title: Hospital for Special Surgery Pediatric Functional Activity Brief Scale predicts physical fitness testing performance.
abstract: BACKGROUND
  An eight-item activity scale was recently developed and validated for use as a prognostic tool in clinical research in children and adolescents. It is unclear, however, if this brief questionnaire is predictive of quantitative metrics of physical activity and fitness.
  
  
  OBJECTIVE
  The purposes of this study were to prospectively administer the Hospital for Special Surgery Pediatric Functional Activity Brief Scale to a large cohort of healthy adolescents to determine (1) if the activity scale exhibits any floor or ceiling effects; (2) if scores on the activity scale are correlated with standardized physical fitness metrics; and if so, (3) to determine the discrimination ability of the activity scale to differentiate between adolescents with healthy or unhealthy levels of aerobic capacity and calculate an appropriate cutoff value for its use as a screening tool.
  
  
  METHODS
  One hundred eighty-two adolescents (mean, 15.3 years old) prospectively completed the activity scale and four standardized metrics of physical fitness: pushups, sit-ups, shuttle run exercise (Progressive Aerobic Cardiovascular Endurance Run), and calculated VO2-max. Age, sex, and body mass index were also recorded. Pearson correlations, regression analyses, and receiver operating characteristic analyses were used to evaluate activity scale performance.
  
  
  RESULTS
  The activity scale did not exhibit any floor or ceiling effects. Pushups (ρ = 0.28), sit-ups (ρ = 0.23), performance on the Progressive Aerobic Cardiovascular Endurance Run (ρ = 0.44), and VO2-max (ρ = 0.43) were all positively correlated with the activity scale score (Pearson correlations, all p < 0.001). Receiver operating characteristic analysis revealed that those with an activity score of ≤ 14 were at higher risk of having low levels of aerobic capacity.
  
  
  CONCLUSIONS
  In the current study, activity score was free of floor and ceiling effects and predictive of all four physical fitness metrics. An activity score of ≤ 14 was associated with at-risk aerobic capacity previously shown to be associated with an increased risk of metabolic syndrome. This study is the first to prospectively validate an activity questionnaire against quantitative physical fitness assessments and provides further evidence substantiating its use in outcomes research and screening for healthy levels of childhood activity and fitness.
  
  
  METHODS
  Level I, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Division of Pediatric Orthopaedic Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA, fabricantp@hss.edu.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Fabricant
authors.forename: Alex
authors.initials: A
authors.lastname: Robles
authors.forename: Son H
authors.initials: SH
authors.lastname: McLaren
authors.forename: Robert G
authors.initials: RG
authors.lastname: Marx
authors.forename: Roger F
authors.initials: RF
authors.lastname: Widmann
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Green
mesh_terms: D000293:Adolescent; D000367:Age Factors; D003430:Cross-Sectional Studies; D005080:Exercise Test; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D024821:Metabolic Syndrome / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D009043:Motor Activity; D010809:Physical Fitness; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012307:Risk Factors; D011795:Surveys and Questionnaires