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How to determine the quality of an observational study — Whalespan

Content›Video›How to determine the quality…

How to determine the quality of an observational study

Peter Attia21m · 2023-09-07

Claims Made

41

Claims Supported

32

Support Rate

78%

Support rate

32 of 41 claims supported

32 supported9 partial / not

Claims from this content

20

✓Well SupportedThe perceived health benefits of vegetarianism may be due to 'healthy user bias'.◐Partially SupportedMeticulously logging food intake can change eating behavior, especially when logs are scrutinized.◐Partially SupportedPrimary outcomes are the main endpoints for which a study is designed and powered, while secondary outcomes are often exploratory.◐Partially SupportedIn well-designed trials, all participants in each group should receive the same amount of attention, investigator contact, and advice.Partially Supported

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Attia walks back the clinic protocol: too aggressive for healthy adults

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AV

A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

NP

N. Park

2d

Would love a "what would change this verdict" RSS feed. Sign me up if it exists.

◐

A daily recall app could potentially yield more accurate food frequency data than traditional questionnaires.

◐Partially SupportedNutritional epidemiology requires a referendum on how media interacts with study findings and more rigorous scrutiny of methodologies.

◐Partially SupportedObservational studies often associate bacon consumption with a ~30% increased risk of various health issues, including cancer and heart disease.

◐Partially SupportedThe Hawthorne effect describes how people change their behavior when they know they are being observed.

◐Partially SupportedDiet soda may not be inherently more fattening than regular soda; the association may be due to healthy user bias.

◐Partially SupportedHaving someone observe your meals can significantly impact eating behavior.

◐Partially SupportedRecall is reasonable for profound life events, such as childbirth history, over a 10-year period.

✓Well SupportedPeople who choose not to eat meat may exhibit confounding health behaviors such as less smoking, more exercise, better sleep, and higher medication compliance.

◐Partially SupportedClimate can be a confounder in observational studies, for example, linking hot chocolate consumption to skiing accidents.

◐Partially SupportedRecalling recent food intake is more reliable than recalling intake from a distant past date.

◐Partially SupportedPerformance bias, such as the Hawthorne effect, can alter participant behavior in studies.

◐Partially SupportedIn a weight loss trial, a group receiving twice-weekly counseling on potato consumption lost more weight than a calorie-restricted group that received only leaflets on calorie measurement.

◐Partially SupportedThe World Health Organization (WHO) has linked red meat and processed meat consumption to a 20-30% associated increase in risk.

◐Partially SupportedBonferroni correction is used to adjust P-values when multiple looks at the data are taken.

◐Partially SupportedRecalling smoking history might yield more accurate answers than dietary recall, potentially with supporting evidence like cigarette purchase receipts.

◐Partially SupportedRecalling specific dietary intake, such as oatmeal consumption over the past year, is difficult and prone to inaccuracy, even for individuals who closely monitor their diet.