Investigator | Population | Subjects | Signs % | Symptoms % | |||
---|---|---|---|---|---|---|---|
 |  | Sample Size | Females | Males | Age |  |  |
Siebert 1975[45] | Germany | 232 | - | - | 12–16 | 62–80 | - |
Grosfeld et al 1977[42] | Poland | 250 | 133 | 117 | 13–15 | 68*‡ | 10 |
Williamson 1977[43] | US | 304 | 175 | 129 | 6–16 | 35 | - |
Nilner 1981[17] | Sweden | 440 | 218 | 222 | 7–14 | 64 | 36 |
 |  | 309 | 162 | 147 | 15–18 | 55 | 41 |
Egermark-Eriksson[25] 1982 | Sweden | 131 | 61 | 70 | 11 | 46 | 67 |
 |  | 135 | 59 | 76 | 15 | 61 | 74 |
Gazit et al 1984[30] | Israel | 369 | 181 | 188 | 10–18 | 44‡ | 56 |
Ogura et al 1985[21] | Japan | 2198 | 1103 | 1095 | 10–18 | 9.8* | |
Dibbets 1985[24] | Holland | 165 | 94 | 71 | 7–19 | 21 | 19 |
Grosfeld et al 1985[29] | Poland | 400 | 203 | 197 | 15–18 | 68.2‡ | - |
Wanman et al 1986[33] | Sweden | 285 | 139 | 146 | 17 | 56 | 20 |
Jamsa et al 1988[26] | Finland | 109 | - | - | 10 | 41 | - |
 |  | 147 | - | - | 15 | 42 | - |
Motegi et al 1992[22] | Japan | 7337 | 4118 | 3219 | 6–18 | 12.2 | 12.2 |
Keeling et al 1994[44] | USA | 3428 | - | - | 6–12 | 10 | - |
Deng et al 1995[20] | China | 634 | 326 | 308 | 12–15 | 21.9 | - |
 |  | 905 | 424 | 481 | 16–19 | 15.9 | - |
Abdel-Hakim 1996[38] | S. Arabia | 330 | 136 | 194 | 14–21 | - | 32 |
Al Amoudi et al 1998[5] | S. Arabia | 502 | 267 | 235 | 3–7 | 16.5 | - |
Farsi N. 1999[6] | S. Arabia | 696 | - | - | 6–14 | 17.1 | 14.1 |
Thilander et al 2002[23] | Bogota | 1441 | 756 | 685 | 13–17 | 25 | 11.4 |
Farsi N. 2003[7] | S. Arabia | 734 | 420 | 314 | 12–15 | 20.2 | 31.1 |
Feteih 2005 †| S. Arabia | 385 | 230 | 155 | 12–16 | 21.3 | 34 |