Relative Age Effect in the Girls' Volleyball U18 World Championship

Exploring the structure of relative age effects research using citation network analysis

Since the 1980s, research on relative age effects (RAEs) consistently shows that relatively older individuals are advantaged in sport and other contexts. With the recent proliferation of studies on RAEs, periodic knowledge synthesis becomes imperative. Our purpose was to conduct a cross-disciplinary citation network analysis of RAEs literature to enhance our knowledge of RAEs citation structures and the interconnectivity of RAEs studies. We analysed 484 RAEs articles found in Web of Science that were published before 2022. Descriptive results revealed a 12.6% annual growth rate for total RAEs articles published since 1980. The articles appeared in 151 journals, had 1,180 unique authors, and averaged 23.9 citations received. Three theoretical/review papers had the most substantial influence on the field. For the conceptual structure of the field, it was apparent that RAEs research focused mainly on sport performance, maturity, and competition. Regarding intellectual structure, three distinct clusters of articles were cited together, and 13 authorship clusters were detected with few between-cluster connections. The results describe a field with productivity but little interconnectivity among authors and papers. We offer insights into this trend and the role that influential authors/articles have in the field.

The Relative Age Effect in Male and Female Brazilian Elite Volleyball Athletes of Varied Competitive Levels

Volleyball is a popular sport in Brazil, and the relative age effect (RAE) is known to occur within it; but less is known of how RAE relates to elite Brazilian volleyball players' age, sex, and competitive levels. We aimed to investigate RAE prevalence with data from two seasons of play among players in the Superliga A (2020/2021 and 2021/2022 seasons), and Superliga B (2021 and 2022 seasons) made available from the Brazilian Volleyball Confederation (CBV), the club's official website, or direct consultation with the CBV. After removing duplicate data, we grouped these 1,063 athletes by their dates of birth, sex, and competition level (Superliga A or B). We divided players' birth dates into quarters (Q1: January-March, Q2: April-June, Q3: July-September and Q4: October-December) and into semesters, and we performed chi-square (χ²) tests to investigate RAE prevalence according to the players' sex and competitive level. RAE was prevalent overall (χ² = 33.198; p < .001), among males (χ² = 24.48; p < .001) and females (χ² = 11.23; p < .011). Regarding competition level, RAE was evident among males in both Superliga A (χ² = 14.581; p = 0.002), and B (χ² = 13.985; p = 0.003), and among females in Superliga B (χ² = 9.204; p = 0.027), but not Superliga A (χ² = 4.012; p = 0.26). Thus, the RAE phenomenon operated differently for male and female Brazilian volleyball players according to their competitive level. We discuss the implications of these findings.

Prevalence of the Relative Age Effect in Elite Brazilian Volleyball: An Analysis Based on Gender, the Playing Position, and Performance Indicators

Athletes born closer to an arbitrary cut-off date are more likely to reach an elite level in sport, which is supported by a phenomenon called the relative age effect (RAE). It is important to determine whether this phenomenon is present in a sport to minimize this selection bias. This study aimed to investigate the prevalence of RAE in elite volleyball athletes, considering the influence of gender, the playing position (Setter, Middle, Libero, Opposite, and Outside Hitter) and the performance level (attack points, aces, and block points). The sample comprised 203 male and 193 female athletes competing in the Superliga A in the 2020/2021 season, which was equivalent to all of the teams of the championship. The data collection was performed during May and June, 2021. Athletes were organized according to gender, the playing position, and performance in the Superliga. For performance variables, athletes were separated based on the median value (90.0), and classified as high- or low-performance. Chi-squared tests were performed to verify differences between birth date distributions in relation to the aforementioned variables. Results indicated overrepresentation of relatively older male athletes (Q1 = 35.96%; Q2 = 27.59%; Q3 = 19.21%; Q4 = 17.24%), especially in Middles, Opposites, and Outside Hitters, regardless of their performance level. Considering females, no differences were found. Our findings suggest that RAE operates differently for men and women in elite Brazilian volleyball. The characteristics of the games played by male and female elite athletes may lead to different talent selection processes, affecting the likelihood of RAE prevalence.

Are the Player Selection Process and Performance Influenced by Relative Age Effect in Elite Women's Handball?

The relative age effect (RAE) is a phenomenon present in team sports, but it does not influence each gender to the same extent. This study aimed to examine the RAE and its relation to performance in international women's handball competitions (2017/18 World Championships). The sample was composed of 1,096 female players distributed into three categories: youth or under 18 (n = 369); junior or under 20 (n = 328) and senior (n = 399). The teams were divided into four groups based on their final position (medalist, quarter-finalist, eight-finalist and bottom-eight teams). The birthdate distribution (trimesters and semesters) was analysed according to the competition category and the playing position. Differences between the expected and observed birthdate distribution were checked using the chi-square statistical test followed by the calculation of the odds ratio. The results revealed, by trimester, the presence of the RAE in the youth (x²(7) = 87.22; p < 0.001) and junior (x² (7) = 33.12; p < 0.001) categories, with no impact on senior (p > 0.05). The effect size was relatively strong in the youth category (Vc = 0.48). By semester, the prevalence of the RAE was also found in the senior category (p < 0.05). According to the playing position, the RAE was especially detected in 'goalkeeper' (p < 0.01) and 'centre-back' (p < 0.05) positions, both in U-18 and U-20 categories. Surprisingly, this effect also appeared in the 'back' players in the senior category (p < 0.05). A prevalence of the RAE was identified in teams with a higher final position, but interestingly had a greater impact in the quarter-finalist teams (p < 0.001) than in the medalist teams (p < 0.01). The findings demonstrated that the RAE tends to decrease as the chronological age of players increases, demonstrating a strong presence according to collective performance in international women's handball.