Posting this under the heading it deserves: Cleaning a self-reported dataset and what you throw away — what changed since Everything below is what sits behind that. Posting the method first, because I know what the first three replies will otherwise be. Column: C18, 2.1 x 100 mm, 1.7 um Mobile phase: 0.1% TFA in water / 0.1% TFA in acetonitrile Gradient: 5% to 54% organic over 28 minutes Detection: 280 nm Injection: 18 uL Sample: retatrutide, reconstituted to 2.0 mg/mL, injected within an hour The main peak integrates at 99.4% of total area. There is a small feature on the trailing edge that I cannot decide is a shoulder or a baseline artefact, and that is what I am actually asking about.

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Cleaning a self-reported dataset and what you throw away — what changed since

Data & Tools › Datasets observational data site feedback data table confounding

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Solved by PharmNotes_Whitfield in post #3

Picking up post #2: that is the part I would want checked first. Collection methods: ask how the data were collected. Longitudinal tracking over months is stronger than retrospective recall. Prospective measurement (done while experiencing something) is stronger than memory afterward.

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h.mbekiTL2 Moderator3 Jul 2026#1

Posting this under the heading it deserves: Cleaning a self-reported dataset and what you throw away — what changed since Everything below is what sits behind that.

Posting the method first, because I know what the first three replies will otherwise be.

Column: C18, 2.1 x 100 mm, 1.7 um
Mobile phase: 0.1% TFA in water / 0.1% TFA in acetonitrile
Gradient: 5% to 54% organic over 28 minutes
Detection: 280 nm
Injection: 18 uL
Sample: retatrutide, reconstituted to 2.0 mg/mL, injected within an hour

The main peak integrates at 99.4% of total area. There is a small feature on the trailing edge that I cannot decide is a shoulder or a baseline artefact, and that is what I am actually asking about.

0 likes 25d

s.cabreraTL2 Moderator18 Jul 2026#2

On the opening post — agreed on the reasoning, with one qualification.

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 actually address it. Both are the norm here and both matter more than they sound.

2 likes 10d

PharmNotes_WhitfieldTL4Pharmacist Solution28 Jul 2026#3

h.mbeki, post #1: Posting this under the heading it deserves: Cleaning a self-reported dataset and what you throw away — what changed since Everything below is what sits behind that. Posting the method first, because I know what the first three replies will otherwise be. Column: C18, 2.1 x 100 mm, 1.7 um Mobile phase: 0.1% TFA in water / 0.1% TFA in… Go to post

Picking up post #2: that is the part I would want checked first.

Collection methods: ask how the data were collected. Longitudinal tracking over months is stronger than retrospective recall. Prospective measurement (done while experiencing something) is stronger than memory afterward.

14 likes in reply to #1 1h

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Revisiting: Sample size in a voluntary survey: the selection problemData & Tools › Datasets · 2 replies

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