title: A Diagnostic Marker to Discriminate Childhood Apraxia of Speech From Speech Delay: II. Validity Studies of the Pause Marker.
abstract: The purpose of this 2nd article in this supplement is to report validity support findings for the Pause Marker (PM), a proposed single-sign diagnostic marker of childhood apraxia of speech (CAS).
  
  
  
  PM scores and additional perceptual and acoustic measures were obtained from 296 participants in cohorts with idiopathic and neurogenetic CAS, adult-onset apraxia of speech and primary progressive apraxia of speech, and idiopathic speech delay.
  
  
  
  Adjusted for questionable specificity disagreements with a pediatric Mayo Clinic diagnostic standard, the estimated sensitivity and specificity, respectively, of the PM were 86.8% and 100% for the CAS cohort, yielding positive and negative likelihood ratios of 56.45 (95% confidence interval [CI]: [1.15, 2763.31]) and 0.13 (95% CI [0.06, 0.30]). Specificity of the PM for 4 cohorts totaling 205 participants with speech delay was 98.5%.
  
  
  
  These findings are interpreted as providing support for the PM as a near-conclusive diagnostic marker of CAS.
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Lawrence D
authors.initials: LD
authors.lastname: Shriberg
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN.
authors.forename: Edythe A
authors.initials: EA
authors.lastname: Strand
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Marios
authors.initials: M
authors.lastname: Fourakis
authors.affiliation: Department of Communication Sciences and Disorders, Augustana College, Rock Island, IL.
authors.forename: Kathy J
authors.initials: KJ
authors.lastname: Jakielski
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Sheryl D
authors.initials: SD
authors.lastname: Hall
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Heather B
authors.initials: HB
authors.lastname: Karlsson
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Heather L
authors.initials: HL
authors.lastname: Mabie
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Jane L
authors.initials: JL
authors.lastname: McSweeny
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: Christie M
authors.initials: CM
authors.lastname: Tilkens
authors.affiliation: Waisman Center, University of Wisconsin-Madison.
authors.forename: David L
authors.initials: DL
authors.lastname: Wilson
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001072:Apraxias / Q000145:classification / Q000175:diagnosis* / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007805:Language Development Disorders / Q000145:classification / Q000175:diagnosis*; D007807:Language Tests; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013061:Speech Acoustics; D013062:Speech Articulation Tests; D055815:Young Adult