Niki Taouktsi1, Stefanos T Papageorgiou1, Georgios Tousinas2, Stavroula Papanikolopoulou1, Maria G Grammatikopoulou2,3, George Giannakoulas4, Dimitrios G Goulis5. 1. Medical School, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece. 2. Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Papageorgiou General Hospital, Thessaloniki, GR-56429, Greece. 3. Department of Rheumatology and Clinical Immunology, Medical School, University of Thessaly, Larissa, Greece. 4. Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece. 5. Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Papageorgiou General Hospital, Thessaloniki, GR-56429, Greece. dgg@auth.gr.
Abstract
PURPOSE: There is controversy regarding the optimal statistical method to interpret how robust is a statistically significant result. The fragility index (FI) and the reverse fragility index (RFI) are quantitative measures that can facilitate the appraisal of a clinical trial's robustness. This study was performed to evaluate the FI and RFI of randomized controlled trials (RCTs) examining nutritional interventions in patients with diabetes mellitus, focusing on cardiovascular outcomes. METHODS: A systematic search was conducted and relevant RCTs were identified in three databases. RCTs examining nutritional interventions (supplements or dietary patterns) in patients with DM with dichotomous primary endpoints involving cardiovascular outcomes were eligible. Data were extracted to compose 2 × 2 event tables and the FI and RFI were calculated for each comparison, using Fisher's exact test. Risk of bias (RoB) of the included RCTs was assessed with the Cochrane RoB 2.0 tool. RESULTS: A total of 14,315 records were screened and 10 RCTs were included in the analyses. The median FI of the paired comparisons was 3 (IQR: 2-4) and the median RFI was 8 (IQR: 4.5-17). RoB and heterogeneity were low. CONCLUSIONS: RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus appear to be statistically fragile. Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. HIGHLIGHTS: • In the evidence-healthcare era, assessing how robust statistically significant results are remains a matter of controversy. • Recently, the fragility index (FI) and reverse fragility index (RFI) were proposed to assess the robustness of randomized controlled trials (RCTs) with 2 × 2 comparisons. • When applying the FI and RFI, RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus (DM) appear to be statistically fragile. • Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. • RCTs implementing nutrition interventions among patients with DM can improve their methodology.
PURPOSE: There is controversy regarding the optimal statistical method to interpret how robust is a statistically significant result. The fragility index (FI) and the reverse fragility index (RFI) are quantitative measures that can facilitate the appraisal of a clinical trial's robustness. This study was performed to evaluate the FI and RFI of randomized controlled trials (RCTs) examining nutritional interventions in patients with diabetes mellitus, focusing on cardiovascular outcomes. METHODS: A systematic search was conducted and relevant RCTs were identified in three databases. RCTs examining nutritional interventions (supplements or dietary patterns) in patients with DM with dichotomous primary endpoints involving cardiovascular outcomes were eligible. Data were extracted to compose 2 × 2 event tables and the FI and RFI were calculated for each comparison, using Fisher's exact test. Risk of bias (RoB) of the included RCTs was assessed with the Cochrane RoB 2.0 tool. RESULTS: A total of 14,315 records were screened and 10 RCTs were included in the analyses. The median FI of the paired comparisons was 3 (IQR: 2-4) and the median RFI was 8 (IQR: 4.5-17). RoB and heterogeneity were low. CONCLUSIONS: RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus appear to be statistically fragile. Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. HIGHLIGHTS: • In the evidence-healthcare era, assessing how robust statistically significant results are remains a matter of controversy. • Recently, the fragility index (FI) and reverse fragility index (RFI) were proposed to assess the robustness of randomized controlled trials (RCTs) with 2 × 2 comparisons. • When applying the FI and RFI, RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus (DM) appear to be statistically fragile. • Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. • RCTs implementing nutrition interventions among patients with DM can improve their methodology.
Authors: Emelia J Benjamin; Salim S Virani; Clifton W Callaway; Alanna M Chamberlain; Alexander R Chang; Susan Cheng; Stephanie E Chiuve; Mary Cushman; Francesca N Delling; Rajat Deo; Sarah D de Ferranti; Jane F Ferguson; Myriam Fornage; Cathleen Gillespie; Carmen R Isasi; Monik C Jiménez; Lori Chaffin Jordan; Suzanne E Judd; Daniel Lackland; Judith H Lichtman; Lynda Lisabeth; Simin Liu; Chris T Longenecker; Pamela L Lutsey; Jason S Mackey; David B Matchar; Kunihiro Matsushita; Michael E Mussolino; Khurram Nasir; Martin O'Flaherty; Latha P Palaniappan; Ambarish Pandey; Dilip K Pandey; Mathew J Reeves; Matthew D Ritchey; Carlos J Rodriguez; Gregory A Roth; Wayne D Rosamond; Uchechukwu K A Sampson; Gary M Satou; Svati H Shah; Nicole L Spartano; David L Tirschwell; Connie W Tsao; Jenifer H Voeks; Joshua Z Willey; John T Wilkins; Jason Hy Wu; Heather M Alger; Sally S Wong; Paul Muntner Journal: Circulation Date: 2018-01-31 Impact factor: 29.690
Authors: Alison B Evert; Michelle Dennison; Christopher D Gardner; W Timothy Garvey; Ka Hei Karen Lau; Janice MacLeod; Joanna Mitri; Raquel F Pereira; Kelly Rawlings; Shamera Robinson; Laura Saslow; Sacha Uelmen; Patricia B Urbanski; William S Yancy Journal: Diabetes Care Date: 2019-04-18 Impact factor: 19.112