Exploration of Digestive Diseases

Table 1. Basic definitions of fragility indices

Metric index	Basic definition
Fragility index (FI)	The minimum number of event reversals (from non-event to event) required to change a statistically significant result to non-significant (p > 0.05).
Reverse fragility index (rFI) [52]	The minimum number of event reversals needed to turn a non-significant result (p ≥ 0.05) into a significant one (p < 0.05).
Fragility quotient (FQ) [44]	The FI is divided by the total sample size.
Incidence fragility index (FIq) [52]	The FI normalized by the control group event incidence rate, making fragility comparable across trials with different event rates.
Generalized fragility index (GFIq) [52, 57]	A composite fragility metric incorporating both increases and decreases in event occurrences, allowing a broader assessment of study robustness.

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Author contributions

APZ: Conceptualization, Writing—original draft, Writing—review & editing. NH: Conceptualization; Writing—review & editing. Both authors read and approved this revised submitted version.

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