Understanding, Confidence and Usefulness of Effect Size and Certainty of Evidence: A Cross-Sectional Survey Among Australian Dietitians
- 1Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, Texas, USA; Department of Surgery, Houston Methodist H
Abstract
Purpose: Interpreting treatment effect size is essential for evidence-informed dietetic care, yet understanding of this competency among dietitians remains unestablished. Methods: We conducted a web-based cross-sectional survey of Australian dietitians (October 2024-February 2025). The survey assessed their understanding of effect size, presented using three absolute estimates (risk difference [RD], risk in treatment vs risk in control groups, number needed to treat [NNT]) and two relative estimates (relative risk [RR], odds ratio [OR]). We also assessed their confidence in determining correct effect size, their perceived usefulness of effect estimates and corresponding certainty of evidence. Results: Approximately 7697 dietitians received the survey link. 27 participated and 13 completers were analyzed. Correct understanding was higher for absolute than relative estimates (30.0% vs 18.2%). Risk in treatment vs risk in control groups was understood the most (41.7%) and RD, RR and OR the least (18.2% each). Confidence was highest for RR [mean (SD): 4.18 (1.25)] and lowest for NNT [3.40 (1.17)]. Perceived usefulness was highest for OR [4.69 (1.18)] and lowest for NNT [3.75 (1.76)]. Certainty of evidence was rated useful [5.69 (1.03)]. Conclusion: Based on a small sample, preliminary evidence suggests limited understanding of effect size among Australian dietitians, highlighting the need for further training and assessment in larger sample.
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BibTeX
@misc{ghosh2026understanding,
title = {{Understanding, Confidence and Usefulness of Effect Size and Certainty of Evidence: A Cross-Sectional Survey Among Australian Dietitians}},
author = {N. R. Ghosh and E. P. Neale and B. C. Johnston},
howpublished = {medRxiv},
year = {2026},
month = nov,
doi = {10.64898/2026.11.03.26366416},
url = {https://www.medrxiv.org/content/10.64898/2026.11.03.26366416v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Understanding, Confidence and Usefulness of Effect Size and Certainty of Evidence: A Cross-Sectional Survey Among Australian Dietitians
AU - N. R. Ghosh
AU - E. P. Neale
AU - B. C. Johnston
PY - 2026
DA - 2026/11/03
PB - medRxiv
DO - 10.64898/2026.11.03.26366416
UR - https://www.medrxiv.org/content/10.64898/2026.11.03.26366416v1
AB - Purpose: Interpreting treatment effect size is essential for evidence-informed dietetic care, yet understanding of this competency among dietitians remains unestablished. Methods: We conducted a web-based cross-sectional survey of Australian dietitians (October 2024-February 2025). The survey assessed their understanding of effect size, presented using three absolute estimates (risk difference [RD], risk in treatment vs risk in control groups, number needed to treat [NNT]) and two relative estimates (relative risk [RR], odds ratio [OR]). We also assessed their confidence in determining correct effect size, their perceived usefulness of effect estimates and corresponding certainty of evidence. Results: Approximately 7697 dietitians received the survey link. 27 participated and 13 completers were analyzed. Correct understanding was higher for absolute than relative estimates (30.0% vs 18.2%). Risk in treatment vs risk in control groups was understood the most (41.7%) and RD, RR and OR the least (18.2% each). Confidence was highest for RR [mean (SD): 4.18 (1.25)] and lowest for NNT [3.40 (1.17)]. Perceived usefulness was highest for OR [4.69 (1.18)] and lowest for NNT [3.75 (1.76)]. Certainty of evidence was rated useful [5.69 (1.03)]. Conclusion: Based on a small sample, preliminary evidence suggests limited understanding of effect size among Australian dietitians, highlighting the need for further training and assessment in larger sample.
ER -