Table 1

Characteristics of included studies

Study	Country	Design	Study period	Size	Male (%)	Age, years	Level of experience	HUD
Aldaas et al 21	USA	Consecutive	NR	70	50	61±18	Both	Vscan
Alexander et al 22	USA	NR	April–November 2000	537	53	59	Inexperienced	Optigo
Andersen et al 23	Norway	Random	March–September 2010	108	64	69.1±14	Experienced	Vscan
Biais et al 24	France	Consecutive	February–May 2011	151	35	55±20	Experienced	Vscan
Bruce et al 9	USA	NR	NR	374	62	66	Both	SonoHeart
Coletta et al 25	Italy	Consecutive	April–June 2003	112	57	61±11	Experienced	Optigo
Cullen et al 26	USA	Consecutive	2012–2013	190	49	62±17	Experienced	Vscan
DeCara et al 27	USA	NR	NR	300	NR	NR	Experienced	Optigo
Fedson et al 28	USA	Consecutive	NR	103	NR	NR	Inexperienced	Optigo
Galasko8	UK	Consecutive	2000–2001	562	56	62±11	Experienced	Optigo
Ghani et al 29	USA	Consecutive	NR	80	51	75±13	Inexperienced	Optigo
Giusca et al 30	Romania	Consecutive	NR	56	54	60±12	Inexperienced	Acuson P10
Gulič et al 31	Slovenia	Consecutive	NR	200	43	70	Both	Vscan
Khan32	USA	Consecutive	2012–2013	240	53	71±17	Experienced	Vscan
Kirkpatrick33	USA	NR	NR	63	46	65±16	Inexperienced	Optigo
Kobal et al 34	USA	Consecutive	NR	61	62	70±19	Inexperienced	Optigo
Liebo35	USA	Consecutive	February–March 2010	97	45	68±17	Both	Vscan
López-Palmero et al 36	Spain	NR	July–December 2013	223	42	76	Inexperienced	Vscan
Lucas et al 37	USA	Consecutive	March–May 2007	322	53	56±13	Inexperienced	Micromaxx
Lucas et al 38	USA	Consecutive	2008–2009	210	55	55	Inexperienced	NR
Martin et al 39	USA	Consecutive	2004–2005	354	47	63±19	Inexperienced	Sonosite Elite
Mehta et al 40	USA	NR	NR	250	66	61±15	Experienced	Vscan
Mjølstad et al 41	Norway	Consecutive	April–June 2011	199	54	66±18	Inexperienced	Vscan
Nilsson et al 42	Sweden	NR	2016–2017	100	55	70±12	Inexperienced	Vscan
Olesen43	Denmark	NR	NR	260	49	80	Experienced	Vscan
Perez-Avraham et al 44	Israel	Consecutive	July–December 2004	85	37	59±14	Inexperienced	Optigo
Razi et al 45	USA	Consecutive	NR	50	58	57±17	Inexperienced	Vscan
Ruddox et al 46	Norway	NR	2011–2012	303	61	73	Inexperienced	Vscan
Stokke et al 13	Norway	Random	February–May 2012	72	72	65±16	Both	Vscan
Vignon et al 47	France	Consecutive	NR	55	69	61±16	Experienced	SonoHeart
Vourvouri et al 48	The Netherlands	Consecutive	NR	88	64	59±12	Experienced	SonoHeart or Optigo
Wejner-Mik et al 49	Poland	Consecutive	NR	87	67	61±16	Experienced	Lumify
Xie et al 50	USA	Consecutive	NR	100	55	59±17	Experienced	SonoHeart

HUD, handheld ultrasound devices; NR, not reported.