title: Review of criterion-referenced standards for cardiorespiratory fitness: what percentage of 1 142 026 international children and youth are apparently healthy?
abstract: OBJECTIVE
  To identify criterion-referenced standards for cardiorespiratory fitness (CRF); to estimate the percentage of children and youth that met each standard; and to discuss strategies to help improve the utility of criterion-referenced standards for population health research.
  
  
  METHODS
  A search of four databases was undertaken to identify papers that reported criterion-referenced CRF standards for children and youth generated using the receiver operating characteristic curve technique. A pseudo-dataset representing the 20-m shuttle run test performance of 1 142 026 children and youth aged 9-17 years from 50 countries was generated using Monte Carlo simulation. Pseudo-data were used to estimate the international percentage of children and youth that met published criterion-referenced standards for CRF.
  
  
  RESULTS
  Ten studies reported criterion-referenced standards for healthy CRF in children and youth. The mean percentage (±95% CI) of children and youth that met the standards varied substantially across age groups from 36%±13% to 95%±4% among girls, and from 51%±7% to 96%±16% among boys. There was an age gradient across all criterion-referenced standards where younger children were more likely to meet the standards compared with older children, regardless of sex. Within age groups, mean percentages were more precise (smaller CI) for younger girls and older boys.
  
  
  CONCLUSIONS
  There are several CRF criterion-referenced standards for children and youth producing widely varying results. This study encourages using the interim international criterion-referenced standards of 35 and 42 mL/kg/min for girls and boys, respectively, to identify children and youth at risk of poor health-raising a clinical red flag.
authors.affiliation: Healthy Active Living and Obesity (HALO) Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada.
authors.forename: Justin J
authors.initials: JJ
authors.lastname: Lang
authors.affiliation: Healthy Active Living and Obesity (HALO) Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Tremblay
authors.affiliation: PROmoting FITness and Health through physical activity research group (PROFITH), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.|Karolinska Institutet, Huddinge, Sweden.
authors.forename: Francisco B
authors.initials: FB
authors.lastname: Ortega
authors.affiliation: PROmoting FITness and Health through physical activity research group (PROFITH), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.|Karolinska Institutet, Huddinge, Sweden.
authors.forename: Jonatan R
authors.initials: JR
authors.lastname: Ruiz
authors.affiliation: Department of Kinesiology and Public Health Education, University of North Dakota, Grand Forks, North Dakota, USA.|Alliance for Research in Exercise, Nutrition and Activity (ARENA), School of Health Sciences & Sansom Institute for Health Research, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Grant R
authors.initials: GR
authors.lastname: Tomkinson
mesh_terms: D000293:Adolescent; D000072599:Cardiorespiratory Fitness; D002648:Child; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D012372:ROC Curve; D012015:Reference Standards
keywords: 20-m shuttle run; cardiorespiratory fitness; children and youth; course navette; multinational