Table 2

Study methodology

First author, publication year	RRR method	Method of record selection	Method of review*	> 1 AE/ patient	Commission/omission	Data on IRR outcome	Time frame of AE detection, in addition to index admission	AE definition†	Preventability reporting
General care population, GTT/TT methodology
Chapman, 201440	TT	Random	2-stage; (1) 40 triggers, trained reviewer; (2) trained physician	Yes	Both	No	Before; after	Wider than IHI	No
Davenport, 201741	GTT	Random	2-stage; (1) 52 triggers, trained physicians; (2) trained physicians	Yes	NS	Yes	Before NS; after	IHI like	No
Fajreldines, 201945	TT	Random	NS	Yes	NS	No	NS	NS	No
Kirkendall, 201250	GTT	Random	2-stage; 1) 53 triggers, trained nurses; (2) physician	Yes	Commission only	Yes	Before; after	IHI like	No
Matlow, 201254–56‡	TT	Random	2-stage; (1) 35 triggers, trained nurses, health record technologists/medical record technicians; (2) trained physicians	Yes	Both	Yes	Before; after	HMPS like	Yes
Paredes Esteban, 201558	GTT	Unclear	2-stage; (1) NS, trained nurses; (2) trained physicians	Yes	NS	No	Only index	HMPS like	No
Salimath, 202046 60	TT	Random	2-stage; (1) 40 triggers, trained pharmacists; (2) trained physicians	Yes	NS	No	Before NS; after	Other	No
Shah, 200951 61	TT	Random	2-stage; (1) 43 triggers, physicians; (2) physicians	Yes	Both	Yes	Before; after NS	Wider than IHI	No
Solevag, 201463	TT	Convenience	Unclear; 39 triggers, trained physician	Yes	NS	No	Before; after	Wider than IHI	No
Stockwell, 201566	TT	Random	2-stage; (1) 51 triggers, trained nurses, pharmacists; (2) trained physicians	Yes	Both	No	Before NS; after	IHI like	Yes
Stockwell, 201813 67	TT	Random	2-stage; (1) 27 triggers, trained nurses; (2) trained physicians	Yes	NS	Yes	Before; after	IHI like	Yes
Stroupe, 201868	TT	Random	2-stage; (1) 54 triggers, trained nurses; (2) trained physicians	Yes	Both	Yes	Before NS; after	Wider than IHI	Yes
Unbeck, 201414	TT	Random	2-stage; (1) 88 triggers, trained nurses; (2) trained physicians	Yes	Both	Yes	Before; after	Wider than IHI	Yes
General care population, HMPS methodology
Brennan, 199111 47 52	HMPS	Random	2-stage; (1) 18 criteria, trained nurses, medical record analyst; (2) trained physicians	No§	Both	Yes	Before; after	HMPS like	No
Davis, 200242–44	HMPS	Random	2-stage; (1) 18 criteria, trained nurses; (2) trained medical officers	No§	Both	Yes	Before; after	HMPS like	Yes
Letaief, 201053	HMPS	Random	2-stage; (1) 18 criteria, trained medical student; (2) physicians	No§	Both	Yes	Before; after	Wider than IHI	Yes
Requena, 201159	HMPS	Random/total sample¶	2-stage; (1) 19 criteria, NS; (2) NS	Yes	NS	No	NS	Wider than IHI	Yes
Sommella, 201464	HMPS	Random	2-stage; (1) 16 criteria, trained physicians; (2) trained physicians	No	NS	No	Before NS; after	HMPS like	No
Soop, 200965	HMPS	Random	3-stage; (1) 18 criteria, trained nurses; (2) trained physicians; (3) member of the Scientific Council	No§	Both	Yes	Before; after	HMPS like	Yes
Wilson, 199512	HMPS	Random	2-stage; (1) 18 criteria, trained nurses; (2) trained medical officers	No§	Both	Yes	Before; after	HMPS like	Yes
Woods, 200569 70 74	HMPS	Random	2-stage; (1) 18 criteria, trained nurses; (2) trained physicians	No	Both	Yes	Before; after	HMPS like	Yes
Zegers, 200933 75	HMPS	Random	3-stage; (1) 18 criteria, trained nurses; (2–3) trained physicians	Yes	Both	Yes	Before; after	HMPS like	Yes
Intensive care population, GTT/TT methodology**
Agarwal, 201038	TT	Random	2-stage; (1) 22 triggers, trained nurses, physicians; (2) trained physician, pharmacist	Yes	Both	No	Before; after	Wider than IHI	Yes
Barrionuevo, 201039	TT	Total sample	2-stage; (1) 19 triggers, trained nurses; (2) trained physician	Yes	NS	No	NS	Wider than IHI	Yes
Hooper, 201448	TT	Random	Unclear; 22 triggers, trained investigators	Yes	Commission only	Yes	Before; after	Wider than IHI	No
Jorro-Baron, 202149	TT	Random	2-stage; (1) 37 triggers, trained PICU staff; (2) trained physicians	Yes	Both	No	NS	NS	Yes
Larsen, 20078	TT	Every seventh admission	Unclear; 46 triggers, nurses, physicians	Yes	NS	Yes	NS	NS	Yes
Maziero, 202057	TT	NS	2-stage; (1) NS, reviewer; (2) physician	Yes	NS	No	NS	NS	No
Sharek, 200662	TT	Random	2-stage; (1) 17 triggers, trained nurses; (2) trained physician	Yes	Both	No	NS	Wider than IHI	Yes
Ventura, 201271	TT	Total sample	Unclear; 14 triggers, researcher	Yes	NS	No	NS	Wider than IHI	Yes
Verlaat, 201872	TT	Random	2-stage; (1) 19 triggers, trained physician; 2) trained physician	Yes	NS	Yes	Before; after	HMPS like	Yes
Vermeulen, 201473	TT	Random	2-stage; (1) 23 triggers, trained medical student; (2) medical director	Yes	Both	No	Before NS; after	Wider than IHI	No

IHI does not require any additional monitoring, treatment or hospitalisation.
*Number of review stage(s); number of triggers/screening criteria, record review training, type of reviewer(s)/review stage.
†HMPS like requires temporary or permanent disability, death or prolonged hospitalisation; IHI like requires additional monitoring, treatment or hospitalisation, or that results in death; Wider than IHI does not require any additional monitoring, treatment, or hospitalization.
‡Outcome for the total cohort, including both general and intensive care population.
§Additional data from authors.
¶This study merged paediatric data from three studies which used different sampling techniques.
**No study using the HMPS methodology included mainly intensive care patients.
AE, adverse event; GTT, Global Trigger Tool; HMPS, Harvard Medical Practice Study methodology; IHI, Institute for Healthcare Improvement; IRR, interrater reliability; NS, not specified; RRR, retrospective record review; TT, Trigger Tool.