Table 3.
Summary of data-driven study characteristics.
| References | Sex of sample | Age of sample | Sample size | Country | Sport | Study design | Outcome(s) studied |
|---|---|---|---|---|---|---|---|
| Specialization Specific | |||||||
| Beese et al. (2015) | Female | Highschool | 40 | USA | Soccer | Cross-sectional | Landing error |
| Bell et al. (2016) | Male/Female | 13–18 | 302 | USA | Soccer, basketball, tennis, volleyball | Cross-sectional | Prevalence in high school |
| Bell et al. (2018b) | Male/Female | High school | 354 | USA | Volleyball, tennis, basketball, soccer | Cross-sectional | Specialization characteristics |
| Bell et al. (2018a) | Male/Female | 12–18 | 761 | USA | Soccer | Cross-sectional | Injury |
| Black et al. (2019) | Male | 18–39 | 91 | USA | Ice hockey | Retrospective | Age of specialization |
| Bridge and Toms (2013) | Male/Female | 7–18 | 1,006 | UK | Athletics, football, hockey, netball, rugby union, swimming, boxing, power lifting | Retrospective | Talent |
| Brooks et al. (2018) | Male/Female | 12–18 | 974 | USA | Baseball, basketball, cheer/dance, cross-counrty, football, gymnastics, ice hockey, lacrosse, soccer, softball, swimming, tennis, track, volleyball, wrestling | Cross-sectional | Knowledge attitudes and beliefs of specialization |
| Buckley et al. (2017) | Male/Female | 14–26 | 3,090 | USA | Did not specify | Retrospective | Rate and age of specialization, the number of months per year of single-sport training, and the athlete's perception of injury related to specialization. |
| Buhrow et al. (2017) | Male/Female | 18–23 | 102 | USA | Swimming/diving, golf, basketball, track and field/cross-country, softball, tennis, football, wrestling, soccer | Cross-sectional | Mental toughness |
| DePhillipo et al. (2018) | Male | 12 | 11 | USA | Alpine skiing | Case Report | Injury |
| DiCesare et al. (2019) | Female | Adolescent | 79 | USA | Basketball, Soccer, volley ball | Case control | Lower extremity biomechanical deficits |
| DiStefano et al. (2018) | Male/Female | 8–15 | 355 | USA | Soccer, basketball | Cross-sectional | Landing technique |
| Ferguson and Stern (2014) | Male | 16 | 1 | Canada | Baseball | Case Study | Injury |
| Ford et al. (2012) | Male/Female | Under 16 | 328 | Brazil, England, France, Ghana, Mexico, Portugal Sweden | Soccer | Retrospective | Talent |
| Gallant et al. (2017) | Male/Female | 10–11 at start | 756 | Canada | Did not specify | Longitudinal | Physical activity and participation patterns |
| Ginsburg et al. (2014) | Male | 18–39 | 708 | USA | Baseball | Retrospective | Talent |
| Hall et al. (2015) | Female | middle and high school | 357 | USA | Basketball, soccer, volleyball | Retrospective | Injury |
| Hill (1993) | Male | adults | 152 | USA | Baseball | Retrospective | Talent |
| Jayanthi et al. (2015) | Male/Female | 7–18 | 1,190 | USA | Did not specify | Clinical case control | Injury |
| Jayanthi et al. (2018) | Male/Female | 7–18 | 1190 | USA | Did not specify | Cohort study | Injury, SES |
| Larson et al. (2019) | Male/Female | 12–13 | 137 | Canada | Swimming | Retrospective | Psych, burnout and dropout |
| Martin et al. (2017) | Male/Female | College students | 1,041 | USA | Football, track and field, soccer, cross country, swimming, diving, baseball, wrestling, basketball, golf, tennis, rowing, gymnastics, volleyball, field, hockey, softball, figure skating | Retrospective | Prior sport experience, importance of specialization and Talent |
| McDonald et al. (2019) | Did not specify | University/Olympic | 143 | USA | wrestling | Descriptive epidemiological study | Injury |
| McFadden et al. (2016) | Male | 13–18 | 61 | Canada | Ice hockey | Case control | Psychological needs satisfaction, mental health |
| McGuine et al. (2017) | Male/Female | High school | 1,544 | USA | Baseball/softball, basketball, football, soccer, tennis, track/cross-country, volleyball, wrestling, | Prospective | Injury |
| McLeod et al. (2019) | Male/Female | 12–18 | 746 | USA | Soccer | Cross-sectional | Soccer participation and specialization characteristics |
| Mendes et al. (2018) | Male | Under 19 under 21 | 78 | Brazil | Volleyball | Retrospective | Talent |
| Miller et al. (2017) | Male/Female | High school | 295 | USA | Basketball, soccer, volleyball, tennis | Cross-sectional | Anterior y balance performance, sex |
| Moseid et al. (2019) | Male/Female | 16 | 259 | Norway | Did not specify | Cross-sectional | Injury and illness |
| Noble and Chapman (2018) | Male | Adults | 519 | Marathon | Retrospective | Talent | |
| Padaki et al. (2017a) | Male/Female | Youth | 201 | USA | Soccer, basketball, baseball/softball, lacrosse, cross-country/track and field, football, swimming, tennis | Cross-sectional | Parental influence |
| Padaki et al. (2017b) | Male/Female | 7–18 | 235 | USA | Soccer, basketball, baseball/softball, lacrosse, cross-country/track and field, football, hockey, volleyball, swimming, tennis, gymnastics | Descriptive epidemiological study | Factors for specializing |
| Pantuosco-Hensch (2010) | Male/Female | 17–23 | 469 | USA | Lacrosse, soccer, swimming, tennis | Retrospective | Perceptions of ES |
| Pasulka et al. (2017) | Male/Female | 7–18 | 1190 | USA | Soccer, basketball, volleyball, baseball/softball, football, cheer, hockey, lacrosse, badminton, tennis, gymnastics, dance, swimming, wrestling, track andfield, cross-country, martial arts, diving, figure skating, horseback riding, downhill skiing, fencing, golf | Clinical case control | Injury |
| Patel and Jayanthi (2018) | Male/Female | 8–15 | 50 child 42 parents | USA | Tennis, gymnastics, soccer, basketball, swimming, football, golf, wrestling, track | Case control | Health related quality of life |
| Post et al. (2017c) | Male/Female | 12–18 | 2011 | USA | Soccer, basketball, swimming/diving, ice hockey, volleyball, track/cross-country, lacrosse, baseball, football, softball, cheer/dance, gymnastics, tennis, wrestling | Case control study | Injury |
| Post et al. (2017b) | Male/Female | College students | 343 | USA | Basketball, golf, ice hockey, soccer, tennis, football, softball, wrestling, volleyball | Retrospective | Talent |
| Post et al. (2017a) | Male/Female | Grades 9–12 | 1,544 | USA | Gymnastics, ice hockey, lacrosse, soccer, swimming, tennis, track, volleyball, wrestling | Cross-sectional | Injury and sex |
| Rugg et al. (2018) | Male | Adults | 237 | USA | Basketball | Descriptive epidemiological study | Injury and performance |
| Russell (2014) | Male/Female | 17–22 | 200 | USA | Basketball, softball, soccer, football, baseball, volleyball, tennis, track cheer, gymnastics, dance, swimming, wrestling, badminton, bowling, boxing, hockey, mixed martial arts, tae kwan do | Retrospective | Physical activity and sport motivation |
| Russell and Limle (2013) | Male/Female | 18–22 | 153 | USA | Baseball, basketball, cheer, cross-country, football, gymnastics, ice hockey, soccer, softball, swimming, track, volleyball, wrestling, golf | Retrospective | Physical activity and sport motivation |
| Russell and Molina (2018) | Female | High school | 77 | USA | Soccer, volleyball, tennis | Cross-sectional | Motivation and burnout |
| Santos et al. (2015) | Male/Female | College students | 34 | Portugal | Basketball, football, rugby | Case control | Transfer |
| Santos et al. (2017) | Male/Female | College students | 76 | Portugal | Soccer, basketball, volleyball, indoor soccer, handball, rugby, roller hockey, swimming, table tennis, karate, athletics, trampoline, gymnastics, canoeing, kickboxing, tennis, dance, judo, pentathalon, badminton, equestrian, bodyboarding | Cross-sectional | Basketball skills |
| Storm et al. (2012) | Male/Female | 18–40 | 17 | Denmark | Swimming, sailing, orienteering, golf, gymnastics, handball, soccer, badminton, kayak, rowing | Retrospective | Talent and culture |
| Strachan et al. (2009) | Male/Female | 12–16 | 74 | Canada | Swimming, artistic gymnastics, rhythmic gymnastics, diving | Case control | Sport experiences, personal development, and sport outcomes, namely enjoyment and burnout |
| Swindell et al. (2019) | Over 18 | 303 | USA | All NCAA division 1 sport | Cross-sectional | Motivation for specializing and age of specializing | |
| Wilhelm et al. (2017) | Male | 22–40 | 102 | USA | Baseball | Descriptive epidemiological study | Injury and effectiveness |
| Specialization General | |||||||
| Arede et al. (2019) | Both | Under 13 | 68 | Portugal | Basketball | Retrospective | Talent |
| Baker et al. (2005) | Male | 24–40 | 28 | Canada | Triathlete | Retrospective | Talent |
| Coutinho et al. (2015) | Both | 23 or older | 60 | Portugal | Volleyball | Retrospective | Talent |
| Cupples et al. (2018) | Male | 18–34 | 224 | Australia | Rugby | Retrospective | Talent |
| Fransen et al. (2012) | Male | 6–12 | 735 | Belgium | Did not specify | Cross-sectional | Physical fitness, motor coordination |
| Güllich (2014) | Male | Adults | 54 | Germany | Field hockey | Retrospective | Talent |
| Güllich (2017) | Both | 25–30 | 166 | Germany | All Olympic sports | Retrospective | Talent |
| Güllich and Emrich (2014) | Both | Olympic athletes | 1,558 | Germany | All Olympic sports | Retrospective/longitudinal | Talent |
| Güllich and Emrich (2013) | Both | Adults | 695 | Germany | All Olympic sports | Retrospective | Talent |
| Hendry and Hodges (2018) | Male | 15–20 | 102 | UK | Soccer | Retrospective | Talent |
| Leite and Sampaio (2012) | Male | 7–35 | 1,170 | Portugal | Basketball | Retrospective | Talent |
| Leite et al. (2009) | Male | Adults | 112 | Portugal | Roller-hockey, soccer, volleyball, basketball | Retrospective | Talent |
| Leite et al. (2013) | Male | Older than 24 | 120 | Portugal | Basketball | Retrospective | Talent |
| Livingston et al. (2016) | Both | 7–11 | 59 | USA | Soccer | Cross-sectional | Parents perceptions and reasons for participating |
| Moesch et al. (2013) | Both | Adults | 185 | Denmark | Soccer, handball, ice hockey, volleyball | Retrospective | Talent |
| Moesch et al. (2011) | Both | Adults | 243 | Denmark | CGS sports | Retrospective | Talent |
| Sieghartsleitner et al. (2018) | Did not specify | u13–u18 | 294 | Switzerland | Soccer | Retrospective | Talent |
| Sugimoto et al. (2019) | Female | 12–18 | 236 | USA | Did not specify | Cross-sectional | Injury |
| Wall and Côté (2007) | Male | 13–15 | 12 | Canada | Ice hockey | Retrospective | Dropout and investment |
| Zibung and Conzelmann (2013) | Male | Adults | 159 | Switzerland | Soccer | Retrospective | Talent |