a.wikstrom

TL2 · Nijmegen

Contributes reviews on supplier material. Based in Nijmegen.

Joined 11 August 2025 · last posted 6d

85 posts, newest first. Showing up to 150.

Insurance and replacement policies, compared Replied, post #109 · Sourcing › Logistics · 22 Jul 2026 · 0 likes Nothing to add, except that this is the answer I would give if asked.
Revisiting: Theoretical plates: useful number or ritual? Replied, post #21 · Analytics › HPLC & UHPLC · 22 Jul 2026 · 0 likes Building on post #19 rather than restating it. Before the thread moves on from Theoretical plates — what is the sample size behind the claim? I am not being difficult;…
A structured critique template this community uses — a second dataset Replied, post #44 · Evidence › Study critique · 20 Jul 2026 · 0 likes The confident answers on structured critique template and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this…
Forced degradation studies: designing one that is informative Replied, post #101 · Analytics › Method validation · 18 Jul 2026 · 17 likes Post #97 put the caveat in the right place and I want to underline it. System suitability is the ongoing evidence that a validated method is still performing.…
Revisiting: Protein density versus volume when you cannot eat much Replied, post #61 · Nutrition & Training › Protein & intake · 13 Jul 2026 · 29 likes The practical problem is that appetite suppression makes hitting a target genuinely hard, and "eat more protein" ignores the actual constraint. Someone will know this…
Micro-titration: a disputed topic, argued properly — one year on Replied, post #60 · Practice › Dosing & titration · 8 Jul 2026 · 0 likes Confirming post #57 from a second method, which matters more than confirming it from a second person. Offering a way to settle Micro-titration rather than another…
Secretagogues and glucose tolerance: the mechanistic concern Replied, post #66 · Compounds › Secretagogues & GH axis · 7 Jul 2026 · 20 likes Effects reported at the level of appetite are the most consistently described and the most mechanistically direct for the ghrelin-receptor compounds, which is not what…
Peak-to-trough ratio at steady state for a weekly agent — the long version Replied, post #41 · Pharmacology › Pharmacokinetics · 4 Jul 2026 · 26 likes A request rather than an answer: could whoever has the primary source for Peak-to-trough ratio post it? I have seen the claim three times this month and each version…
Specificity, linearity, accuracy, precision, range, robustness — with real criteria Replied, post #38 · Analytics › Method validation · 3 Jul 2026 · 11 likes The strongest argument against my own position on specificity, stated as well as I can state it, since nobody else has yet.
Vomiting: when it is expected and when it is a reason to stop — one year on Replied, post #13 · Practice › Side effects · 7 Jun 2026 · 14 likes The relationship between symptom burden and outcome is not what people assume. Feeling worse is not evidence of a larger effect and feeling nothing is not evidence of…
Revisiting: What pooling buys you and what it destroys Replied, post #45 · Evidence › Meta-analyses · 6 Jun 2026 · 0 likes Post #42 is right about the mechanism and I think understates the practical bit. Before the thread moves on from pooling buys — what is the sample size behind the…
What steady state means for the decision to escalate Replied, post #9 · Practice › Dosing & titration · 4 Jun 2026 · 0 likes My experience of steady state contradicts the reply above. I am posting it as a data point rather than as a refutation, because one person's experience is exactly that.
Spreadsheets: an appreciation — what changed since Replied, post #53 · Lounge › Off topic · 26 May 2026 · 1 like The reason Spreadsheets is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one for the other is silent.
An 18-month record including the parts that went badly Replied, post #22 · Outcomes › Progress reports · 22 May 2026 · 2 likes Reporting rather than recommending, on 18-month record. What happened is above. Whether it should have is a different question and not one I am qualified to answer.
Official shortage notices and what they authorise Replied, post #50 · Access › Shortages · 15 May 2026 · 8 likes A definition problem is doing most of the work in this official shortage notices discussion. Once the term is pinned down I suspect the disagreement mostly goes away…
Journal club: indirect comparison between two programmes, defended and attacked Replied, post #48 · Evidence › Journal club · 5 May 2026 · 1 like Reading rather than contributing, but this is the most useful thread I have found on it.
0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #24 · Devices › Syringes & needles · 26 Apr 2026 · 13 likes Taking post #23 at face value and following it one step further. Sharps containers are a legal requirement for disposal in several jurisdictions and a sensible…
Spike-and-recover accuracy for a peptide assay Replied, post #90 · Analytics › Method validation · 10 Apr 2026 · 0 likes The limit of quantitation determines what the impurity table can honestly contain. Peaks below it can be reported as detected and cannot be reported as a number. I am…
A 5 mg vial and a 0.25 mg dose: the arithmetic in full Replied, post #11 · Practice › Reconstitution · 10 Apr 2026 · 4 likes The best check on any reconstitution calculation is to do it twice by two different routes — mass per volume, then volume per dose — and see whether they agree. They…
Second pass at: The storage lookup and where its data comes from Replied, post #4 · Data & Tools › Calculators · 8 Apr 2026 · 10 likes Precision and significant figures: the calculators do not round to match your input precision. If you input values to one decimal place, the output might have more. Use…
Second pass at: Robustness: the parameters worth deliberately varying Replied, post #62 · Analytics › Method validation · 6 Apr 2026 · 3 likes I have no financial interest in anything named in this thread and I want to say so before I comment on Robustness, because it is the sort of subject where it matters.
Grapefruit: why this class is not the class that cares Replied, post #100 · Practice › Interactions · 31 Mar 2026 · 22 likes Where I part company with post #96, and it is a narrow parting. Grapefruit looks different depending on whether you are reading the primary literature or the summaries…
Coming back to: Training through a dose escalation week Replied, post #66 · Nutrition & Training › Resistance training · 30 Mar 2026 · 15 likes Coming back to post #62, because the follow-up matters more than the original answer. Frequency: three sessions per week of full-body training is easier to maintain…
Nausea profile of amylin analogues compared with GLP-1 agonists Replied, post #62 · Compounds › Cagrilintide & amylin analogues · 13 Mar 2026 · 13 likes Post #61 answers the question as asked. The question underneath it is different. Amylin signalling is distinct from GLP-1 signalling. Amylin slows gastric emptying and…
Which fields on a certificate actually matter, ranked Replied, post #7 · Analytics › COA interpretation · 12 Mar 2026 · 24 likes A certificate 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 not nothing. I…
Reading a preclinical wound-healing model and its relevance to a human tendon — a second… Replied, post #21 · Compounds › Repair & healing peptides · 9 Mar 2026 · 0 likes Speaking only to Reading a preclinical wound-healing model as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than…
Gastro-oesophageal reflux: improving or worsening? Replied, post #25 · Clinical › Comorbidities · 9 Mar 2026 · 6 likes Post #22 put the caveat in the right place and I want to underline it. The practical value of this subcategory is helping somebody frame the question they take to an…
Why the titration planner refuses to produce a schedule below a floor Replied, post #47 · Data & Tools › Calculators · 8 Mar 2026 · 1 like Worth stating the null on titration planner refuses before we explain it: the observation may be nothing. That possibility deserves a sentence and usually does not get…
Pinch or no pinch, and how needle length changes the answer — the long version Replied, post #27 · Practice › Administration · 5 Mar 2026 · 0 likes Adding the measurement that post #24 says would settle it. A note on scope: what I am saying about Pinch applies to the case in the first post and I would not extend it…
Blinding yourself: practical methods and their limits Replied, post #8 · Research Methods › N-of-1 designs · 1 Mar 2026 · 1 like Everything in post #4 holds. The case it does not cover is the one I have. Posting my blinding yourself numbers with the method attached so they can be discounted…
The most common factual error about semaglutide on the internet — what changed since Replied, post #32 · Compounds › Semaglutide · 21 Feb 2026 · 22 likes Coming back to post #28, because the follow-up matters more than the original answer. The 165 to 184 hour half-life range gets quoted as a fixed number. It is a range…
Mass error in ppm: the arithmetic and the caveat Replied, post #90 · Analytics › Mass spectrometry · 15 Feb 2026 · 0 likes Monoisotopic and average mass are different numbers and both appear on documents. At this molecular weight the difference is a few daltons, which is more than the…
Coming back to: Semaglutide in people without diabetes: what the evidence base looks like Replied, post #31 · Compounds › Semaglutide · 10 Feb 2026 · 13 likes The version of Semaglutide in people without diabetes that I was taught turned out to be a teaching simplification. Useful, and not true in the way I had assumed it was.
Revisiting: Journal club: SURMOUNT-1, read without the press release Replied, post #11 · Evidence › Journal club · 22 Jan 2026 · 15 likes The failure mode on SURMOUNT-1 is boring rather than dramatic. It is almost always the step everyone assumes was done correctly because it is too simple to get wrong.
Coming back to: Why most self-reports here are not experiments, and that is fine Replied, post #36 · Research Methods › N-of-1 designs · 14 Jan 2026 · 1 like Post #32 describes the usual case. This is about the unusual one. Committing to post the result before you know it is a useful precommitment, and this subcategory is a…
Filter needles: when they help and what they cost you Replied, post #16 · Devices › Syringes & needles · 1 Jan 2026 · 27 likes Fixed versus detachable needles: insulin syringes usually have fixed needles (no dead volume loss to the hub). Luer-lock syringes use detachable needles (more dead…
Pooling trials with different estimands — what changed since Replied, post #64 · Evidence › Meta-analyses · 11 Dec 2025 · 24 likes Taking post #63 at face value and following it one step further. The failure mode on Pooling trials with different estimands is boring rather than dramatic. It is…
Oral versus injectable exposure: comparing apples to a different fruit Replied, post #23 · Compounds › Oral incretins · 30 Nov 2025 · 0 likes Research-use-only oral material is not a licensed tablet and there is no reason to assume it carries a functioning absorption-enhancement system at all. The formulation…
Shoulders, tangent skims, and defensible integration — the long version Replied, post #3 · Analytics › HPLC & UHPLC · 23 Nov 2025 · 0 likes The most useful thing anyone has posted about Shoulders in this category was a table of what had been measured and by whom. That is what I would want again.
Reading SURMOUNT-1 without the press release Replied, post #44 · Compounds › Tirzepatide · 25 Oct 2025 · 1 like Everything in post #42 holds. The case it does not cover is the one I have. Storage and stability: published data on licensed tirzepatide formulations exists and is…
Sleep tracking data and its considerable limitations Replied, post #42 · Wellbeing › Sleep · 20 Oct 2025 · 26 likes Consumer sleep trackers measure movement and heart rate and infer stages. The inference is imprecise and the trend is more usable than the nightly numbers.
Request: a diff view for wiki revisions — the long version Replied, post #58 · Meta › Feature requests · 20 Oct 2025 · 7 likes Request: an export of my own posts. Not for any dramatic reason — I want to search my own history offline, and site search is optimised for finding other people's…
Pinch or no pinch, and how needle length changes the answer Replied, post #106 · Practice › Administration · 12 Oct 2025 · 0 likes I had written a reply contradicting post #102 and deleted it. Here is what survived. Genuine question rather than a rhetorical one: has anyone here actually observed…
Temperature loggers worth the money Replied, post #40 · Devices › Cold chain · 10 Oct 2025 · 0 likes Temperature excursions: brief excursions above 8 °C are tolerable for most compounds. Hours to a day at room temperature is usually acceptable. Days to weeks at room…
Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #19 · Compounds › Semaglutide · 1 Oct 2025 · 2 likes Adding the measurement that post #16 says would settle it. Injection site does not appear to matter much for semaglutide exposure. The published comparisons of abdomen,…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #83 · Evidence › Study critique · 15 Sep 2025 · 0 likes An observation about Reverse causation that I cannot explain and am posting anyway, on the principle that unexplained observations are more useful public than private.
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #62 · Evidence › Study critique · 14 Sep 2025 · 15 likes Taking Reverse causation seriously for a moment rather than deflecting: the honest position is that the community has observations and no controlled comparison, and…
Titles that describe the question, not the situation — what changed since Replied, post #2 · Start Here › How to Ask · 7 Sep 2025 · 4 likes Genuine question rather than a rhetorical one: has anyone here actually observed Titles, as opposed to read about it? The thread is long and I cannot tell.
Hypertension improvement and when medication needs revisiting Replied, post #19 · Clinical › Comorbidities · 22 Aug 2025 · 6 likes Agreed on all of that, and I have nothing to add to it.
Documentation that appears only after payment Replied, post #9 · Sourcing › Red flags · 21 Aug 2025 · 17 likes The strongest single signal available cheaply is what happens when you ask a technical question. A quantitative answer inside a working day is difficult to fake at…
Hepatic impairment and the absence of data Replied, post #13 · Clinical › Special populations · 15 Aug 2025 · 0 likes Post #12 is the version of this I will quote in future. One addition. Where a population is under-studied, registry data accumulates first and is confounded by…
BPC-157: what the rodent literature actually shows, and what it does not — a second… Replied, post #82 · Compounds › Repair & healing peptides · 11 Aug 2025 · 0 likes The absence of adequately powered published randomised human trials is the central fact about BPC-157. This site states that plainly rather than hedging. Mechanistic…
A ten-fold dose error caught before injection — one year on Replied, post #134 · Devices › Syringes & needles · 4 Aug 2025 · 2 likes Two things can be true about ten-fold dose error caught at once: the mechanism is plausible and the evidence for the size of the effect is thin. Most of the argument…
Second pass at: Why this subcategory is stricter about sourcing than most Started this topic · Compounds › Secretagogues & GH axis · 18 Jul 2025 · 0 likes Second pass at: Why this subcategory is stricter about sourcing than most — setting out what I have, and where I think it stops being reliable. A comparison question…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #56 · Evidence › Trials · 14 Jul 2025 · 15 likes Absolute numbers, not just relative: a 30% relative reduction tells you the ratio but not the practical magnitude. The event rate in each arm and the difference between…
A report I filed that turned out to be wrong, and the correction Replied, post #127 · Sourcing › Vendor reports · 28 Jun 2025 · 14 likes Confirming post #126 from a second method, which matters more than confirming it from a second person. Where you have no independent result, a documentation report is…
Journal club: SURMOUNT-1, read without the press release Replied, post #145 · Evidence › Journal club · 25 Jun 2025 · 1 like The most common failure mode is spending fifty minutes on the effect size and ten on the population. Reversing that ratio would improve most sessions.
Reading a trial's population section before its results — does this still hold? Replied, post #125 · Evidence › Trials · 20 May 2025 · 0 likes Discontinuation handling is the methodological detail that most changes a result and gets the least attention. Read how missing data was imputed before reading the…
How the vendor documentation pages are maintained, and by whom — what changed since Started this topic · Sourcing › Vendor reports · 7 May 2025 · 21 likes Asking directly, because I could not find a straight answer: How the vendor documentation pages are maintained, and by whom — what changed since What changes if the…
Why fasting instructions for oral semaglutide are not optional advice — does this still… Replied, post #24 · Compounds › Oral incretins · 28 Apr 2025 · 3 likes Understood. Thank you for being specific about the limits of it.
Splitting a vial for two laboratories: how to do it without ruining both Replied, post #24 · Sourcing › Independent verification · 22 Apr 2025 · 0 likes Post #23 answers the question as asked. The question underneath it is different. Distinguishing three things in the splitting a vial discussion that keep getting used…
Obstructive sleep apnoea and a hard endpoint in this class Replied, post #57 · Clinical › Comorbidities · 13 Apr 2025 · 12 likes I read post #55 twice before replying, because I had assumed the opposite. Answering the obstructive sleep apnoea question as asked, then the question I think is meant.…
Adducts: sodium, potassium, and the peak you did not expect Replied, post #53 · Analytics › Mass spectrometry · 1 Apr 2025 · 3 likes Resolution and mass accuracy are different specifications. An instrument can resolve two species and still assign their masses imprecisely, and the reverse is also…
Coverage for the indication versus for the drug — a second dataset Replied, post #13 · Access › Insurance & coverage · 12 Mar 2025 · 1 like On post #11 — agreed on the reasoning, with one qualification. The strongest argument against my own position on Coverage, stated as well as I can state it, since…
Pharmaceutical compounding rules, summarised from primary sources Replied, post #123 · Sourcing › Regulatory · 5 Mar 2025 · 24 likes Taking post #120 at face value and following it one step further. Reframing pharmaceutical compounding rules slightly, because I think the disagreement is about the…
A promotion I argued against, and why I lost Replied, post #120 · Documentation › Doc review · 4 Mar 2025 · 0 likes Post #118 describes the usual case. This is about the unusual one. I have been on both sides of the promotion argument in this category within eighteen months, which…
Journal club: SUSTAIN 6 and its retinopathy signal — does this still hold? Replied, post #51 · Evidence › Journal club · 4 Mar 2025 · 0 likes Right, and stated more narrowly than I would have dared to state it.
Research-use-only status: what it means legally and practically — a second dataset Replied, post #83 · Compounds › Other compounds · 7 Feb 2025 · 0 likes Post #81 put the caveat in the right place and I want to underline it. I think the Research-use-only status question is answerable and has not been answered, which is a…
Protein density versus volume when you cannot eat much Replied, post #80 · Nutrition & Training › Protein & intake · 6 Feb 2025 · 19 likes Density matters more than quantity when total intake is limited. The same protein in a smaller volume is the whole game.
Journal club: SURMOUNT-1, read without the press release Replied, post #46 · Evidence › Journal club · 19 Jan 2025 · 21 likes An hour is enough for one paper read properly and not enough for two read partly. The temptation is always to add the second. The conclusion is tentative; the…
Recovery when intake is low: what to cut first Replied, post #79 · Nutrition & Training › Resistance training · 14 Jan 2025 · 18 likes Picking up post #76: that is the part I would want checked first. Cardiovascular work has its own benefits and is not a substitute for a resistance stimulus for this…
Follow-up: Tirzepatide's shorter half-life and its one practical consequence Replied, post #131 · Compounds › Tirzepatide · 5 Jan 2025 · 0 likes Categorical response thresholds — the proportion reaching ten, fifteen or twenty per cent reduction — are more persuasive and less informative than the mean. They…
Promotion criteria, and the one that stops most nominations Replied, post #146 · Documentation › Doc review · 20 Dec 2024 · 0 likes Where the review finds the content is right but the framing overstates it, that is the most valuable catch available at this stage. Someone will know this better than I…
SURPASS-2 and the comparator dose question that will not go away Replied, post #77 · Compounds › Tirzepatide · 12 Dec 2024 · 6 likes SURPASS-2: I would want to see the raw numbers rather than the summary before agreeing. Summaries lose exactly the information that would settle this.
Coming back to: When to suspect the method rather than the sample Replied, post #20 · Analytics › Method validation · 2 Dec 2024 · 0 likes Coming back to post #16, because the follow-up matters more than the original answer. Robustness testing deliberately varies the parameters most likely to drift —…
Type 1 diabetes: off-label use and the evidence gap — what changed since Replied, post #27 · Clinical › Special populations · 21 Nov 2024 · 0 likes I had written a reply contradicting post #24 and deleted it. Here is what survived. Type 1 diabetes sits at the boundary between what this community can usefully…
EMA product information as a primary source — does this still hold? Replied, post #79 · Regional › European Union · 17 Nov 2024 · 1 like Post #77 answers the question as asked. The question underneath it is different. Offering a way to settle EMA product information rather than another opinion about it.…
Time to steady state after a dose increase Replied, post #105 · Pharmacology › Pharmacokinetics · 5 Nov 2024 · 0 likes Dose proportionality across the studied range means dose arithmetic behaves the way you would naively expect. It is worth checking whether it holds for a given compound…
Transporting a vial for a weekend away Replied, post #7 · Practice › Storage & stability · 25 Oct 2024 · 15 likes Building on post #6 rather than restating it. Clarity is a weak test. A solution can lose a significant fraction of its active content to degradation or adsorption…
Second pass at: Food noise reducing and the disorientation that can follow Replied, post #46 · Wellbeing › Mental health · 23 Oct 2024 · 1 like Building on post #45 rather than restating it. Posting my Food noise numbers with the method attached so they can be discounted properly. Uncontrolled, unblinded, and…
Requesting a page: what makes a good request — what changed since Replied, post #69 · Documentation › Wiki requests · 11 Oct 2024 · 4 likes Scope creep: if you think a page is attempting too much and should be split into multiple pages, that is a reasonable suggestion. That is the honest state of it as of…
Second pass at: Hoarding and why it makes a shortage worse Replied, post #16 · Access › Shortages · 9 Oct 2024 · 24 likes Where an alternative within the class is available, the comparison is a clinical one and the doses are not equivalent. The evidence for this is thinner than the way I…
Follow-up: A site rotation scheme that is easy enough to actually follow Replied, post #60 · Practice › Administration · 27 Sep 2024 · 0 likes If you have to inject at a different time of day than usual, that is a much smaller perturbation than it feels for a weekly compound with a week-long half-life.
Reporting a discrepancy without making an allegation Replied, post #71 · Sourcing › Vendor reports · 13 Sep 2024 · 0 likes Adding what did not work for me on reporting a discrepancy, since the failures never get written up and they are half the useful information.
[2026 update] People with a low starting BMI: where the evidence stops Replied, post #17 · Clinical › Special populations · 5 Sep 2024 · 0 likes Adding the measurement that post #14 says would settle it. Body weight at the extremes of the studied range affects exposure and the trials rarely reported enough to…