Common Study Designs of Nutrition Clinical Trials: Review of the Basic Elements and the Pros and Cons
Review of The Basic Elements and The Pros and Cons
Abstract
Introduction: Nutrition Clinical Trials (NCTs) are pivotal in establishing causal links between nutritional interventions and chronic diseases. This review comprehensively examines prevalent clinical trial designs, emphasizing their strengths and limitations. The goal is to provide insights into the selection and optimization of these designs for dietary intervention studies.
Methods: Various study designs in NCTs are explored, including quasi-experimental designs, double-blind randomized placebo-controlled trials for nutrient/functional foods supplementation, community-based lifestyle interventions, pragmatic nutrition interventions, and field trial projects. The characteristics, advantages, and challenges of each design are discussed. Real examples are presented to illustrate how these designs can be tailored and optimized for dietary intervention studies.
Results: Parallel randomized clinical trials are acknowledged as the gold standard, despite requiring substantial sample sizes and having inherent limitations. Cross-over NCTs emerge as valuable for assessing temporary treatment effects while mitigating potential confounders and interpatient variability. However, they may not be suitable for acute diseases and progressive disorders, and attrition rates can be higher. Multi-arm randomized designs offer increased study power with a lower sample size but necessitate more intricate design, analysis, and result reporting.
Conclusion: In conclusion, each study design in NCTs comes with its set of strengths and limitations. The selection of an appropriate design should consider determinants and common considerations to provide robust evidence for establishing cause-and-effect associations or assessing the safety and efficacy of food products in nutrition research. This comprehensive understanding aids researchers in making informed choices when planning and conducting nutrition clinical trials.
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13. Woodside J WR, Patterson CC., McKinley M.C. Study Design: Intervention Studies. Nutrition Research Methodologies2015. p. 28-47.
14. Heaney RP. Guidelines for optimizing design and analysis of clinical studies of nutrient effects. Nutr Rev. 2014;72(1):48-54.
15. Bahadoran Z, Mirmiran P, Hosseinpanah F, Rajab A, Asghari G, Azizi F. Broccoli sprouts powder could improve serum triglyceride and oxidized LDL/LDL-cholesterol ratio in type 2 diabetic patients: a randomized double-blind placebo-controlled clinical trial. Diabetes Res Clin Pract. 2012;96(3):348-54.
16. Byrd-Bredbenner C, Wu F, Spaccarotella K, Quick V, Martin-Biggers J, Zhang Y. Systematic review of control groups in nutrition education intervention research. The international journal of behavioral nutrition and physical activity. 2017;14(1):91-.
17. Neufeld LM, Baker S, Garrett GS, Haddad L. Coverage and Utilization in Food Fortification Programs: Critical and Neglected Areas of Evaluation. The Journal of Nutrition. 2017;147(5):1015S-9S.
18. Berg AO, Atkins D, Tierney W. Clinical practice guidelines in practice and education.J Gen Intern Med. 1997;12 Suppl 2(Suppl 2):S25-33.
19. Adams SH, Anthony JC, Carvajal R, Chae L, Khoo CSH, Latulippe ME, et al. Perspective: Guiding Principles for the Implementation of Personalized Nutrition Approaches That Benefit Health and Function. Adv Nutr. 2020;11(1):25-34.
20. Pereira VC, Silva SN, Carvalho VKS, Zanghelini F, Barreto JOM. Strategies for the implementation of clinical practice guidelines in public health: an overview of systematic reviews. Health Research Policy and Systems. 2022;20(1):13.
21. Coulston A. Research and applied methods for observational and inervention studies. Nutrition in the Prevention and Treatment of Disease. Secound ed. Santa Fe …; 2008.
22. Shamley D, Wright B. A comprehensive and practical guide to clinical trials: Academic Press; 2017.
23. Santini A, Cammarata SM, Capone G, Ianaro A, Tenore GC, Pani L, et al. Nutraceuticals: opening the debate for a regulatory framework. British journal of clinical pharmacology. 2018;84(4):659-72.
24. Poston L, Briley AL, Barr S, Bell R, Croker H, Coxon K, et al. Developing a complex intervention for diet and activity behaviour change in obese pregnant women (the UPBEAT trial); assessment of behavioural change and process evaluation in a pilot randomised controlled trial. BMC Pregnancy Childbirth. 2013;13:148.
25. Boushey CJ, Coulston AM, Rock CL, Monsen E. Nutrition in the Prevention and Treatment of Disease: Elsevier; 2001.
26. Younge JO, Kouwenhoven-Pasmooij TA, Freak-Poli R, Roos-Hesselink JW, Hunink MM. Randomized study designs for lifestyle interventions: a tutorial. Int J Epidemiol. 2015;44(6):2006-19.
27. Clancy MJ. Overview of research designs. Emerg Med J. 2002;19(6):546-9.
28. Spieth PM, Kubasch AS, Penzlin AI, Illigens BM-W, Barlinn K, Siepmann T. Randomized controlled trials - a matter of design. Neuropsychiatric disease and treatment. 2016;12:1341-9.
29. Schork NJ, Goetz LH. Single-Subject Studies in Translational Nutrition Research. Annual review of nutrition. 2017;37:395-422.
30. James EL, Stacey FG, Chapman K, Boyes AW, Burrows T, Girgis A, et al. Impact of a nutrition and physical activity intervention (ENRICH: Exercise and Nutrition Routine Improving Cancer Health) on health behaviors of cancer survivors and carers: a pragmatic randomized controlled trial. BMC Cancer. 2015;15(1):710.
31. Harris AD, McGregor JC, Perencevich EN, Furuno JP, Zhu J, Peterson DE, et al. The use and interpretation of quasi-experimental studies in medical informatics. Journal of the American Medical Informatics Association : JAMIA. 2006;13(1):16-23.
32. Shadish WR, Cook TD, Campbell DT. Experimental and quasi-experimental designs for generalized causal inference. 2002.
33. Staudacher HM, Irving PM, Lomer MCE, Whelan K. The challenges of control groups, placebos and blinding in clinical trials of dietary interventions. Proceedings of the Nutrition Society. 2017;76(3):203-12.
34. Axelrod DA, Hayward R. Nonrandomized interventional study designs (quasi-experimental designs). Clinical research methods for surgeons: Springer; 2006. p. 63- 76.
35. Dinu M, Pounis G, Sofi F. Chapter 2 - Study Design in Experimental Settings. In: Pounis G, editor. Analysis in Nutrition Research: Academic Press; 2019. p. 23-41.
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| Files | ||
| Issue | Vol 9 No 2 (2023) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/jbe.v9i2.14623 | |
| Keywords | ||
| Nutrition clinical trial Quasi-experimental design Randomized clinical trial | ||
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How to Cite
1.
Mirmiran P, Malmir H, Bahadoran Z. Common Study Designs of Nutrition Clinical Trials: Review of the Basic Elements and the Pros and Cons. JBE. 2023;9(2):147-172.
