Nutrition study design issues: important issues for interpretation.

Gardner, Christopher D.; Crimarco, Anthony; Landry, Matthew J.; Fielding-Singh, Priya

doi:10.1177/0890117120960580d

Cited by 32Statistical Methods in EpidemiologyNutritional Studies and DietMethodologies in Health Research and Practice

Nutrition study design issues: important issues for interpretation.

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Gardner, Christopher D., Crimarco, Anthony, Landry, Matthew J., Fielding-Singh, Priya·2020·American Journal of Health Promotion

DOI 10.1177/0890117120960580dPMC PMC7935659

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Diet data collection using the state-of-the-art Nutrition Data System for Research allowed us to assess and report on adherence-an important metric in free-living trials-and compare macronutrient and micronutrient intakes.
“Fifth, diet data collection using the state-of-the-art Nutrition Data System for Research allowed us to assess and report on adherence—an important metric in free-living trials53—and compare macronutrient and micronutrient intakes.”
From Cardiometabolic Effects of Omnivorous vs Vegan Diets in Identical Twins: A Randomized Clinical Trial (2023) · cites this paper as [53]
Extensive diet data collection using state-of-the-art NDS-R allowed the study to assess adherence and compare nutrient intakes.
“Seventh, extensive diet data collection using state-of-the-art NDS-R allowed us to assess adherence—an important metric in free-living trials (50)—and to compare nutrient intakes.”
From Effect of a ketogenic diet versus Mediterranean diet on glycated hemoglobin in individuals with prediabetes and type 2 diabetes mellitus: the Interventional Keto-Med Randomized Crossover Trial. (2022) · cites this paper as [50]
An important design strength was emphasizing high-quality dietary choices for both diet phases.
“Finally, we believe an important design strength was emphasizing high-quality dietary choices for both diet phases (50), as exemplified by using the WFKD for the ketogenic diet phase and by an emphasis on avoiding refined grains and added sugars for the Mediterranean diet phase.”
From Effect of a ketogenic diet versus Mediterranean diet on glycated hemoglobin in individuals with prediabetes and type 2 diabetes mellitus: the Interventional Keto-Med Randomized Crossover Trial. (2022) · cites this paper as [50]
Limitations of many of the studies highlighted in this review involve study design issues that create challenges for interpretation and comparison between studies.
“Limitations of many of the studies highlighted in this review involve study design issues that create challenges for interpretation and comparison between studies [106].”
From Benefits of low carbohydrate diets: a settled question or still controversial? (2021) · cites this paper as [106]

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Adherence to a Mediterranean diet and survival in a Greek population
Trichopoulou, A., Costacou, T., Bamia, C., & Trichopoulos, D. (2003) · New England Journal of Medicine · doi:10.1056/nejmoa025039 · Cited by 4,397 · see citing works
Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts
Estruch, R., Ros, E., Salas-Salvadó, J., Covas, M.-I., Corella, D., Arós, F., Gómez-Gracia, E., Ruiz-Gutiérrez, V., Fiol, M., Lapetra, J., et al. (2018) · New England Journal of Medicine · doi:10.1056/nejmoa1800389 · Cited by 3,616 · see citing works
Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet
Shai, I., Schwarzfuchs, D., Henkin, Y., Shahar, D. R., Witkow, S., Greenberg, I., Golan, R., Fraser, D., Bolotin, A., Vardi, H., et al. (2008) · New England Journal of Medicine · doi:10.1056/nejmoa0708681 · Cited by 2,143 · see citing works
Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake
Hall, K. D., Ayuketah, A., Brychta, R., Cai, H., Cassimatis, T., Chen, K. Y., Chung, S. T., Costa, E., Courville, A., Darcey, V., et al. (2019) · Cell Metabolism · doi:10.1016/j.cmet.2019.05.008 · Cited by 1,971 · see citing works
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“…et al. (2007)3 40% carb (Zone diet) 20 g of carbs/day for 1st 2 months and then 50 g of carbs/day for remainder (Atkins diet) 10% fat (Ornish diet) Sacks et al. (2009)4 Lowest amount of carb among 4 study diets was 35% carb Lowest amount of fat among 4 study diets was 20% fat Shai et al.…”
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Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors: A Randomized Trial
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Additional file 3 of Implementing multicomponent, eHealth-based behaviour change support within a dietary intervention trial improves adherence to study-related behaviours in healthy young adults
Worthington, A., Gillies, N. A., Hannaford, R., Roy, R., & Braakhuis, A. J. (2024) · Figshare · doi:10.6084/m9.figshare.26643307
Additional file 2 of Implementing multicomponent, eHealth-based behaviour change support within a dietary intervention trial improves adherence to study-related behaviours in healthy young adults
Worthington, A., Gillies, N. A., Hannaford, R., Roy, R., & Braakhuis, A. J. (2024) · Figshare · doi:10.6084/m9.figshare.26643304
Additional file 1 of Implementing multicomponent, eHealth-based behaviour change support within a dietary intervention trial improves adherence to study-related behaviours in healthy young adults
Worthington, A., Gillies, N. A., Hannaford, R., Roy, R., & Braakhuis, A. J. (2024) · Figshare · doi:10.6084/m9.figshare.26643301
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Authors: Gardner, C. D., Crimarco, A., Landry, M. J., & Fielding-Singh, P.
Affiliations: Stanford Medicine (US)
Stanford Prevention Research Center, Stanford Department of Medicine, Stanford University, Stanford, CA, USA
Corresponding author: Gardner, Christopher D.
ORCID: Gardner, Christopher D.
Crimarco, Anthony
Landry, Matthew J.
Venue: American Journal of Health Promotion
Publisher: SAGE Publications
Published: 2020-10-19
Volume: 34
Issue: 8
Pages: 951-954
ISSN: 0890-1171 (ISSN-L)
2168-6602
DOI: 10.1177/0890117120960580d
PMC: PMC7935659
OpenAlex: W3093324185
Cited by: 32
References: 15
Citations by year: 2026: 2 · 2025: 3 · 2024: 10 · 2023: 5 · 2022: 6 · 2021: 6
Type: journal article
Language: en
Open access: green
europepmc.org
Licence: journals.sagepub.com/page/policies/text-and-data-mining-license (tdm)
Locations: American Journal of Health Promotion (publishedVersion)
PubMed (publishedVersion)
Europe PMC (PubMed Central) (acceptedVersion)
PubMed Central (acceptedVersion)
Funders: National Heart, Lung, and Blood Institute (T32HL007034)
National Institute of Diabetes and Digestive and Kidney Diseases (P30DK116074)
Topics: Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
Health Sciences › Health Professions › Health Information Management › Methodologies in Health Research and Practice
Keywords: study interpretation, dietary assessment, study design flaws
MeSH terms: Humans, Nutritional Status, Research Design

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