Annual Age Group Research Articles

BIOMARKER «PEAK HEIGHT VELOCITY» AS THE INDICATOR OF SECULAR DYNAMICS OF PHYSICAL STATUS IN INTERGROUP STUDIES/COMPARISONS

Introduction. The goal of study is the estimation of «peak height velocity» (PHV) as the marker of secular trends in addition to secular dynamics of height (H). Material and methods. The study embraces the block of samples of scholars (6/7-17 years) from Russia and former USSR, examined through the vast historical period from 1920th till nowadays, literary data and personal archives of the authors. The main attention is paid to three urban agglomerations - Moscow, Nizhniy Novgorod, Minsk. The following number of parameters is determined for each sample: the age of maximal velocity of growth dynamics of average levels of H during adolescence (APHV), determined according to the empirical patterns of annual changes of average H levels and consequent smoothing by least square method - differentially for boys and girls; and delta between parameters of boys and girls; maximal quantitative level of growth changes in cm (IPHV), different for boys and girls as well, and delta between the parameters. Results. The difference of APHV between boys and girls for each population under study is about two years - boys have delayed PHV as compared to girls in any ecological niche. Secular dynamics of APHV has nonlinear character, doesn’t decrease progressively through the whole historical interval from 1920th to 2000th, despite of permanent increase of the level of anthropogenic stress in cities under analysis, the lowest APHV is fixed in 1980th. Correlations of APHV with absolute annual H values through the age interval 6/7-17 years is systematic and high enough for boys (correlation about 0,5, determination coefficient about 0,25) and accidental for girls, being revealed for only one annual age group among 12 analyzed. Correlations of IPHV with absolute values of H are maximal at 7 years and minimal at 17 years, the level of correlations is less for girls as compared to boys. Conclusion. PHV really marks the secular somatic dynamics along with H itself as genetic marker. Correlation of APHV with absolute annual levels of H through the interval 6/7-17 years is systematic and significant for boys and accidental for girls, which witness to genetic determination of growth tempo of boys. Correlation of IPHV with absolute values of H, having highest levels at 7 years, points to the fact that height at 7 years is a real trigger of PHV parameters.

Advancing athlete development: How Percentile Comparison Methods (PCMs) can identify youth developmental profiles

ObjectivesInter-individual developmental differences confound the capability to accurately evaluate youth athletic performance, highlighting the need for considerate methodology and analytical approaches. The present study demonstrated how Percentile Comparison Methods (PCMs) were developed, tested, and applied to identify athlete developmental profiles in Australian youth swimming. DesignCross-sectional. MethodsParticipants were N = 866 female 100-metre (m) Front-Crawl swimmers, aged 9–15 years, competing at 36 Australian regional–national level long course events. At respective events, swim performance time was collated alongside, age, date of birth, and anthropometric measures to identify age group, relative age, and maturity status. Quadratic relative age and maturity status with 100-m performance regression trendlines were generated. Then, individual swim performances at a given relative age or maturity status were converted into percentile rank distributions and compared with raw (unadjusted) annual age-group performance percentile ranks. ResultsAt a cohort level, initial testing confirmed relative age and maturity-adjusted percentile rankings were associated with general rank improvements for relatively younger and later maturing swimmers compared to raw ranks (and vice versa). When assessing individual swimmer plots, where three percentile rank scores were compared and rank change threshold criteria applied, five Percentile Comparison Method profile types were identified, namely: ‘Early Developing’ (19 %); ‘Later Developing’ (18 %); ‘Consistent’ (15 %); ‘Mixed’ (38 %) and ‘Counteracting’ (10 %). Percentile Comparison Method plots helped identify developmentally (dis-)advantaged swimmers; specific factors leading to (dis-)advantage, and likely onward development trajectories. ConclusionsOverall and with practical considerations, Percentile Comparison Methods can improve the validity of youth athletic performance evaluation as well as inform athlete development programming.

Influence of Relative Age on Physical Condition and Academic Performance in Adolescents.

Annual age grouping is a common organizational strategy in academics and sports. This strategy could promote the relative effects of age, which refers to the (dis)advantages that subjects who were born in the first or last months of the year may suffer. The consequences could be minimized, resulting in better physical and/or academic results. The objective of the study was to evaluate the influence of the quarter of birth and examine the correlation between physical condition variables and academic performance. The sample included 79 students (51.90% females) 13.46 ± 0.21 years old in the second year of Obligatory Secondary Education. The physical variables of this study were explosive power, cardiorespiratory capacity, speed, flexibility, and muscle strength. They were evaluated using the horizontal jump tests, Cooper test, 50 m sprint, sit-and-reach test, and medicine ball exercises, respectively. The academic variables were obtained from the average academic grade, grouped by key competencies. An Analysis of Covariance (ANCOVA), controlling for gender, body mass, and height, revealed significant differences between male students born in the first quarter compared to those born in subsequent quarters in all physical condition variables (except for cardiorespiratory capacity). For female students, significant differences were observed only in the explosive power variable. No statistically significant intra-sex differences were evident in academic performance at any time of measurement. Additionally, moderate to large correlations were found in the physical condition and academic variables. It is concluded in relation to the need to implement diverse strategies regarding the process of developing physical conditions in adolescence that satisfy the growth needs of students based on age and sex.

Bio-banding in handball: Academy players' perceptions based on maturity status and gender.

The purpose of this study was to evaluate young male and female handball players' perceptions to the bio-banding concept. The estimated biological maturity status was assessed in a sample of 46 male and 40 female handball players (aged 14.06 ± 1.40 years) who competed in both an annual age-group and bio-banded tournament. To test the players' perception, a post-competition questionnaire was conducted. A series of ANOVA and one-sample t-tests were used in order to examine the differences in perception between the different maturity groups. An inductive thematic analysis of the qualitative data recorded in the open-ended questions was also carried out. The results showed that early-maturing boys enjoyed the bio-banding tournament more than late-maturing (p < 0.05). Conversely, no differences were found in girls (p > 0.05). Interesting conclusions could be drawn from the qualitative analysis of the players' written comments. Furthermore, a greater influence on play and leadership in male late and female early maturers, a greater physical challenge in male early maturers and an opportunity to express themselves technically and tactically in male late and female on-time maturers were observed. Thus, stakeholders must consider the different consequences of bio-banding in order to maximise the athlete's sport development process.

Do Race Results in Youth Competitions Predict Future Success as a Road Cyclist? A Retrospective Study in the Italian Cycling Federation.

The aim of this study was to investigate the relationship between youth road cycling success and becoming a professional cyclist. Specifically, the authors sought to analyze (1)the differences in the success scores in youth categories between future professional (PRO) and future nonprofessional (NON-PRO) cyclists, (2)whether relative age effect influences youth road cycling career pathways, and (3)whether youth competition success could predict a future career as a professional cyclist. The number of points gathered in the annual national ranking of 1345 Italian cyclists in the U17, U19, and U23 categories were retrospectively analyzed. Participants were divided into 2 groups: PRO (n = 43) and future NON-PRO (n = 1302), depending on whether they reached the professional level. PRO outperformed NON-PRO in all the youth categories considered (ie,U17, U19, and U23). Older cyclists within the same annual age group were not overrepresented in PRO and do not have an advantage over younger cyclists within all the competition years. The number of points gathered in youth competitions provides an indication of probability of becoming professional cyclists from U17 onward with the predictive value increasing with age category. Handling the transition to a new age group well (especially the U19-U23 transition), and therefore having success competing against older and more experienced cyclists, is an important factor for talent identification in youth cycling.

Relative Age Effects in Male Cricket: A Personal Assets Approach to Explain Immediate, Short-Term, and Long-Term Developmental Outcomes.

The purpose of this study was to adopt the Personal Assets Framework (PAF) to examine the immediate, short-term, and long-term developmental outcomes associated with relative age effects (RAEs) in male cricket. As such, this study was comprised of three aims: (a) examine the birth quarter (BQ) distribution of players throughout the England and Wales Cricket Board (ECB) national talent pathway (i.e., Regional U15, Regional U17, England U19, England Lions, England T20, England ODI, and England Test; n = 1800; immediate timescale), (b) explore the youth-to-senior transitions based on BQ and skill-set (i.e., batters and bowlers; short-term timescale), and (c) analyse the average number of games played at senior levels based on BQ and skill-set (i.e., long-term timescale). A chi-square goodness of fit test, Cramer’s V, odds ratios, and 95% confidence intervals were used to compare the BQ distributions of each cohort against the expected BQ distributions. In the immediate timescale, results showed that relatively older players were overrepresented throughout all the youth levels (p < 0.05, V = 0.16–0.30), whereas there were no differences at senior levels (p > 0.05, V = 0.05–0.15). In the short-term timescale, when the senior cohorts were compared to the expected BQ distributions based on the Regional U15 cohort, relatively younger players were more likely to transition from youth to senior levels (p < 0.05, V = 0.22–0.37). In the long-term timescale, relatively older batters were selected for more games (p < 0.05, V = 0.18–0.51), whereas relatively younger bowlers were selected for more games (p < 0.05, V = 0.17–0.39). Moving forward, it is important for researchers and practitioners to better understand how (bi)annual-age grouping shapes developmental outcomes in across different timescales (i.e., immediate, short-term, and long-term), as well as consider alternative grouping strategies and RAE solutions.

Removing maturational influences from female youth swimming: the application of corrective adjustment procedures

Introduction: Common annual age-group competition structures unintentionally introduce participation inequalities, performance (dis)advantages and selection biases due to the effect of maturational variation between youth swimmers. On this basis, there are implications for improving performance evaluation strategies. Therefore the aim was to: (1) To determine maturity timing distributions in female youth swimming; (2) quantify the relationship between maturation status and 100-m FC performance; (3) apply Maturational-based Corrective Adjustment Procedures (Mat-CAPs) for removal of maturational status performance influences.

Human Papillomavirus Vaccine Impact on Cervical Precancers in a Low-Vaccination Population

Demonstrating human papillomavirus vaccine impact is critical for informing guidelines to increase vaccination and decrease human papillomavirus‒related outcomes, particularly in states with suboptimal vaccination coverage, such as Tennessee. This study examines the trends in high-grade cervical lesion incidence among Tennessee Medicaid-enrolled women aged 18-39 years and the subset of women who were screened for cervical cancer. Using a validated claims-based model to identify incident cervical intraepithelial neoplasia Grades 2 or 3 or adenocarcinoma in situ events, annual age group‒specific incidence rates from Tennessee Medicaid billing data, 2008-2018, were calculated. Significant trends were determined by Joinpoint. Analyses were conducted in 2020. From 2008 to 2018, high-grade cervical lesion incidence significantly declined in women aged 18-20 years (average annual percentage change= -31.9, 95% CI= -38.6, -24.6), 21-24 years (average annual percentage change= -12.9, 95% CI= -22.3, -2.4), and 25-29 years (average annual percentage change= -6.4, 95% CI= -8.1, -4.6). Among screened women, rates significantly declined for ages 18-20 years (average annual percentage change= -20.3, 95% CI= -25.3, -15.0), 21-24 years (average annual percentage change= -10.2, 95% CI= -12.6, -7.8), and 25-29 years (average annual percentage change= -2.6, 95% CI= -3.9, -1.2). Trends from 2008 to 2018 were stable for older age groups (30-34 and 35-39 years). Results show reductions in high-grade cervical lesion incidence among ages most likely to have benefited from the human papillomavirus vaccine. Declines among young, screened women suggest causes other than reduction in screening. Evidence of vaccine impact in populations with low-vaccination coverage, such as Tennessee, is promising.

Epidemiological profile of american tegumentary leishmaniasis in the state of Maranhão in recent years

American Tegumentary Leishmaniasis (ATL) is a non-contagious disease, caused by a protozoan of the genus Leishmania, vector-borne by sandflies. Initially it is enzootic, but it can affect humans in a secondary way, characterizing itself as a zoonosis. It has great epidemiological importance due to the complexity of the treatment. The disease has been spreading on a large scale throughout Brazil, as well as in the state of Maranhão. This study is a descriptive approach with the use of confirmed cases of ATL by the Department of Informatics of the Unified Health System, for the years 2010 to 2019 for the state of Maranhão. The following variables were analyzed: annual notifications, gender, age group, clinical forms, case outcome and municipalities with the most notifications. During the study period, 19,043 cases were confirmed in the state. The year 2011 had the highest number of notifications, with 2,948 cases and an incidence of 44.83 cases per 100,000 inhabitants. The male gender was the most affected with 71.9%. The predominant age group was between 20 and 39 years old, with 42.7%. The cutaneous form was prevalent with 96.4%. The three municipalities with the highest number of records were Montes Altos (West Mesoregion), Buriticupu (West Mesoregion) and Arame (Centro Maranhense Mesoregion). The state of Maranhão is considered endemic for ATL, so it is considered essential to continuously adopt measures to combat the vector and to conduct educational campaigns that inform the population about minimizing the possibilities of disease transmission.

How Relative Age Effects Associate with Football Players' Market Values: Indicators of Losing Talent and Wasting Money.

Background: In football, annual age-group categorization leads to relative age effects (RAEs) in talent development. Given such trends, relative age may also associate with market values. This study analyzed the relationship between RAEs and market values of youth players. Methods: Age category, birthdate, and market values of 11,738 youth male football players were obtained from the “transfermarkt.de” database, which delivers a good proxy for real market values. RAEs were calculated using odds ratios (OR) with 95% confidence intervals (95%CI). Results: Significant RAEs were found across all age-groups (p < 0.05). The largest RAEs occurred in U18 players (Q1 [relatively older] v Q4 [relatively younger] OR = 3.1) ORs decreased with age category, i.e., U19 (2.7), U20 (2.6), U21 (2.4), U22 (2.2), and U23 (1.8). At U19s, Q1 players were associated with significantly higher market values than Q4 players. However, by U21, U22, and U23 RAEs were inversed, with correspondingly higher market values for Q4 players apparent. While large typical RAEs for all playing positions was observed in younger age categories (U18–U20), inversed RAEs were only evident for defenders (small-medium) and for strikers (medium-large) in U21–U23 (not goalkeepers and midfielders). Conclusions: Assuming an equal distribution of football talent exists across annual cohorts, results indicate the selection and market value of young professional players is dynamic. Findings suggest a potential biased selection, and undervaluing of Q4 players in younger age groups, as their representation and market value increased over time. By contrast, the changing representations and market values of Q1 players suggest initial overvaluing in performance and monetary terms. Therefore, this inefficient talent selection and the accompanying waste of money should be improved.

The relative age effect is more than just participation bias in badminton

Background: Annual age grouping is a widely used strategy to allocate players to age categories for more equal and fair opportunities considering the developmental differences. Although it is a well-intended strategy, certain (dis)advantages occur because of the subtle age-related differences within the same age groups. Objective: The purpose of the current study was to investigate the relative age effect among badminton players reaching the podium in the last three consecutive European U15, U17 and Junior (U19) Badminton Championships. Methods: A total of 288 medal owners from 20 countries were evaluated in the study. Chi-square (χ2) goodness-of-fit tests were used to compare the obtained birth month distributions across the quartiles (Q), and odds ratios and 95% confidence intervals were calculated in order to compare quartiles with each other. Results: Statistically significant relative age effects were determined favouring relatively older athletes in the total sample (χ2 = 82.278, p < .001). Statistically significant distribution differences were noted in both singles and doubles categories in total (χ2 = 18.778, p < .001; χ2 = 63.815, p < .001, respectively). Striking findings were determined in Q1-Q4 and Q2-Q4 comparisons as players in Q1 and Q2 were more than five and four times as likely to reach the podium than players in Q4, respectively. Conclusions: Results of this study confirm the presence of relative age effect among award-winning badminton players which goes beyond the classical participation trends findings, and stress the importance of the issue for talent development, selection and success.

"Birthday-Banding" as a Strategy to Moderate the Relative Age Effect: A Case Study Into the England Squash Talent Pathway.

The relative age effect (RAE) is almost pervasive throughout youth sports, whereby relatively older athletes are consistently overrepresented compared to their relatively younger peers. Although researchers regularly cite the need for sports programs to incorporate strategies to moderate the RAE, organizational structures often continue to adopt a one-dimensional (bi)annual-age group approach. In an effort to combat this issue, England Squash implemented a “birthday-banding” strategy in its talent pathway, whereby young athletes move up to their next age group on their birthday, with the aim to remove particular selection time points and fixed chronological bandings. Thus, the purpose of this study was to examine the potential effects of the birthday-banding strategy on birth quarter (BQ) distributions throughout the England Squash talent pathway. Three mixed-gender groups were populated and analyzed: (a) ASPIRE athletes (n = 250), (b) Development and Potential athletes (n = 52), and (c) Senior team and Academy athletes (n = 26). Chi-square analysis and odds ratios were used to test BQ distributions against national norms and between quartiles, respectively. Results reveal no significant difference between BQ distributions within all three groups (P > 0.05). In contrast to most studies examining the RAE within athlete development settings, there appears to be no RAE throughout the England Squash talent pathway. These findings suggest that the birthday-banding strategy may be a useful tool to moderate RAE in youth sports.

Campylobacteriosis in the Nordic countries from 2000 to 2015: Trends in time and space.

Aims: This study aimed to describe the demographic and geographic patterns of campylobacteriosis in Denmark, Finland, Norway and Sweden during 2000-2015. Methods: All Campylobacter infections notified to national authorities in the four countries during the study period were included. Background data for each notification consisted of patient age, sex, geographical location, presumed origin of infection and date of sample taken or date of sample received in the laboratory. These data were analysed in order to investigate annual trends, age group and sex patterns, as well as variations in the geographical and seasonal distribution of infections. Results: During the study period, a total of 164,001 Campylobacter infections, excluding travel-related cases, were registered, representing a mean annual incidence of 42.3 cases/100,000 population (ranging from 28.5 in Norway to 60.4 in Denmark). The incidence increased significantly from 2004 onwards in all countries, apart from Denmark. Males had higher infection rates in general. The highest incidences were observed in 0-4 year olds and those aged 20-29 years, apart from in Finland where there was no peak of infections in children aged 0-4 years. Seasonality of disease was distinct in all four countries, showing peaks of infection between July and August. In Sweden and Norway, incidences of campylobacteriosis were significantly higher in municipalities with high degrees of coastline or inland water. Conclusions: Campylobacter in the Nordic countries mostly follows known patterns with respect to demography and seasonality. Our study demonstrates new insights concerning geographical patterns of disease, highlighting possible future vulnerable population groups and locations.

Relative Age Effect in Physical Fitness Among Elementary and Junior High School Students.

The present study investigated characteristics of the relative age effect (RAE) among a general sample of Japanese elementary and junior high school students. Japan applies a unique annual age-grouping by birthdates between April 1 and March 31 of the following year for sport and education. Anthropometric and physical fitness data were obtained from 3,610 Japanese students, including height, weight, the 50-m sprint, standing long jump, grip strength, bent-leg sit-ups, sit and reach, side steps, 20-m shuttle run, and ball throw. We examined RAE-related differences in these data using a one-way analysis of variance by comparing students with birthdates in the first (April-September) versus second (October-March of the following year) semesters. We observed a significant RAE for boys aged 7 to 15 years on both anthropometric and fitness data, but a significant RAE for girls was only evident for physical fitness tests among elementary school and not junior high school students. Thus, a significant RAE in anthropometry and physical fitness was evident in a general sample of school children, and there were RAE gender differences among adolescents.

Relative age effects on motor performance of seventh-grade pupils

Annual age grouping of children according to their birth year is a common practice of the educational systems of many countries. This variation in birth dates among children grouped in the same generation is known as relative age and its implications on different developmental outcomes are referred to as relative age effects (RAEs). The previous body of research of RAEs in youth populations has focused on sporting samples; however, studies examining RAEs in physical education are scarce. The current study investigates the influence of the RAEs on motor abilities in a sample of adolescent pupils. The results indicate significant differences in motor abilities between relatively older and relatively younger participants of both sexes. Since RAE is an under-researched area in physical education, the results may have substantial implications for PE assessment given the fact that many PE teachers still carry out typical norm-referenced assessments. Possible recommendations for future research are discussed.

Falling status epilepticus mortality rates in England and Wales: 2001-2013?

Status epilepticus (SE) is associated with significant mortality and accounts for ~10% of epilepsy-related deaths. Epilepsy and SE mortality data from 2001 to 2013, in addition to annual age group populations for England and Wales, were obtained from the Office of National Statistics website (www.ons.gov.uk). Age-adjusted mortality rates for epilepsy and SE with 95% confidence intervals (CIs) were calculated using the European Standard Population. Trends in mortality rates for both epilepsy and SE were investigated using the Spearman coefficient. The crude mean epilepsy mortality rate per 100,000 person-years between 2001 and 2013 was 1.87 (95% CI 1.83-1.91), with a corresponding SE mortality rate of 0.14 (95% CI 0.13-0.15). The mean age-adjusted epilepsy mortality rate per 100,000 person years was 3.24 (95% CI 3.12-3.35), with a corresponding SE mortality rate of 0.24 (95% CI 0.21-0.27). All epilepsy deaths significantly decreased from 2001 to 2013 (Spearman's ρ -0.733, p = 0.004); this decrease was predominantly due to a decrease in SE deaths (Spearman's ρ -0.917, p < 0.001). In summary, our finding supports the hypothesis that the policy of early and aggressive treatment of SE may be improving the prognosis of this condition in England and Wales.

Anthropometric, speed and endurance characteristics of English academy soccer players: Do they influence obtaining a professional contract at 18 years of age?

This study evaluated the anthropometric, speed and endurance characteristics of English academy soccer players, comparing players who obtained a ‘professional’ contract at 18 years old with those that did not (‘academy’); 443 male academy soccer players from an English professional club undertook anthropometric (height and body mass), speed (10 and 20 m sprint) and endurance (Yo-Yo intermittent endurance test level 2 [Yo-Yo]) assessments between 2005 and 2012. Significant improvements with age were found for speed and endurance at each annual age group up until U18 age category. Significant differences were only observed between ‘professional’ and ‘academy’ players for 10 m ( p = 0.003, η2 = 0.01) and 20 m ( p = 0.001, η2 = 0.01) speed at U16 and U18 and Yo-Yo performance ( p = 0.001, η2 = 0.12) at U18 age category. Practitioners should use speed and endurance assessments for monitoring physical development of players rather than for talent identification purposes.

Relative age effects in athletic sprinting and corrective adjustments as a solution for their removal.

Relative Age Effects (RAEs) refer to the selection and performance differentials between children and youth who are categorized in annual-age groups. In the context of Swiss 60m athletic sprinting, 7761 male athletes aged 8 – 15 years were analysed, with this study examining whether: (i) RAE prevalence changed across annual age groups and according to performance level (i.e., all athletes, Top 50%, 25% & 10%); (ii) whether the relationship between relative age and performance could be quantified, and corrective adjustments applied to test if RAEs could be removed. Part one identified that when all athletes were included, typical RAEs were evident, with smaller comparative effect sizes, and progressively reduced with older age groups. However, RAE effect sizes increased linearly according to performance level (i.e., all athletes – Top 10%) regardless of age group. In part two, all athletes born in each quartile, and within each annual age group, were entered into linear regression analyses. Results identified that an almost one year relative age difference resulted in mean expected performance differences of 10.1% at age 8, 8.4% at 9, 6.8% at 10, 6.4% at 11, 6.0% at 12, 6.3% at 13, 6.7% at 14, and 5.3% at 15. Correction adjustments were then calculated according to day, month, quarter, and year, and used to demonstrate that RAEs can be effectively removed from all performance levels, and from Swiss junior sprinting more broadly. Such procedures could hold significant implications for sport participation as well as for performance assessment, evaluation, and selection during athlete development.

Monitoring anthropometry and fitness using maturity groups within youth rugby league.

-The purpose of this study was to evaluate the anthropometry and fitness, and change in these characteristics over time, of youth rugby league players by using maturity status to determine annual categories instead of traditional chronological annual-age grouping. One hundred and twenty-one male rugby league players were assessed using anthropometric (i.e., height, sitting height, body mass, and sum of 4 skinfolds) and fitness (i.e., vertical jump, medicine ball chest throw, 10- and 20-m sprint, and multistage fitness test [MSFT]) measures over a 5-year period. Each player was classified into 1 of 6 maturity groups based on their maturity offset (years from peak height velocity, i.e., 1.5 YPHV). Multivariate analysis of variance analyses identified significant (p < 0.001) main effects for maturity group for cross-sectional characteristics and longitudinal change in performance over time. Analyses demonstrated that more mature groups had greater anthropometric and fitness characteristics, except for endurance performance (MSFT: -2.5 YPHV = 1,872 ± 18 m vs. 2.5 YPHV = 1,675 ± 275 m). For longitudinal changes in characteristics over time, a significant effect was only identified for height and sitting height (p ≤ 0.05). These findings provide comparative data for anthropometric and fitness characteristics and change in performance over time in accordance with the maturity status within youth rugby league players. Classifying players into annual maturity groups may be an additional or alternative assessment method for evaluating anthropometry and fitness performance in adolescent populations. Furthermore, tracking performance changes over time, especially in relation to maturation, may reduce the limitations associated with chronological annual-age grouping.

Analysis of age–period–cohort effects on overall mortality in Andalusia (Southern Spain)

ObjectivesTo evaluate the age–period–cohort effects on overall mortality in Andalusia (Spain). Study designAn ecological study was implemented with a Lexis diagram triangle comprising each annual age group, year of death and year of birth as the unit of analysis. MethodsIn all 1,384,899 deaths from all causes were analysed for individuals between the ages of 1 and 84 years who died in Andalusia in the period 1981–2008. A non-linear regression model was estimated for each gender group and geographical area. The effects of age, year of death and birth cohort were parameterized using B-spline smoothing functions. ResultsThere is a downward trend in mortality by age to around the age of 15 years, from which point the trend turned upwards. For cohorts born between 1945 and 1965, the rate climbed steadily. From 1965, the rate turned downwards. Death rates increased between 1995 and 2000, only to turn down again until the end of the period. Broadly, these results were similar for both men and women, in all the provinces of Andalusia and for Andalusia as a whole. ConclusionsThis study points to an age–period–cohort effect on deaths from all causes in all the geographic areas studied.