title: Validity and reliability of the N-PASS assessment tool with acute pain.
abstract: OBJECTIVE
  To establish evidence of clinical validity and reliability of the Neonatal Pain, Agitation, and Sedation Scale (N-PASS) in neonates with acute heelstick pain.
  
  
  METHODS
  Prospective psychometric evaluation, randomized crossover design. Two nurses administered the N-PASS simultaneously and independently during an actual and sham heelstick done in randomized order. One nurse also administered the Premature Infant Pain Profile (PIPP) concurrently with the N-PASS. Heelsticks were videotaped for repeat analysis.
  
  
  RESULTS
  Construct (discriminate) validity was established through the Wilcoxon Signed-ranks test, comparing the distribution of the heelstick and sham N-PASS scores. The mean pain scores were 3.93 (2.30) and 0.81 (1.21) for the heelstick and sham procedures, respectively (Z=-6.429, P<0.0001). Convergent validity was demonstrated by correlation with the PIPP scores (Spearman rank correlation coefficient of 0.75 and 0.72 for raters 1 and 2, respectively). Inter-rater reliability was high, measured by intra-class coefficients; the ICC estimates (95% CI) of the pain scale were 0.86 (0.78, 0.92) and 0.93 (0.88, 0.96) for a single rating and average of two independent ratings, respectively (P<0.0001). Internal consistency, measured by Cronbach's alpha, was evident (0.84 to 0.89). Test-retest reliability was demonstrated by repeat scoring of videotaped heelsticks, measured by Spearman's rho correlation (0.874, P<0.0001).
  
  
  CONCLUSIONS
  This research provides beginning evidence that the N-PASS is a valid and reliable tool for assessing acute heelstick pain in infants 0 to 30 days of age, 23 to 40 weeks gestation.
authors.affiliation: Department of Neonatology and Pediatrics, Gloria Smith/American Nurses Foundation Scholar, Loyola University Medical Center, Maywood, IL 60153, USA. phummel@lumc.edu
authors.forename: P
authors.initials: P
authors.lastname: Hummel
authors.forename: P
authors.initials: P
authors.lastname: Lawlor-Klean
authors.forename: M G
authors.initials: MG
authors.lastname: Weiss
mesh_terms: D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010146:Pain; D010147:Pain Measurement / Q000379:methods*; D015203:Reproducibility of Results