Table 1.

Proposed outcomes of interest for prognostic enrichment, their potential utility, and some existing examples in patients with and without AKI

	Outcomes of interest	Proposed use	Examples
Patient without AKI	Development of any AKI	Increased surveillance for AKI Consideration of alternatives to nephrotoxic medications or procedures Closer monitoring of drug levels (i.e. vancomycin), when applicable Patient/family education Targeted novel biomarker testing	Various machine learning algorithms, including EHR-embedded [51,54,55]
	Development of severe and/or persistent AKI	In addition to above: Clinical trial enrichment for studies examining standardized AKI prevention strategies	The Renal Angina Indexa[56,57,59▪] [TIMP2]·[IGFBP7] [65]
Patient with AKI	Development of severe and/or persistent AKI	Clinical trial enrichment for studies examining novel therapies for AKI Intensive kidney supportive care (i.e. strict urine output monitoring, frequent laboratory monitoring) Patient/family counseling Targeted serial novel biomarker testing	The Renal Angina Indexa[56,57,58,59▪,60,61,62] CCL14 [64,63▪] Furosemide stress testa[60–62]
	Need for KRT	Clinical trial enrichment for studies examining timing of KRT initiation Informed clinical decision-making Patient/family counselling	Furosemide stress testa[60–62]
	Development of CKD	Clinical trial enrichment for studies examining therapies to prevent AKI/AKD to CKD transition Identify patients appropriate for outpatient nephrology follow-up Patient/family counselling	No validated tools available

[TIMP2]·[IGFBP7], the product of tissue inhibitor of metalloproteinases-2 and insulin-like growth factor-binding protein 7; AKD, acute kidney disease; AKI, acute kidney injury; CCL14, C-C motif chemokine ligand 14; CKD, chronic kidney disease; KRT, kidney replacement therapy.

^aTools that are well studied in children.