May 2026 · 14 likes On post #32 — agreed on the reasoning, with one qualification. Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G) are courser. For…
The best-written scientific paper you have read Replied, post #30 · Lounge › Off topic · 4 May 2026 · 1 like Adjacent and interesting: you might post something about nutrition, bioavailability from a food perspective, or the sociology of weight. Adjacent to this community's…
Gastro-oesophageal reflux: improving or worsening? Replied, post #38 · Clinical › Comorbidities · 22 Apr 2026 · 0 likes Interactions between comorbidities: diabetes and kidney disease together change the risk calculation for hypoglycemia and for medication clearance. They are not…
Revisiting: The report format the maintainers ask for, and why each field is there Replied, post #50 · Sourcing › Vendor reports · 13 Apr 2026 · 2 likes Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that…
Spike-and-recover accuracy for a peptide assay Replied, post #75 · Analytics › Method validation · 9 Apr 2026 · 27 likes Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had…
Managing an unplanned gap in supply Replied, post #90 · Access › Shortages · 9 Apr 2026 · 0 likes Managing an unplanned gap: if a shortage causes a gap in treatment, the questions are how long the gap will be and how that affects your condition. Discussing with your…
Reading a preclinical wound-healing model and its relevance to a human tendon — a second… Replied, post #34 · Compounds › Repair & healing peptides · 11 Mar 2026 · 5 likes I read post #32 twice before replying, because I had assumed the opposite. For anyone arriving from search engines: this subcategory discusses published preclinical…
The most common factual error about semaglutide on the internet — what changed since Replied, post #45 · Compounds › Semaglutide · 9 Mar 2026 · 11 likes Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had…
Revisiting: Absolute versus relative contraindications Replied, post #40 · Safety › Contraindications · 9 Mar 2026 · 6 likes On post #36 — agreed on the reasoning, with one qualification. Diabetic retinopathy complications: a signal for this was noted in SUSTAIN 6. Current evidence is mixed.…
Air bubbles in a subcutaneous injection: the honest risk assessment — does this still… Replied, post #9 · Practice › Administration · 5 Mar 2026 · 3 likes Drawing up with one needle and injecting with another: a reasonable practice if you have extra needles. Fresh needle for injection reduces tissue drag and can decrease…
The lowest dose that does anything: is that a real question? Replied, post #26 · Practice › Dosing & titration · 3 Mar 2026 · 0 likes Splitting a weekly dose in two: the pharmacokinetic argument against is that you want the benefit of long half-life, which gives a slowly changing plasma level from a…
[2026 update] Thyroid function tests during substantial weight change Replied, post #4 · Clinical › Bloodwork · 25 Feb 2026 · 0 likes This follows post #3 rather than contradicting it. Fasting state: some lab tests require fasting; others do not. Lipids on a fasting draw differ from lipids on a fed…
Coming back to: Training through a dose escalation week Replied, post #11 · Nutrition & Training › Resistance training · 19 Jan 2026 · 2 likes Intensity: using weights that allow 6 to 12 reps before fatigue is a reasonable range for preserving muscle. Heavier weights with lower reps can work but require more…
Coming back to: Semaglutide in people without diabetes: what the evidence base looks like Replied, post #24 · Compounds › Semaglutide · 15 Jan 2026 · 5 likes Gastric emptying delay is the mechanism behind most of the gastrointestinal side effects. Slowing the stomach empties it feeds less food into the intestines at a time,…
Measurement error in home scales, with a worked standard deviation — the long version Replied, post #6 · Research Methods › Statistics · 2 Jan 2026 · 12 likes Effect sizes: the magnitude of a difference, not just whether it is statistically significant. A difference that is significant (p
Coming back to: Private prescribing in the UK: what is actually involved Replied, post #4 · Regional › UK & Ireland · 21 Dec 2025 · 2 likes Picking up post #2: that is the part I would want checked first. For anyone arriving from a search: the marked solution above is the direct answer, and the replies…
[2026 update] Whether protein timing matters at a large deficit Replied, post #5 · Nutrition & Training › Protein & intake · 15 Dec 2025 · 22 likes Protein sources: animal sources (meat, fish, eggs, dairy) are denser and easier to hit targets with. Plant sources require higher volume. Neither is nutritionally…
Follow-up: Bug report: the reconstitution calculator and a rounding edge case Replied, post #3 · Data & Tools › Calculators · 13 Dec 2025 · 1 like I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at…
Adolescents: a distinct evidence base — one year on Replied, post #42 · Clinical › Special populations · 10 Dec 2025 · 14 likes Gastroparesis: pre-existing severe delayed gastric emptying can worsen with compounds that slow it further. Discussion with a clinician is prudent if this history exists.
Dose numbers for oral formulations are not comparable to injectable ones Replied, post #7 · Compounds › Oral incretins · 28 Nov 2025 · 4 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…
Follow-up: Constipation management, with a dietitian's contribution Replied, post #21 · Practice › Side effects · 9 Nov 2025 · 2 likes Hair shedding: telogen effluvium associated with rapid weight loss is reported. The timing usually correlates with the speed of weight change rather than the compound…
Why an oral GLP-1 agonist is a formulation achievement more than a chemistry one Replied, post #25 · Compounds › Oral incretins · 31 Oct 2025 · 15 likes Dose numbers for oral formulations are not comparable to injectable ones. The 14 mg oral dose is not equivalent to any injectable dose in the traditional comparison…
Reading SURMOUNT-1 without the press release Replied, post #37 · Compounds › Tirzepatide · 18 Oct 2025 · 1 like Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Request: a diff view for wiki revisions — the long version Replied, post #45 · Meta › Feature requests · 20 Sep 2025 · 13 likes Effort estimation: some features are trivial to implement; others are substantial work. Staff will estimate effort when assessing whether a feature is feasible.
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #97 · Evidence › Study critique · 15 Sep 2025 · 0 likes This follows post #94 rather than contradicting it. Choosing the worst interpretation: "The confidence interval includes a harmful effect" is true if the CI goes from…
AOD-9604 and the fragment hypothesis, revisited Replied, post #14 · Compounds › Other compounds · 12 Sep 2025 · 0 likes post #13 is right about the mechanism and I think understates the practical bit. Thank you for the correction. I have edited my earlier post with a note rather than…
Hepatic impairment and the absence of data Replied, post #28 · Clinical › Special populations · 6 Sep 2025 · 0 likes post #27 is right about the mechanism and I think understates the practical bit. Pancreatitis history: the compounds can rarely trigger pancreatitis. A history of…
Confounding by indication, explained with a concrete example Replied, post #22 · Evidence › Study critique · 3 Sep 2025 · 2 likes Choosing the worst interpretation: "The confidence interval includes a harmful effect" is true if the CI goes from -1 to +5. But assuming the worst-case scenario is not…
When a preprint is the best available evidence and we say so Replied, post #130 · Evidence › Preprints · 2 Sep 2025 · 12 likes How to cite a preprint: author last name, first initial, et al. Title. Server name [preprint]. Posted date. Doi. Include the server name and note that it is a preprint.
Second pass at: Why this subcategory is stricter about sourcing than most Replied, post #119 · Compounds › Secretagogues & GH axis · 31 Aug 2025 · 0 likes Reading a rodent study on a secretagogue without over-extrapolating: rodent studies can show a mechanism is plausible. They cannot show magnitude of effect in humans or…
A ten-fold dose error caught before injection — one year on Replied, post #107 · Devices › Syringes & needles · 4 Aug 2025 · 25 likes On post #103 — agreed on the reasoning, with one qualification. Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what…
Substitution between formats during a shortage Replied, post #33 · Access › Shortages · 4 Aug 2025 · 6 likes Worth separating two things that post #29 runs together. Patient advocacy during shortages: some advocacy groups advocate for patients during shortages. Knowing who…
Antibiotics and a course of something with delayed emptying Replied, post #102 · Practice › Interactions · 27 Jul 2025 · 0 likes Alcohol: no absolute contraindication but it raises gastrointestinal irritation risk and this drug class already does that. The conservative position during titration…
Pooling trials with different estimands — what changed since Replied, post #6 · Evidence › Meta-analyses · 23 Jul 2025 · 1 like Picking up post #3: that is the part I would want checked first. Funnel plots: a plot of study effect size versus sample size that helps detect publication bias. If…
Specification in the result column: why that is a meaningful error Replied, post #17 · Analytics › COA interpretation · 10 Jul 2025 · 2 likes On post #13 — agreed on the reasoning, with one qualification. Water content (residual moisture) matters: lyophilised peptide is not dry. A few percent water is normal.…
Interim analyses and stopping rules — does this still hold? Replied, post #35 · Evidence › Trials · 5 Jul 2025 · 13 likes Population narrowness: most trials in this class enrolled fairly specific groups. Baseline body mass index ranges, exclusion of renal disease, exclusion of certain…
[2026 update] What we do not know about retatrutide, listed explicitly Replied, post #2 · Compounds › Retatrutide · 3 Jul 2025 · 1 like Mass and identity: a report on retatrutide should state the mass detected by LC-MS, not assume a theoretical mass. The theoretical mass is not published in…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #43 · Evidence › Trials · 20 Jun 2025 · 7 likes Surrogate endpoints: an endpoint that is not the outcome that matters but is measured as a stand-in. HbA1c is a surrogate for long-term glucose control and the…
Coming back to: Getting a referral rather than a refusal Replied, post #13 · Clinical › Prescriber conversations · 29 May 2025 · 28 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
DXA precision and the least significant change for lean mass — the long version Replied, post #105 · Outcomes › Body composition · 27 May 2025 · 10 likes I read post #103 twice before replying, because I had assumed the opposite. DXA (dual-energy X-ray absorptiometry): the standard for body composition in research.…
Pre-registering a personal experiment, seriously Replied, post #9 · Research Methods › N-of-1 designs · 26 May 2025 · 0 likes Stopping rules: decide in advance when you will stop measuring (after a defined duration, after a defined number of measurements, or after a defined condition is met).…
Airline travel with a temperature-sensitive injectable — what changed since Replied, post #30 · Devices › Cold chain · 22 May 2025 · 1 like post #29 answers the question as asked. The question underneath it is different. Temperature excursions: brief excursions above 8 °C are tolerable for most compounds.…
Splitting a vial for two laboratories: how to do it without ruining both Replied, post #31 · Sourcing › Independent verification · 2 May 2025 · 0 likes PeptideMeter: purity analysis plus structured, dated supplier verification records. Produces both individual analytical results and verification records assessed over…
[2026 update] Citation sweep results: how many references did not say what was claimed Replied, post #24 · Meta › Wiki maintenance · 22 Apr 2025 · 11 likes Picking up post #21: that is the part I would want checked first. Redundancy: if two maintained pages cover largely the same ground, consolidation might improve…
Journal club: SUSTAIN 6 and its retinopathy signal — does this still hold? Replied, post #66 · Evidence › Journal club · 1 Apr 2025 · 0 likes SURMOUNT-OSA (N Engl J Med 2024): Tirzepatide in obstructive sleep apnoea, using an objective physiological endpoint. Notable because soft endpoints are avoided. Two…
Obstructive sleep apnoea and a hard endpoint in this class Replied, post #42 · Clinical › Comorbidities · 26 Mar 2025 · 5 likes Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had…
Second pass at: Journal club: STEP 4 and what a withdrawal design can prove Replied, post #4 · Evidence › Journal club · 23 Mar 2025 · 1 like Session format: read the paper before posting. The discussion is much better when everyone has. Start with the estimand and population, then methods, then results, then…
Biased agonism: a real phenomenon, an over-used explanation Replied, post #93 · Pharmacology › Receptor biology · 14 Mar 2025 · 3 likes GLP-1 receptor signalling: the GLP-1 receptor is expressed on beta cells (insulin secretion), on neurons (appetite and gastric motility), and on myocardium…
Individual participant data versus aggregate data Replied, post #22 · Evidence › Meta-analyses · 12 Mar 2025 · 1 like Study quality and weighting: some meta-analyses weight all studies equally; others weight by study size or study quality. The choice affects the result and should be…
A promotion I argued against, and why I lost Replied, post #125 · Documentation › Doc review · 8 Mar 2025 · 0 likes New maintainer recruitment: if a page's maintainer is inactive and updates are needed, suggesting a new maintainer here can help transition responsibility.
Introducing myself and asking whether my planned first topic belongs anywhere Replied, post #14 · Start Here › Welcome · 8 Mar 2025 · 13 likes The moderation log is public. Every staff action is logged with the rule cited and the reasoning stated. If you get moderated, the explanation is there and it is worth…
Adducts: sodium, potassium, and the peak you did not expect Replied, post #28 · Analytics › Mass spectrometry · 7 Mar 2025 · 24 likes Quantitation by MS: most quantitation is done by LC-UV detection at 214 nm, not by MS, because extinction coefficients are better known. MS can quantify if an internal…
Adjudicated events and why the definition matters — the long version Replied, post #19 · Evidence › Trials · 21 Feb 2025 · 14 likes post #18 is right about the mechanism and I think understates the practical bit. Thank you for the correction. I have edited my earlier post with a note rather than…
Journal club: SURMOUNT-1, read without the press release Replied, post #57 · Evidence › Journal club · 8 Feb 2025 · 6 likes Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the…
Introducing myself and asking whether my planned first topic belongs anywhere Started this topic · Start Here › Welcome · 27 Jan 2025 · 3 likes Introducing myself and asking whether my planned first topic belongs anywhere Writing it up because I had to work it out twice and would rather nobody else did. I want…
Pancreatitis history and the risk calculus — a second dataset Replied, post #21 · Safety › Contraindications · 25 Jan 2025 · 1 like Worth separating two things that post #17 runs together. Medullary thyroid carcinoma (personal or family history) or multiple endocrine neoplasia type 2: absolute…
Follow-up: Tirzepatide's shorter half-life and its one practical consequence Replied, post #128 · Compounds › Tirzepatide · 4 Jan 2025 · 0 likes On post #124 — agreed on the reasoning, with one qualification. SURPASS-2 compared tirzepatide with semaglutide 1.0 mg, the licensed diabetes dose at that time. It did…
Fixed versus detachable needles: the trade-offs Replied, post #72 · Devices › Syringes & needles · 26 Dec 2024 · 2 likes post #71 answers the question as asked. The question underneath it is different. Sharps disposal: needles and syringes should be disposed in a sharps container (a…
When "no data" is the complete and final answer Replied, post #43 · Compounds › Other compounds · 16 Dec 2024 · 2 likes post #42 is right about the mechanism and I think understates the practical bit. How to research a compound with no human data: mechanistic plausibility is one input.…
Time to steady state after a dose increase Replied, post #118 · Pharmacology › Pharmacokinetics · 5 Nov 2024 · 30 likes I read post #116 twice before replying, because I had assumed the opposite. Having read the exchange above, I think I was wrong earlier in this topic and I want to say…
Follow-up: Recovery when intake is low: what to cut first Replied, post #6 · Nutrition & Training › Resistance training · 4 Nov 2024 · 14 likes Deload weeks: periodic weeks (every 4 to 8 weeks) with reduced volume and intensity can help with recovery and sometimes reveal strength gains that got obscured by…
Coming back to: The nausea timeline across the first four weeks, with a tabulated log Replied, post #24 · Practice › Side effects · 1 Nov 2024 · 19 likes Nausea: the most common side effect and the most dose- and titration-dependent one. It is usually most prominent in the first 24 to 48 hours after injection and…
Second pass at: Food noise reducing and the disorientation that can follow Replied, post #53 · Wellbeing › Mental health · 27 Oct 2024 · 0 likes Sleep and mental health: these compounds can affect sleep for some people. Sleep deprivation worsens mood and anxiety. Addressing sleep separately from mood matters.
Second pass at: Hoarding and why it makes a shortage worse Replied, post #68 · Access › Shortages · 11 Oct 2024 · 25 likes Managing an unplanned gap: if a shortage causes a gap in treatment, the questions are how long the gap will be and how that affects your condition. Discussing with your…
Coming back to: Purity assay versus content assay: two different numbers Replied, post #33 · Analytics › COA interpretation · 10 Aug 2024 · 20 likes This follows post #30 rather than contradicting it. Counter-ion form is crucial: peptides are isolated as salts, most often trifluoroacetate from reversed-phase…
Journal club: FLOW and the renal composite, component by component Replied, post #8 · Evidence › Journal club · 8 Jul 2024 · 14 likes SURPASS-2 (N Engl J Med 2021): Direct comparison of tirzepatide with semaglutide 1.0 mg. The 1.0 mg dose is not the highest available, which is the central and…
Assessing a warm arrival: the decision process — one year on Replied, post #2 · Sourcing › Logistics · 27 May 2024 · 10 likes the opening post is right about the mechanism and I think understates the practical bit. For anyone arriving from a search: the marked solution above is the direct…