title: Reliability and predictors of resistive load detection in children with persistent asthma: a multivariate approach.
abstract: OBJECTIVE
  Resistive load detection tasks enable analysis of individual differences in psychophysical outcomes. The purpose of this study was to determine both the reliability and predictors of resistive load detection in children with persistent asthma who completed multiple testing sessions.
  
  
  METHODS
  Both University of North Carolina (UNC) Charlotte and Ohio University institutional review boards approved the research protocol. The detection of inspiratory resistive loads was evaluated in 75 children with asthma between 8 and 15 years of age. Each child participated in four experimental sessions that occurred approximately once every 2 weeks. Multivariate analyses were used to delineate predictors of task performance.
  
  
  RESULTS
  Reliability of resistive load detection was determined for each child, and predictors of load detection outcomes were investigated in two groups of children: those who performed reliably in all four sessions (n = 31) and those who performed reliably in three or fewer sessions (n = 44). Three factors (development, symptoms, and compliance) accounted for 66.3% of the variance among variables that predicted 38.7% of the variance in load detection outcomes (Multiple R = 0.62, p = 0.004) and correctly classified performance as reliable or less reliable in 80.6% of the children, χ(2)(12) = 28.88, p = 0.004.
  
  
  CONCLUSIONS
  Cognitive and physical development, appraisal of symptom experiences, and adherence-related behaviors (1) account for a significant proportion of the interrelationships among variables that affect perception of airflow obstruction in children with asthma and (2) differentiate between children who perform more or less reliably in a resistive load detection task.
authors.affiliation: Department of Public Health Sciences, University of North Carolina Charlotte , Charlotte, NC , USA .
authors.forename: Andrew
authors.initials: A
authors.lastname: Harver
authors.forename: Allison
authors.initials: A
authors.lastname: Dyer
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Ersek
authors.forename: Harry
authors.initials: H
authors.lastname: Kotses
authors.forename: C Thomas
authors.initials: CT
authors.lastname: Humphries
mesh_terms: D000293:Adolescent; D041923:Adolescent Development; D000403:Airway Resistance; D001249:Asthma / Q000175:diagnosis* / Q000523:psychology*; D002648:Child; D002657:Child Development; D005260:Female; D005540:Forced Expiratory Flow Rates; D006801:Humans; D008297:Male; D009820:Ohio; D010349:Patient Compliance / Q000523:psychology; D010465:Perception; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012959:Socioeconomic Factors
keywords: Asthma; children; discriminant analysis; factor analysis; resistive loads; threshold resistance to breathing