Table 15: Impact of removing outlying studies on between-study heterogeneity and summary effects.

Outlier studiesChi-square ( value)Adjusted odds ratio
(95% confidence interval)
Heterogeneity chi-square
(df, value)

GUD versus GDS2.24 (1.63–2.24)17.20 (4, .0068)
 Warner7.85 (.0051)2.65 (1.67–4.18)9.35 (3, .0250)
 Hutchinson10.08 (.0015)1.92 (1.53–2.40)7.12 (3, .0681)
 Hutchinson and Warner14.87 ( ) (.0006)2.15 (1.68–2.74)2.33 (2, .3121)
GDS0.8902 (0.73–1.09)47.36 (9, <.0001)
 Bailey6.223 (.0125)0.9209 (0.75–1.13)41.13 (8, <.0001)
 Newell9.94 (.0016)0.9279 (0.76–1.13)37.42 (8, <.0001)
 Seed23.54 (<.0001)0.9614 (0.81–1.13)23.82 (8, .0025)
 Warner26.08 (<.0001)0.8482 (0.70–1.03)21.28 (8, .0065)
 Warner and Seed37.30 ( ) (<.0001)0.91.47 (0.79–1.07)10.06 (7, .1850)
NSU0.76 (0.63–0.92)39.78 (11, <.0001)
 Lavreys4.02 (.0450)0.74 (0.61–0.89)35.76 (10, <.0001)
 Donovan4.24 (.0394)0.74 (0.61–0.92)35.54 (10, .0001)
 Cook5.94 (.0148)0.75 (0.61–0.92)33.84 (10, .0002)
 Aynaud6.25 (.0124)0.73 (0.61–0.88)33.53 (10, .0002)
 Ferris12.92 (.0003)0.80 (0.68–0.95)26.86 (10, .0027)
 Ferris and Aynaud18.78 ( ) (<.0001)0.77 (0.66–0.91)21.00 (9, .0126)
Chlamydia0.9099 (0.72–1.15)35.53 (13, .0007)
 Hart [165]10.83 (.0010)0.8605 (0.67–1.10)24.70 (12, .0163)
 Laumann18.43 (<.0001)0.9920 (0.85–1.16)17.10 (12, .1460)
 Laumann and Hart27.78 ( ) (<.0001)0.9362 (0.87–1.00)7.75 (11, .7357)
Gonorrhea1.03 (0.86–1.23)88.81 (25, <.0001)
 Lloyd5.23 (.0222) 1.05 (0.88–1.26)83.58 (24, <.0001)
 Hand9.16 ( ) (.0102)1.04 (0.86–1.25)79.55 (23, <.0001)
 Hart [165]9.42 (.0021)0.99 (0.83–1.19)79.39 (24, <.0001)
 Wilson18.26 (<.0001)1.07 (0.90–1.26)70.55 (24, <.0001)
 Cook30.10 (<.0001)0.99 (0.84–1.15)58.71 (24, .0002)
 Cook and Wilson44.32 ( ) (<.0001)1.03 (0.89–1.19)44.49 (23, .0669)
GUD1.6760 (1.39–2.02)31.09 (11, .0011)
 Tyndall4.21 (.0402)1.7326 (1.43–2.10)26.88 (10, .0027)
 Warner6.48 (.0109)1.6492 (1.33–2.05)24.61 (10, .0109)
 Barile7.64 (.0057)1.6308 (1.38–1.92)23.45 (10, .0057)
 Gray10.33 (.0013)1.7581 (1.48–2.09)20.76 (10, .0228)
 Gray and Warner12.61 ( ) (.0018)1.7385 (1.40–2.17)18.48 (9, .0300)
 Gray and Barile17.73 ( ) (.0001)1.7334 (1.51–1.99)13.36 (9, .1470)
Syphilis1.3036 (1.11–1.53)67.70 (28, <.0001)
 Todd4.18 (.0409)1.2766 (1.08–1.50)63.52 (27, <.0001)
 Wilson4.98 (.0256)1.2704 (1.08–1.49)62.72 (27, .0001)
 Buvé; Kismu5.24 (.0221)1.2804 (1.10–1.50)62.46 (27, .0001)
 Otieno5.37 (.0204)1.2685 (1.08–1.49)62.33 (27, .0001)
 Gray9.05 (.0026)1.3439 (1.14–1.58)58.65 (27, .0004)
 Hand10.95 (.0009)1.3467 (1.15–1.58)56.75 (27, .0007)
 Cook17.52 (<.0001)1.2304 (1.07–1.42)50.18 (27, .0043)
 Cook and Hand27.55 ( ) (<.0001)1.2704 (1.11–1.45)40.15 (26, .0377)
Chancroid1.3321 (0.52–1.33)59.71 (5, <.0001)
 Lloyd4.83 (.0279)1.5961 (0.5418–4.7022)54.88 (4, <.0001)
 Hand11.69 ( ) (.0029)1.4490 (0.4186–5.0152)48.02 (3, <.0001)
 Rakwar14.74 (.0001)1.5289 (0.4499–5.1956)44.97 (4, <.0001)
 Hart [69]52.23 (<.0001)0.8177 (0.5092–1.3134)7.48 (4, .1128)
Herpes; simplex virus1.1522 (0.95–1.40)152.13 (32, <.0001)
 Van Wagoner6.24 ( ) (.0442)1.1293 (0.93–1.38)145.89 (31, <.0001)
 Laumann4.76 (.0291)1.1771 (0.97–1.43)147.37 (31, <.0001)
 Ferris5.68 (.0172)1.1735 (0.96–1.43)146.45 (31, <.0001)
 Richters13.61 (.0002)1.1761 (0.97–1.27)138.52 (31, <.0001)
 Schneider26.18 (<.0001)1.1851 (0.98–1.43)1.25.95 (31, <.0001)
 Mwandi86.28 (<.0001)1.0944 (0.94–1.27)65.85 (31, .0003)
 Mwandi and Schneider99.97 ( ) (<.0001)1.1311 (0.98–1.30)51.16 (30, .0073)
Genital Warts0.8275 (0.65–1.04)37.07 (14, .0007)
 Oriel5.46 (.0194)0.7792 (0.69–0.98)31.61 (13, .0027)
 Wilson6.76 (.0093)0.7885 (0.64–0.98)30.31 (13, .0042)
 Cook11.89 (.0006)0.8696 (0.70–1.08)25.18 (13, .0218)
 Cook and Wilson18.13 ( ) (.0001)0.8365 (0.69–1.01)18.93 (12, .0901)
HPV any1.2411 (1.03–1.51)39.98 (24, .0215)
 Lajous4.09 (.0431)1.1962 (0.98–1.45)35.89 (23, .0424)
 Vardas5.56 (.0184)1.2912 (1.05–1.59)34.42 (23, .0593)
 Vaccarella8.29 (.0040)1.1806 (0.99–1.40)31.69 (23, .1068)
 Vaccarella and Vardas12.77 ( ) (.0017)1.2320 (1.02–1.48)27.21 (22, .2033)
HPV high risk1.1611 (0.94–1.45)45.27 (24, .0054)
 Oglivie4.01 (.0451)1.2162 (0.98–1.51)41.26 (23, .0111)
 Svare4.02 (.0450)1.1323 (0.92–1.40)41.25 (23, .0111)
 Lajous4.86 (.0274)1.1192 (0.90–1.39)40.41 (23, .0138)
 Vardas8.04 (.0046)1.2186 (0.98–1.52)37.23 (23, .0307)
 Vaccarella8.77 (.0031)1.1049 (0.91–1.35)36.50 (23, .0366)
 Vardas and Vaccarella15.74 ( ) (.0004)1.1602 (0.95–1.41)29.53 (22, .1303)
HPV high risk selective1.0128 (0.80–1.28)28.82 (15, .0164)
Aynaud et al. [33]4.62 (.0316)0.9727 (0.76–1.25)24.20 (14, .0433)
Vardas4.20 (.0404)1.0564 (0.82–1.37)24.62 (14, .0385)
Vaccarella9.92 (.0016)0.9553 (0.79–1.15)18.90 (14, .1689)
Vaccarella and Aynaud I15.60 ( ) (.0004)0.8747 (0.74–1.03)13.22 (13, .4306)
Vaccarella and Vardas13.13 ( ) (.0014)1.0073 (0.82–1.23)15.69 (13, .2664)
Any STI0.8627 (0.7368–1.0102)303.00 (26, <.0001)
 Auvert4.55 (.0329)0.8425 (0.7182–0.9884)298.45 (25, <.0001)
 Seed5.63 (.0177)0.8732 (0.7432–1.0266)297.37 (25, <.0001)
 Uganda5.87 (.0154)0.8410 (0.7164–0.9873)297.13 (25, <.0001)
 Urassa15.68 ( ) (.0078)0.8846 (0.7379–1.0605)287.32 (21, <.0001)
 Gebremedhin10.48 (.0012)0.8638 (0.7186–1.0383)292.52 (25, <.0001)
 Richters29.28 (<.0001)0.8713 (0.7394–1.0268)273.72 (25, <.0001)
 Ferris35.50 (<.0001)0.8822 (0.7542–1.0319)2267.50 (25, <.0001)
 Harbertson49.14 (<.0001)0.8923 (0.7665–1.0389)253.86 (25, <.0001)
 Langeni203.41 (<.0001)0.8248 (0.7358–0.9245)99.59 (25, <.0001)
 Langeni and Ferris221.08 ( ) (<.0001)0.8442 (0.7554–0.9434)81.92 (24, <.0001)
 Langeni and Harbertson234.61 ( ) (<.0001)0.8519 (0.7700–0.9426)68.39 (24, <.0001)
Any STI without Langeni0.8248 (0.74–0.92)99.59 (25, <.0001)
 Richters5.92 (.0150)0.8344 (0.7374–0.9442)93.67 (24, <.0001)
 Gebremedhin7.28 (.0070)0.8250 (0.7236–0.9406)92.31 (24, <.0001)
 Auvert7.32 (.0068) 0.8078 (0.7219–0.9039)92.27 (24, <.0001)
 Parker9.79 (.0017)0.8071 (0.7195–0.9053)89.80 (24, <.0001)
 Burundi10.37 (.0013)0.8030 (0.7182–0.8978)89.22 (24, <.0001)
 Ferris17.67 (<.0001)0.8442 (0.7554–0.9434)81.92 (24, <.0001)
 Harbertson31.20 (<.0001)0.8519 (0.7700–0.9426)68.39 (24, <.0001)
 Harbertson and Burundi40.87 ( ) (<.0001)0.8317 (0.7544–0.9157)58.72 (23, <.0001)
 Harbertson and Ferris51.08 ( ) (<.0001)0.8761 (0.794–0.9602)48.51 (23, .0014)