Table 1.
Summary of studies reporting the incidence and/or prevalence of IS
| INC or PRV | Date | Country | Latitude (oN) | Cases | Event Rate | Age-Adjusted | |
|---|---|---|---|---|---|---|---|
| Bobo et al. (1994) [15] | INC | 1987–1988 | U.S.A. | 45.55 | 11 | 0.100 | |
| Braathen & Theorell (1995) [16] | INC | 1990–1992 | Sweden | 59.24 | 1 | 0.096 | |
| Brna et al. (2001) [17] | INC | 1978–1998 | Canada | 46.34 | 75 | 0.307 | |
| Camfield et al. (1996) [18] | INC | 1977–1985 | Canada | 44.68 | 32 | 0.323 | |
| Chen et al. (2004) [19] | INC | 1985–1997 | Taiwan | 25.03 | 2 | 0.060 | |
| Cortez et al. (1997) [20] | INC | 1984–1993 | Canada | 43.65 | 76 | 0.056 | |
| Doerfer & Wasser (1987) [21] | INC | 1982–1985 | Germany | 48.55 | 3 | 0.570 | |
| Doose & Sitepu (1982) [22] | INC | 1957–1966 | Germany | 54.32 | 18 | 0.478 | |
| Dura-Trave et al. (2008) [23] | INC | 2002–2005 | Spain | 42.70 | 10 | 0.301 | |
| Eltze et al. (2013) [24] | INC | 2005–2006 | U.K. | 51.51 | 16 | 0.300 | |
| Freitag et al. (2001) [25] | INC | 1999–2000 | Germany | 49.45 | 0 | 0.000 | |
| Heijbel et al. (1975) [26] | INC | 1973–1974 | Sweden | 65.33 | 1 | 0.317 | |
| Hino-Fukuyo et al. (2009) [27] | INC | 2000–2005 | Japan | 38.27 | 45 | 0.420 | |
| Howitz & Platz (1978) [28] | INC | 1976–1977 | Denmark | 56.26 | 21 | 0.322 | |
| Hwang (2001) [29] | INC | 1997–2000 | South Korea | 35.91 | 324 | 0.168 | |
| Joensen (1986) [30] | INC | 1970–1980 | Denmark | 61.89 | 4 | 0.467 | |
| Lee & Ong (2001) [31] | INC | 1998–1999 | Singapore | 1.35 | 9 | 0.310 | |
| Loiseau et al. (1990) [32] | INC | 1984–1985 | France | 44.85 | 8 | 0.535 | |
| Lommi et al. (2010) [33] | INC | 1997–2006 | Finland | 60.17 | 48 | 0.376 | |
| Ludvigsson et al. (1994) [34] | INC | 1981–1990 | Iceland | 64.96 | 13 | 0.302 | |
| Matsuo et al. (2001) [35] | INC | 1989–1998 | Japan | 32.74 | 47 | 0.310 | |
| Olafsson et al. (2005) [36] | INC | 1995–1999 | Iceland | 64.96 | 6 | 0.474 | |
| Primec et al. (2002) [37] | INC | 1985–1995 | Slovenia | 46.15 | 47 | 0.206 | |
| Rantala & Putkonen (1999) [38] | INC | 1976–1993 | Finland | 65.01 | 37 | 0.410 | |
| Riikonen (1995) [39] | INC | 1960–1991 | Finland | 60.22 | 209 | 0.425 | |
| Saemundsen et al. (2007) [40] | INC | 1981–1998 | Iceland | 64.96 | 25 | 0.338 | |
| Sarsenbayeva et al. (2015) [41] | INC | 2013–2014 | Kazakhstan | 48.02 | 60 | 0.154 | |
| Schmitt et al. (1996) [42] | INC | 1991–1991 | Germany | 51.26 | 4 | 0.180 | |
| Shields et al. (1988) [43] | INC | 1967, 1972 | Denmark | 56.26 | 80 | 0.513 | |
| Sidenvall & Eeg-Olofsson (1995) [44] | INC | 1987–1991 | Sweden | 61.38 | 57 | 0.450 | |
| Trevathan et al. (1999) [45] | INC | 1975–1977 | U.S.A. | 33.75 | 20 | 0.290 | |
| Tsuboi (1988) [46] | INC | 1974–1980 | Japan | 35.67 | 3 | 0.175 | |
| Van Den Berg et al. (1969) [47] | INC | 1960–1968 | U.S.A. | 37.80 | 3 | 0.162 | |
| Vardi et al. (2005) [48] | INC | 1981–1997 | Israel | 32.02 | 31 | 0.220 | |
| Verity et al. (1992) [49] | INC | 1970–1980 | U.K. | 55.38 | 3 | 0.187 | |
| Wendt et al. (1985) [50] | INC | 1966–1966 | Finland | 66.47 | 7 | 0.581 | |
| Wirrell et al. (2011) [51] | INC | 1980–2004 | U.S.A. | 44.00 | 9 | 0.198 | |
| Young (2001) [52] | INC | 1998–1999 | Taiwan | 23.70 | 41 | 0.074 | |
| Zarrelli et al. (1999) [53] | INC | 1980–1984 | U.S.A. | 44.01 | 0 | 0.000 | |
| Beilmann et al. (1999) [54] | PRV | 1997 | Estonia | 58.38 | 8 | 0.0138 | 0.0139 |
| Bobo et al. (1994) [15] | PRV | 1988 | U.S.A. | 45.55 | 21 | 0.0028 | 0.0028 |
| Chen et al. (2004) [19] | PRV | 1997 | Taiwan | 25.03 | 142 | 0.0065 | 0.0065 |
| Cowan et al. (1989) [55] | PRV | 1983 | U.S.A. | 35.01 | 23 | 0.0327 | 0.0328 |
| Dura-Trave et al. (2012) [56] | PRV | 2009 | Spain | 42.70 | 24 | 0.0396 | 0.0397 |
| Endziniene et al. (1997) [57] | PRV | 1995 | Lithuania | 54.90 | 3 | 0.0072 | 0.0066 |
| Eriksson & Koivikko (1997) [58] | PRV | 1992 | Finland | 61.50 | 25 | 0.0578 | 0.0580 |
| Granieri et al. (1983) [59] | PRV | 1978 | Italy | 44.89 | 1 | 0.0221 | 0.0222 |
| Ishida (1985) [60] | PRV | 1975 | Japan | 34.66 | 41 | 0.0225 | 0.0226 |
| Joensen (1986) [30] | PRV | 1980 | Denmark | 61.89 | 4 | 0.0917 | 0.0917 |
| Koul et al. (1988) [61] | PRV | 1986 | India | 33.70 | 4 | 0.0628 | 0.0628 |
| Kurth et al. (2010) [62] | PRV | 2006 | U.S.A. | 37.09 | 59 | 0.0042 | 0.0009 |
| Kwong et al. (2001) [63] | PRV | 1997 | China | 22.41 | 16 | 0.0142 | 0.0143 |
| Larsson & Olofsson (2006) [64] | PRV | 2000 | Sweden | 59.86 | 4 | 0.0135 | 0.0136 |
| Maremmani et al. (1991) [65] | PRV | 1985 | Italy | 43.78 | 0 | 0.0000 | 0.0000 |
| Oka et al. (2001) [66] | PRV | 1994 | Japan | 34.66 | 6 | 0.0031 | 0.0031 |
| Olafsson & Hauser (1999) [67] | PRV | 1993 | Iceland | 64.96 | 2 | 0.0223 | 0.0223 |
| Sidenvall et al. (1996) [68] | PRV | 1985 | Sweden | 65.33 | 3 | 0.0180 | 0.0181 |
39 incidence (INC) and 18 prevalence (PRV) data points were abstracted from 54 studies [15–68]. For incidence studies, date refers to the period of observation and event rate is the number of new cases per 1000 live births. For prevalence studies, date refers to the prevalence point, event rate is the age-specific prevalence, and age-adjustment lists the age-standardized figure per 1000 population