Table 2.

Sensitivity and Specificity of Red Blood Cells or Occult Blood in Stool to Identify Shigella and Other Bacterial Causes of Diarrhea in Systematically Reviewed Studies by Setting and Age of Included Individuals (n = 26 Studies)

Setting and Study	Study Location	RBC Test	No. With Diarrhea	No. With Shigella	Sensitivity for Shigella, %	Specificity for Shigella, %	No. With Combined Bacterial Outcome	Sensitivity for Combined Bacterial Outcome, %	Specificity for Combined Bacterial Outcomea, %
LMIC children (n = 10)
Ashraf 2007 [73]	Bangladesh	FOBT	594	18	56	…	73	55	53
Bardhan 2000 [74]	Bangladesh	FOBT	1008	205	87	…	…	…	18–80
Beltinger 1997 [44]	Bangladesh	FOBT	304	38	82	…	54	69	66
Chang 2017 [46]	China	Micro	680	1	…	…	215	13	…
Huicho 1993 [16]	Peru	FOBT	446	10	70	…	58	43	62–69
Huicho 1997 [21]	Peru	FOBT	125	6	…	…	29	79	50
Ismail 1994 [30]	Indonesia	Micro	619	44	68	61	60	52	…
Korzeniowski 1979 [14]	USA, Brazil	FOBT	101	29	85	…	…	…	89
McNeely 1996 [48]	Mexico	FOBT	1040	143	…	…	173	79	64
Patwari 1993 [51]	India	Micro	533	17	…	…	60	32	89
LMIC adults only or unknown (n = 4)
Pender 2022 [54]	Thailand, Nepal	Micro	453	34b	…	…	565b	37	85
Wang 2014 [55]	China	Micro	424	90b	…	…	176b	96	97
Aly 2005 [75]	Egypt	FOBT	40	20	45	…	…	…	30
HIC children (n = 5)
Alzaher 2022 [57]	Saudi Arabia	FOBT	1985	84	…	…	1766	48	84
Ascher 1991 [58]	USA	FOBT	180	8	…	…	24	37	67
Denno 2005 [60]	USA	FOBT or Micro	226	2	…	…	12	40	96
Paccagnini 1987 [13]	Italy	FOBT	337	…	…	…	62	74–83	67
Park 2019 [31]	South Korea	FOBT	62	…	…	…	19b	61	82
HIC adults only (n = 7)
Bouckenooghe 2000 [65]	USA	FOBT	227	…	…	…	56	30	71
Lai 2016 [66]	Taiwan	FOBT	627	3b	…	…	187b	53	63
Lever 2021 [67]	UK	Micro	1450	25	…	…	269	16	94
Loosli 1985 [68]	Switzerland	FOBT	119	3	…	…	35	80	66
Scerpella 1994 [70]	USA	FOBT	92	32	37	…	36	37	82
Shastri 2008 [26]	Germany	FOBT	200	2	…	…	107	38	85
Siegel 1987 [71]	USA	FOBT	113	19	84	…	54	87	58
Tribble 2008 [72]	USA	FOBT	182	…	…	…	177	42	84

Abbreviations: FOBT, fecal occult blood test; HIC, high-income country; LMIC, low- and middle-income country; Micro, microscopy; RBC, red blood cell count; UK, United Kingdom; USA, United States.

^aRange provided if specificity was calculated based on multiple negative outcome definitions (see Supplementary Table 1 for negative outcome definitions).

^bIncludes detection by polymerase chain reaction; otherwise, detection by culture (see Supplementary Table 1 for details).