Table 1.
Characteristics of included studies.
| First author, year | Country | Population | Sample size | Male (n, %) | Age range (years) | Mean age (SD) | Overall quality assessment | QT correction methods used |
|---|---|---|---|---|---|---|---|---|
| Aihoshi (1995) 18 | Japan | Young people | 5,786 | 2741, 47.36% | 15 | 15 | Fair |
Bazett Fridericia Others (not Framingham or Hodges) |
| Gervasi (2017) 19 | Italy | Athletes | 373 | 373, 100% | 13−35 | 14.3 (5.6) | Fair |
Bazett Fridericia Framingham Hodges |
| Griffet (2016) 20 | France | Athletes | 446 | 237, 53.1% | 10−18 | 14.8 (1.8) | Fair |
Bazett Fridericia Framingham Hodges |
| Hadley (2019) 21 | United States | Athletes and young people | 31 588 | 17 318, 55% | 12−35 | 16.9 (2.7) | Fair |
Bazett Fridericia Framingham Hodges |
| Huttin (2018) 22 | France | Athletes | 2484 | 2848, 100% | 16−40 | Not provided | Fair |
Bazett Fridericia |
| Karjalainen (1994) 23 | Finland | Young people | 324 | 324, 100% | 18−28 | Not provided | Fair |
Bazett Fridericia Framingham |
| Kujanik (2013) 24 | Slovakia | Young people | 138 | 0, 0% | 18−24 | Not provided | Fair |
Bazett Fridericia Hodges |
| Oo (2016) 25 | United States | Young people | 106 | 104, 98% | NR | 29.7 (2.7) | Fair |
Bazett Fridericia Framingham Hodges |
| Pickham (2016) 26 | United States | Athletes | 2077 | 1288, 62% | 14−35 | 19 (3.5) | Fair |
Bazett Fridericia Framingham Hodges |
| Wong (2012) 27 | France | Athletes and young people | 1179 | 752, 64% | 17−38 | NR | Fair |
Bazett Fridericia Framingham Hodges Linear exponential regression |
Abbreviations: NR, not reported; SD, standard deviation.