Markers, models, and measurement error:

85
Markers, models, and measurement error: Exploring the Links Between Attention Deficits and Language Impairments [email protected] SRCLD 2014

description

Markers, models, and measurement error: . Exploring the Links Between Attention Deficits and Language Impairments . Acknowledgements. - PowerPoint PPT Presentation

Transcript of Markers, models, and measurement error:

Page 1: Markers, models, and measurement error:

Markers, models, and measurement error:

Exploring the Links Between Attention Deficits and Language Impairments

[email protected] SRCLD 2014

Page 2: Markers, models, and measurement error:

Acknowledgements

• Funding provided by: NIDCD grants R03DC008382 “Psycholinguistic and Socioemotional Profiling of SLI and ADHD” and R01DC011023 “Co-occurrence of Language and Attention Difficulties in Children”.

• Project Manager: Andrea Ash, PhD • Consultants: Sam Goldstein, PhD Neurology, Learning and Behavior Center, SLC

UT; Tiffany Hogan, PhD MGH Institute of Health Professions, Boston MA. • Community contacts: Lisa Holmstead (SLC School District), Rebecca Garda, Deb

Luker (Jordan School District), Linda Smith (CHADD), Carrie Francis (Boys and Girls Club)

• Research assistants: David Aamodt, Chelsea Ash, Lyndi Ballard, Peter Behnke, Hannah Caron, Kimber Campbell, Jessica Carrizo, Jamie Dressler, Olivia Erickson, Micah Foster, Kristin Hatch, Nathan Lily, Amy Ludlow, Kristi Moon, Elie Munyankindi, Britta Rajamaki, Michelle Stettler, Jennifer Thinnes Whittaker, McKenzie Rohde, Heather Thompson, and Melissa Whitchurch.

Page 3: Markers, models, and measurement error:

Disclosure Statement

I have no relevant relationships to disclose (financial or non-financial).

Page 4: Markers, models, and measurement error:

ADHD• “Household term”

• “developmentally inappropriate levels of inattention, hyperactivity, and impulsivity

• Prevalence: 3-6% (e.g. Willcutt, 2012)

• The most common pediatric psychiatric disorder

• Dx Rate: most recent CDC (2013) report = 11%; varies considerably by region

• M:F ratio = 4.0:1.0

SLI• “Researcher argot”

• “diminished language proficiencies in the absence of significant limitations in hearing acuity, cognitive development, or social development”

• Prevalence: 5-7% (e.g. Tomblin et al., 1997)

• The most common pediatric communication disorder

• Dx Rate: Unknown. Not tracked by CDC, USDOE, or ASHA - but probably considerably less than prevalence (Johnson et al., 1999; Zhang & Tomblin, 2000; Jones et al., 2014)

• M:F ratio = 1.6:1.0

Page 5: Markers, models, and measurement error:

ADHD cont’d• Standardized informant rating scales,

psychiatric interviews, EF/CPT tasks

• Highly comorbid condition (co-occurring anxiety, depression, externalizing disorders, reading disability)

• Heterogeneity has encouraged pursuit of various subtyping schemes that have yet to document developmental stability (e.g. Lahey et al., 2005)

• Research focus on establishing markers and procedures for differential diagnosis

• “Well-resourced” disability relative to prevalence rate (Bishop, 2010)

SLI cont’d• Standardized language tests, language

samples, verbal memory tasks

• Frequently co-occurs with reading disability; associations with socioemotional disorders mixed

• Heterogeneity has encouraged pursuit of various subtyping schemes that have yet to document developmental stability (e.g. Tomblin et al., 2003)

• Research focus on expanding phenotype to include non-linguistic symptoms associated with other disorders

• “Under-resourced” disability relative to prevalence rate (Bishop, 2010)

Page 6: Markers, models, and measurement error:

ADHD and LI • ADHD has also been one of the most frequently reported

co-occurring neurodevelopmental disorders in study samples of children with language impairments (LI) (e.g. Beitchman, Hood, & Inglis, 1990; Benasich, Curtiss, & Tallal, 1993; Lindsay, Dockrell, & Strand, 2007; St. Clair, Pickles, Durkin, & Conti-Ramsden, 2011; Willinger et al., 2003)….

•…although the literature provides some discrepant findings with the extent to which co-occurrence rates have exceeded expectations based on general population estimates (cf. Lindsay & Dockrell, 2008; Redmond & Rice, 2002; Rescorla, Ross, & McClure, 2007; Whitehouse, Robinson, & Zubrick, 2011).

Page 7: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

Page 8: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al.(2012)

ADHD diagnosis rate: both sexesCDC (2013)

Page 9: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

ADHD Dx rate: both sexesCDC (2013) ADHD Dx rate:

malesCDC (2013)

Page 10: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

ADHD Dx rate: both sexesCDC (2013)

ADHD Dx rate: malesCDC (2013)

ADHD Dx rate also varies as a function of locale: western states below 6%; southern/eastern states above 10%

Page 11: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

ADHD Dx rate: both sexesCDC (2013)

ADHD Dx rate: malesCDC (2013)

LI/SLI prevalence rate:Johnson et al., (1999); Tomblin et al., (1997)

Page 12: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

ADHD Dx rate: both sexesCDC (2013)

ADHD Dx rate: malesCDC (2013)

LI/SLI prevalence rate:Johnson et al., (1999); Tomblin et al., (1997) LI/SLI Dx

rate: ?Ironically, ASHA has tracked service provision for cases of ADHD but hasn’t collected a census on the cases of primary LI/SLI served by SLPs

Page 13: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

ADHD Dx rate: both sexesCDC (2013)

ADHD Dx rate: malesCDC (2013)

LI/SLI prevalence rate:Johnson et al., (1999); Tomblin et al., (1997)

ADHD+LI CO-OCCURRENCE Lindsay & Dockrell (2008);Snowling et al. (2006)

Gualiteri et al.(1983)

Page 14: Markers, models, and measurement error:

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

ADHD prevalence rate:APA (2013); Willcutt et al. (2012)

LI/SLI prevalence rate:Johnson et al., (1999); Tomblin et al., (1997)

ADHD+LI CO-OCCURRENCE Lindsay & Dockrell (2008);Snowling et al. (2006) Gualiteri et al.

(1983)

Warr-Leeper et al. (1994);Walsh et al. (2014)

Trautman et al. (1990)

Beitchman et al. (1989)

Tirosh & Cohen (1998); Love & Thompson (1988)Cohen et al. (1998)

Redmond & Rice (2002);Willinger et al. (2003) Tomblin et al.

(2000)Baker & Cantwell (1987); St. Clair et al. (2011)

ADHD Dx rate: malesCDC (2013)

ADHD Dx rate: both sexesCDC (2013)

Page 15: Markers, models, and measurement error:

POTENTIAL CONTRIBUTERS TO CROSS SIGNALS

• “Berkson’s bias”• Clinical: 3-90%; Epidemiological: 18-59%

• Primary recruitment: • LI cases: 3-59%; ADHD cases: 45-90%

• Older/newer reports:• Before 2000: 17-90%; After 2000: 3-73%

• Low nonverbal IQ:• Not controlled: 3-90%; Controlled: 3-33%

Page 16: Markers, models, and measurement error:

POTENTIAL CONTRIBUTERS TO CROSS SIGNALS, cont’d

• Measurement?• Co-occurrence estimates are meaningless if indices cannot be

trusted to differentiate between disorders.

• Some popular measures are incapable of differentiating typical from atypical status.

• Some measures are good with the typical vs. atypical distinction but are poor when used to differentiate among atypical designations.

Page 17: Markers, models, and measurement error:
Page 18: Markers, models, and measurement error:
Page 19: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis

• Vocabulary, verbal IQ, and pragmatic indices represent poor choices

• Many language tests cannot reliably differentiate cases of LI from non-LI; vocabulary metrics particularly weak (Spaulding, Plante, & Farinella, 2006).

• ADHD symptoms align with pragmatic deficits (Camarata, Hughes, & Ruhl, 1988).

• Fine (2006) “Language in Psychiatry”: semiotic/pragmatic framing of clinical features associated with ADHD, psychotic disorders, mood disorders, personality disorders, etc.

• Pragmatic symptoms load on to a common factor with psychiatric symptom scales and not on to a factor with other language measures (Ash & Redmond, 2014).

Page 20: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• Verbal memory (NWR, SR) and tense-marking indices represent good choices (Archibald & Joanisse 2009; Conti-Ramsden, Botting, & Faragher, 2001; SLI Consortium, 2002).

• Projects: 2 study samples

• Clinically sourced• Community sourced

Page 21: Markers, models, and measurement error:

I. Clinically sourced sample (n = 60, 7- 8-years) (Redmond, Thompson, & Goldstein, 2011)

• Ascertainment procedure:• SLP caseloads, clinical psychologist caseloads/CHADD, school flyers, community bulletins

• Eligibility Protocol: • Exclusionary = hearing screening, speech screening, nonverbal IQ < 80, autism,

monolingual status• 20 cases of SLI = Dx of LI, receipt of services, below cutoff on CELF4 screening test

(CELF4-ST)• 20 cases of ADHD = Dx of combined-type ADHD, receipt of services, above cutoff on

CBCL DSM-IV ADHD• 20 cases of TD = no services, above cutoff on CELF4-ST, below cutoff on CBCL DSM-IV

ADHD• ADHD+LI (8 supplemental cases) = met criteria for SLI and ADHD

Psycholinguistic Markers and Differential Diagnosis, cont’d

Page 22: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• Measures:• TEGI screening (past, present probes) (Rice & Wexler, 2001), Dollaghan

and Campbell’s (1998) NWR, Redmond’s (2005) sentence recall, and the Test of Narrative Language (Gillam & Pearson, 2004).

• Naglieri Nonverbal Achievement Test (Naglieri, 2003), My Life in School Checklist (Sharp et al., 1994), Feelings about School Survey (Valeski & Stipek, 2001), Test of Variables of Attention (Dupuy & Greenberg, 1993).

• Cases of ADHD tested “off medication”

Page 23: Markers, models, and measurement error:

Redmond, Thompson, & Goldstein (2011)

Page 24: Markers, models, and measurement error:

Redmond, Thompson, & Goldstein (2011)

Page 25: Markers, models, and measurement error:

Redmond, Thompson, & Goldstein (2011)

Page 26: Markers, models, and measurement error:

Narratives: Redmond, Thompson, & Goldstein (2011)

Page 27: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• Parigger (2012) “Language and Executive Functioning in Children with ADHD” • Replication and extension of Redmond, Thompson, & Goldstein

(2011) in a sample of Dutch-speaking children (SLI < ADHD =TD).

• n.s. associations between NWR, SR, Tense-Marking, Narratives (Frog Stories) and ADHD symptoms or EF measures within any of the groups (SLI, ADHD, TD).

• n.s. associations between CCC-2 and EF measures (contrary to predictions based on Tannock & Schachar, 1996).

Page 28: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

II. “Clinically enriched” community sourced sample (n = 122, grades 3 and 2 available).

• Ascertainment procedure• On site school screenings via 1,000+ recruitment flyers sent home.

• Targeting students in regular ed, CD, LD, EBD, resource/Tier 2 services (n = 420), using Redmond’s (2005) SR (cf. Archibald & Joanisse, 2009) and the Past Probe from the TEGI.

• Screener cutoffs determined using only regular ed students (cf. Pena, Spaulding, & Plante, 2006). • All positive screening cases (n = 71) and a comparison group of negative cases (n = 57) invited

to participate in blinded confirmatory testing using CELF4 (67% retention).

• Supplemental cases of known LI (n = 23) added from another school district.

Page 29: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• Eligibility Measures:• Exclusionary: ELL, “gifted/enriched learning programs”, speech screening, hearing

screening • 50 Confirmed LI = below -1.0 SD on CELF4

• SLI (70%), NLI, ADHD+LI, autism+LI, EBD+LI• 72 Confirmed Non-LI = above -1.0 on CELF4

• TD (75%), Low-Nonverbal, ADHD, autism, EBD, LD/RD, SWMI • Measures:

• CELF4, TEGI • My Life in School Checklist, Automated Working Memory Assessment (Alloway, 2007),

Children’s Communication Checklist-2 (Bishop, 2006), NWR

• Cases of ADHD tested “off medication”

Page 30: Markers, models, and measurement error:

 

Test Standard(CELF-4 < 85)

 

 

+ __  

 

Screener

(SR and PT < 15%ile OR SR/PT < 10%ile based on regular ed only norms)

 

47 

18

 

PPV = .723

 

 3

 54

 

NPV = .947

   Sensitivity

= .94Specificity

= .75

 

Page 31: Markers, models, and measurement error:

 

Test Standard(CELF-4 < 85)

 

 

+ __  

 

Screener

(SR and PT < 15%ile OR SR/PT < 10%ile based on regular ed only norms)

 

47 

18

 

PPV = .723

 

 3

 54

 

NPV = .947

   Sensitivity

= .94Specificity

= .75

 

Page 32: Markers, models, and measurement error:

11%

22%

11%

50%

6%

Screening False AlarmsADHD AWMA ReadingTD CCC2-Pragmatic

Page 33: Markers, models, and measurement error:

  SR PT CELF-4 TEGI

SR -- .539*** .846*** .702***

PT   -- .507*** .813**

CELF-4     -- .661***

TEGI       --

*p < .05, **p < .01, ***p <.001

Zero order Pearson product correlations among screening (SR, PT) and confirmatory measures (CELF-4, TEGI) N = 122

Page 34: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• Temporal stability associated with SR and PT screeners • 2-5 month gap between screenings and confirmatory testing• Data available for 102 participants • Different examiners (blinded)

• SR: r = .884, p <.001

• PT: r = .820, p <.001

Page 35: Markers, models, and measurement error:

Psycholinguistic Markers and Differential Diagnosis, cont’d

• A distinct communication profile for ADHD?

• ADHD status associated with elevated levels of vocal hyper-function in young males (loudness, speaking rate, excessive talking) and poor voice quality (hoarseness) relative to TD controls (Garcia-Real et al., 2013; Hamdan et al., 2009).

• ADHD > SLI mazes/utterance formulation problems in conversational

samples (Redmond, 2004).

Page 36: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis

• Behavioral/Neuropsychological indices: EF tasks represent poor choices• Stroop, Go/No-Go Tower of London/Hanoi, Wisconsin card sorting, Porteus mazes, etc. • Planning, response inhibition, attentional shift, vigilance, working memory, etc. • Meta-analyses: moderate effect sizes and lack of universality of EF deficits among ADHD (~50%) compromise

both positive and negative predictive powers (Willcutt et al., 2005; Nigg et al., 2005).

• Many “home-grown” versions of EF tasks in the literature with unknown levels of reliability and validity

• Test-retest reliability associated with standardized EF tasks often <.60

• EF tasks may be particularly problematic with LI cases:

• 81% false positive rate for GDS EF task against standard of parent/teacher rated ADHD [LI vs. ADHD+LI] (Rielly et al., 1999).

Page 37: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis, cont’d

• Behavioral/Neuropsychological indices: CPTs represent poor choices• X-type, AX-type, not-X type, XX-type, etc.• Omission errors, commission errors, sensitivity (d’), response bias (Beta), response time, etc.

• Riccio, Reynolds, & Lowe (2001) “Clinical Applications of Continuous Performance Tests”: • “….virtually any disorder of childhood that disrupts or compromises CNS integrity or function is a strong

candidate to produce decrements in CPT performance (p. 229)”

• Eg: mental retardation, TBI, affective disorders, sleep disorders, phenylketonuria, autism, schizophrenia, learning disabilities, Tourette’s syndrome, fetal toxic exposures, maltreatment, neurofibromatosis, low birth weight, conduct disorder, congenital heart defects, seizure disorders, hearing impairment, and general medical referrals…..

• ….and SLI (e.g. Finneran Francis, & Leonard, 2009; Spaulding, Plante, & Vance, 2008)

• “Reliance on CPTs as a primary diagnostic tool will result in an unacceptably high number of false positive errors (i.e. over-diagnosis of ADHD)” (pp. 232).

Page 38: Markers, models, and measurement error:

Test of Variables of Attention (TOVA)

 

 ADHD

(n =13/20)

 SLI

(n =17/20)

 TD

(n =18/20)

 F

 Contrasts

Percent omission errors 

 11.49

(10.11)0.62 to 25.93

 

 12.37

(13.01)0.31 to 36.11

 5.08

(5.02)0.31 to 20.06

 3.90*

 TD < ADHD, SLI

Percent commission errors 

10.00(7.08)

1.54 to 29.71 

8.72(4.79)

0.93 to 18.07

6.67(4.22)

0.93 to 17.59

1.57 ADHD, SLI, TD

Response time (msec)  

609.00(103.21)

447 to 788 

578.06(96.07)

436 to 819 

572.72(91.36)

374 to 790

0.59 ADHD, SLI, TD

Variability (SD, msec) 

240.92(56.84)

146 to 325 

220.18(50.66)

146 to 342 

202.22(43.14)

129 to 280

2.29 ADHD, SLI, TD

D-prime (hit rate/false alarm rate)

 

2.86(0.95)

1.26 to 4.52 

2.91(0.99)

1.10 to 5.10

3.44(0.68)

2.48 to 5.10

2.23 ADHD, SLI, TD

 * p <.05 

Some unpublishable data from the clinically sourced sample…

Page 39: Markers, models, and measurement error:

Test of Variables of Attention (TOVA)

 

 ADHD

(n =13/20)

 SLI

(n =17/20)

 TD

(n =18/20)

 F

 Contrasts

Percent omission errors 

 11.49

(10.11)0.62 to 25.93

 

 12.37

(13.01)0.31 to 36.11

 5.08

(5.02)0.31 to 20.06

 3.90*

 TD < ADHD, SLI

Percent commission errors 

10.00(7.08)

1.54 to 29.71 

8.72(4.79)

0.93 to 18.07

6.67(4.22)

0.93 to 17.59

1.57 ADHD, SLI, TD

Response time (msec)  

609.00(103.21)

447 to 788 

578.06(96.07)

436 to 819 

572.72(91.36)

374 to 790

0.59 ADHD, SLI, TD

Variability (SD, msec) 

240.92(56.84)

146 to 325 

220.18(50.66)

146 to 342 

202.22(43.14)

129 to 280

2.29 ADHD, SLI, TD

D-prime (hit rate/false alarm rate)

 

2.86(0.95)

1.26 to 4.52 

2.91(0.99)

1.10 to 5.10

3.44(0.68)

2.48 to 5.10

2.23 ADHD, SLI, TD

 * p <.05 

Some unpublishable data from the clinically sourced sample…

Page 40: Markers, models, and measurement error:
Page 41: Markers, models, and measurement error:
Page 42: Markers, models, and measurement error:
Page 43: Markers, models, and measurement error:
Page 44: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis, cont’d

• Standardized parent ratings preferred over teacher ratings • Parent ratings are sufficient – 90% agreement between parent and teacher assignment of ADHD

status if parent rating positive (Biederman et al, 1990).

• …..However, levels of overall agreement between parent and teacher ADHD ratings have consistently been modest (r < .50) (Barkley, 2006).

• Teacher ratings don’t agree with observational measures of ADHD symptoms (e.g. Schachar, Sandberg

& Rutter, 1986) or with each other (Barkley, 2006; Redmond & Rice, 2001)

• Heritability estimates of ADHD higher for parent ratings than teacher ratings (Merwood et al., 2013).

• Teacher ratings of ADHD symptoms may be particularly biased against students with LI relative to other clinical groups when compared against blinded psychiatric interviews -twice as many false positives as true positives: 20% vs. 10% (Charach et al., 2009).

Page 45: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis, cont’d

• DSM III: Presence of ADHD symptoms in either academic or non-academic settings- “situational ADHD”.

• DSM IV: “…at last some ADHD symptoms need to be present in multiple settings”

• DSM 5: “Children with specific learning disorder may appear inattentive because of frustration, lack of interest, or limited ability. However, inattention in individuals with a specific learning disorder who do not have ADHD is not impairing outside of academic work”

Page 46: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis, cont’d

• Parent ratings work best if adjusted for presence of language/academic items

• Redmond (2001): Language and academic items have often featured on socioemotional behavioral rating scales (e.g. “won’t talk” ,”speech problems”, “poor school work”, “difficulty doing or completing homework”, “does not seem to listen to what is being said to him/her”, “cannot grasp arithmetic”, “has sloppy handwriting”, and “spelling is poor”).

• Consequences of removing items on instrument validity?

• Removing overlapping symptoms from scales or requiring higher cutoffs for the purposes of differential diagnosis represents a common suggestion (e.g. Brock, Jimmerson, & Hansen, 2009; Millberger et al., 1995).

Page 47: Markers, models, and measurement error:

Socioemotional Behavioral Markers and Differential Diagnosis, cont’d• Redmond & Ash (2014)

• Language and academic items appear on several of the CBCL and the Conners’ syndrome scales • CBCL: Withdrawn, Social Problems, Attention Problems, Internalizing• Conners’: Cognitive Problems/Inattention, DSM-Inattentive, DSM-Total

• Removing items from these scales improved accuracy of differentiation between SLI and ADHD without compromising differentiation between ADHD and TD (clinical sourced sample)

• ADHD vs. SLI differentiation improved with slightly higher cutoffs

• Best ADHD vs. SLI differentiation achieved on Conners’ DSM-hyperactive and DSM-impulsive scales (ROC areas: .929 -.971).

Page 48: Markers, models, and measurement error:
Page 49: Markers, models, and measurement error:

The Impact of Comorbidity on LI

• Multiple co-occurring disorders might produce additive/interactive effects on clinical symptoms (cf. Wachs, 2000)….• NLI worse than SLI across various language metrics (Wetherell et al., 2007; Fey et al., 2004;

Nippold et al., 2008; Pearce et al., 2010 Rice et al., 2004)• NLI associated with greater risk for behavior problems (Beitchman et al., 1989; Elbro et al.,

2011; Law et al., 2009; Snowling et al., 2006). • …. Or not

• SLI = SLI+RD across various language metrics (Bishop et al., 2009; Catts et al., 2005).

• Co-occurring disorders can also be associated with subtractive effects if protective factors associated with one of the disorders offsets risk factors associated with the other

Page 50: Markers, models, and measurement error:

   SLI

(n =19)

 ADHD+LI(n =19)

 TD

(n =19)

 F

(2,54)

 Partial η2

 Contrasts

M (SD)

Range M (SD)

Range M (SD)

Range      

                   1.Nonword Rep. 79.1

(9.2)54.2-90 81.1

(8.6)66-97.9 89.6

(6.7)69.8-97.9 8.71** .244 SLI = ADHD+LI <

TD2. Sentence Recall

11.7(6.9)

0-26 14.7(7.3)

1-27 24.4(4.1)

15-31 21.3*** .441 SLI = ADHD+LI < TD

3. TEGI                  3rd person present 84.9

(24.1)0-100 91.0

(16.1)33-100 99.4

(2.5)89-100 3.6* .117 SLI = ADHD+LI <

TDRegular past 77.4

(29.7)0-100 84.63

(16.8)40-100 97.0

(4.7)90-100 4.7* .147 SLI = ADHD+LI <

TDIrregular finite 79.4

(27.4)0-100 89.53

(14.5)63-100 99.4

(2.8)88-100 5.9** .179 SLI = ADHD+LI <

TDIrregular correct 49.5

(19.7)0-75 42.9

(28.4)0-100 83.9

(23.3)25-100 15.9*** .370 SLI = ADHD+LI <

TD                   

* p < .05, ** p <.01, *** p <.001

Combined clinical and community samples (n = 57, 7- 9-years): Redmond, Ash, & Hogan (under review)

Page 51: Markers, models, and measurement error:

   SLI

(n =19)

 ADHD+LI(n =19)

 TD

(n =19)

 F

(2,54)

 Partial η2

 Contrasts

M (SD)

Range M (SD)

Range M (SD)

Range      

                   1.Nonword Rep. 79.1

(9.2)54.2-90 81.1

(8.6)66-97.9 89.6

(6.7)69.8-97.9 8.71** .244 SLI = ADHD+LI <

TD2. Sentence Recall

11.7(6.9)

0-26 14.7(7.3)

1-27 24.4(4.1)

15-31 21.3*** .441 SLI = ADHD+LI < TD

3. TEGI                  3rd person present 84.9

(24.1)0-100 91.0

(16.1)33-100 99.4

(2.5)89-100 3.6* .117 SLI = ADHD+LI <

TDRegular past 77.4

(29.7)0-100 84.63

(16.8)40-100 97.0

(4.7)90-100 4.7* .147 SLI = ADHD+LI <

TDIrregular finite 79.4

(27.4)0-100 89.53

(14.5)63-100 99.4

(2.8)88-100 5.9** .179 SLI = ADHD+LI <

TDIrregular correct 49.5

(19.7)0-75 42.9

(28.4)0-100 83.9

(23.3)25-100 15.9*** .370 SLI = ADHD+LI <

TD                   

* p < .05, ** p <.01, *** p <.001

Combined clinical and community samples (n = 57, 7- 9-years): Redmond, Ash, & Hogan (under review)

Page 52: Markers, models, and measurement error:

   SLI

(n =19)

 ADHD+LI(n =19)

 TD

(n =19)

 F

(2,54)

 Partial η2

 Contrasts

M (SD)

Range M (SD)

Range M (SD)

Range      

                   1.Nonword Rep. 79.1

(9.2)54.2-90 81.1

(8.6)66-97.9 89.6

(6.7)69.8-97.9 8.71** .244 SLI = ADHD+LI <

TD2. Sentence Recall

11.7(6.9)

0-26 14.7(7.3)

1-27 24.4(4.1)

15-31 21.3*** .441 SLI = ADHD+LI < TD

3. TEGI                  3rd person present 84.9

(24.1)0-100 91.0

(16.1)33-100 99.4

(2.5)89-100 3.6* .117 SLI = ADHD+LI <

TDRegular past 77.4

(29.7)0-100 84.63

(16.8)40-100 97.0

(4.7)90-100 4.7* .147 SLI = ADHD+LI <

TDIrregular finite 79.4

(27.4)0-100 89.53

(14.5)63-100 99.4

(2.8)88-100 5.9** .179 SLI = ADHD+LI <

TDIrregular correct 49.5

(19.7)0-75 42.9

(28.4)0-100 83.9

(23.3)25-100 15.9*** .370 SLI = ADHD+LI <

TD                   

* p < .05, ** p <.01, *** p <.001

Combined clinical and community samples (n = 57, 7- 9-years): Redmond, Ash, & Hogan (under review)

Page 53: Markers, models, and measurement error:

   SLI

(n =19)

 ADHD+LI(n =19)

 TD

(n =19)

 F

(2,54)

 Partial η2

 Contrasts

M (SD)

Range M (SD)

Range M (SD)

Range      

                   1.Nonword Rep. 79.1

(9.2)54.2-90 81.1

(8.6)66-97.9 89.6

(6.7)69.8-97.9 8.71** .244 SLI = ADHD+LI <

TD2. Sentence Recall

11.7(6.9)

0-26 14.7(7.3)

1-27 24.4(4.1)

15-31 21.3*** .441 SLI = ADHD+LI < TD

3. TEGI                  3rd person present 84.9

(24.1)0-100 91.0

(16.1)33-100 99.4

(2.5)89-100 3.6* .117 SLI = ADHD+LI <

TDRegular past 77.4

(29.7)0-100 84.63

(16.8)40-100 97.0

(4.7)90-100 4.7* .147 SLI = ADHD+LI <

TDIrregular finite 79.4

(27.4)0-100 89.53

(14.5)63-100 99.4

(2.8)88-100 5.9** .179 SLI = ADHD+LI <

TDIrregular correct 49.5

(19.7)0-75 42.9

(28.4)0-100 83.9

(23.3)25-100 15.9*** .370 SLI = ADHD+LI <

TD                   

* p < .05, ** p <.01, *** p <.001

Combined clinical and community samples (n = 57, 7- 9-years): Redmond, Ash, & Hogan (under review)

Page 54: Markers, models, and measurement error:

Diagnostic ConversionsNonword Repetition

• SLI: z score = -1.567; standard score = 76.5• ADHD+LI: z score = -1.27; standard score = 80.95

Sentence Recall • SLI: z score = -3.10; standard score = 53.5 • ADHD+LI: z score = -2.37; standard score = 64.45

TEGI Screening (-3s, -ed, ptirr) • SLI: z score = -8.9 ; standard score = < 0.1 • ADHD+LI: z score = -5.37 ; standard score = 19.45

Page 55: Markers, models, and measurement error:
Page 56: Markers, models, and measurement error:
Page 57: Markers, models, and measurement error:
Page 58: Markers, models, and measurement error:

  1. 2. 3. 4. 5. 6. 7.1.DSM-ADHD -- .225 .322* .314† .124 .225 .1242.Nonword Rep.   -- .408* .545*** .532** .487** .427**3. Sentence Recall     -- .569** .433** .507** .388*4. 3rd person pres.       -- .700*** .743*** .536**5. Regular Past         -- .852*** .494**6. Irregular finite           -- .523**7. Irregular correct             -- N = 38 (SLI and ADHD+LI combined) † p = .055* p < .05, ** p <.01, *** p <.001

Zero order Pearson product correlations among CBCL DSM-ADHD scale and language measures Redmond, Ash, & Hogan (under review)

Page 59: Markers, models, and measurement error:

  1. 2. 3. 4. 5. 6. 7.1.DSM-ADHD -- .225 .322* .314† .124 .225 .1242.Nonword Rep.   -- .408* .545*** .532** .487** .427**3. Sentence Recall     -- .569** .433** .507** .388*4. 3rd person pres.       -- .700*** .743*** .536**5. Regular Past         -- .852*** .494**6. Irregular finite           -- .523**7. Irregular correct             -- N = 38 (SLI and ADHD+LI combined) † p = .055* p < .05, ** p <.01, *** p <.001

Zero order Pearson product correlations among CBCL DSM-ADHD scale and language measures Redmond, Ash, & Hogan (under review)

Page 60: Markers, models, and measurement error:

Summary: Clear Phenotypic Boundaries

• Differential Diagnosis: • Language: Presence/absence or severity of ADHD had little impact on clinical

markers of SLI. EF deficits have not been associated with LI symptoms.• Behavior: Adjusted parent rating scales can differentiate SLI from ADHD with high

levels of accuracy. Hyperactivity/impulsivity symptoms scales particularly effective. Teacher ratings biased against SLI.

• ADHD and LI are non-interactive disorders: However, ADHD status might represent a buffer against risk for poorer outcomes if it encourages earlier referral and/or more intensive intervention.

Page 61: Markers, models, and measurement error:

Sentence RecallTense Marking, Nonword Rep,Adjusted Parent Rating scales

Page 62: Markers, models, and measurement error:

OTHER CONSIDERATIONS

Page 63: Markers, models, and measurement error:

Theory Testing: ADHD as the preferred control group for SLI studies • Cardy, Tannock, Johnson, & Johnson (2011):

• Groups: SLI, ADHD (w/normal language), and TD

• Measures: Auditory Repetition test, Simple Reaction Time task, Visual Search task (“impaired temporal processing” and “generalized slow processing” accounts)

• Results: ADHD group was significantly slower than the SLI group and both clinical groups were less accurate than the TD controls

• Conclusion: Processing dysfunctions are not unique to SLI and can occur in the absence

of language impairment. SLI can occur in the absence of processing dysfunction.

Page 64: Markers, models, and measurement error:

Theory Testing, cont’d

• Additional dysfunctions implicated in ADHD: dichotic listening, central auditory processing, implicit learning, procedural memory, working memory, serial reaction time, fine and gross motor skills (Barnes, et al., 2010; Nigg, 2006). Sound familiar?

• Advantages of cross-clinical comparisons

• Only cross-etiology comparisons can directly test whether dysfunctions are unique to a particular clinical group and can evaluate causality (necessity and sufficiency). SLI vs. TD comparisons can’t.

• Clinical groups would be more similar across key variables: • Nonverbal IQ levels• Demographic profiles (e.g. mother’s education level)• Experiences/exposures: e.g. academic failure, stigmatization, peer rejection, clinical services• Motivations for research participation: crisis vs curiosity

Page 65: Markers, models, and measurement error:

Links With Other DomainsSLI-Peer Victimization-ADHD Pathway

• Early Peer Victimization Linked to Later ADHD (Holmberg & Hjern, 2008).• 1st grade bullying levels associated with 4th grade ADHD symptoms……• ….BUT 1st grade ADHD was not significantly associated with 4th grade bullying

levels.• For some children, “PTSD-type” mechanism establishing/aggravating ADHD or

ADHD phenocopy.

• SLI Linked to Peer Victimization• Children/adolescents with SLI at increased risk for peer victimization relative to

TD and ADHD comparisons (Knox & Conti-Ramsden, 2007; Redmond, 2011).• Levels of reported physical and verbal bullying linked to ADHD symptoms in SLI

group but not in ADHD group (Redmond, 2011).

Page 66: Markers, models, and measurement error:

Links With Other DomainsSLI-Peer Victimization-ADHD Pathway cont’d• SLI Linked to Other Forms of Victimization

• Women with a history of SLI at increased risk for sexual assault relative to controls: 45.5% vs. 16.3%; OR = 4.08 (no differences between men w/w-out LI) (Brownlie et al., 2007).

• Epidemiological study combining school-based disability criteria from school database with social services records found that children with “speech-language impairments” had relative to non-disabled peers (Sullivan & Knutson, 2000): • 5 times the risk for neglect and physical abuse• 3 times the risk for sexual abuse • Almost 7 times the risk for emotional maltreatment• Relative risks higher than those associated with LD, MR, HI, VI, or autism designations

• Maltreatment linked to deficits in children’s emotional understanding and theory of mind, even when accounting for general language abilities (e.g. Cicchetti et al., 2003; Pears & Fisher, 2005).

Page 67: Markers, models, and measurement error:

Links With Other DomainsSLI-ADHD-RD Pathways

• Possible links between LI, ADHD, and RD

• ADHD symptoms might represent moderators of the LI-RD link, such that reading difficulties emerge in the ADHD+LI sub-group because behavioral difficulties compromise joint reading and other foundational experiences (e.g. McGinty & Justice, 2009).

• Reading difficulties might represent a mediator for the LI-ADHD link, such that ADHD and other externalizing behavior problems are secondary consequence of reading/academic failure (e.g. Tomblin, Zhang, Buckwalter & Catts, 2000).

Page 68: Markers, models, and measurement error:

NON-LI CASES (n =76): “Coalition Model for Decoding Skills”

Page 69: Markers, models, and measurement error:

LI CASES (n =46): “Language Model for Decoding Skills”

Page 70: Markers, models, and measurement error:

LI CASES: “Nonword Repetition Model for Decoding Skills”

Page 71: Markers, models, and measurement error:

• Non-invariant models: relations among these domains were not the same for cases of LI and non-LI

• Moderator/mediator models reported by other investigators were tested but not supported (McGinty & Justice, 2009; Tomblin, Zhang, Buckwalter & Catts, 2000)

• Adding nonverbal IQ, working memory (verbal, spatial), sentence recall, TEGI, or mother’s education level didn’t improve any of the models

Page 72: Markers, models, and measurement error:

Because of his learning disability, with the reading, the language has always been the backburner, you know what I mean? They figure well, if he would learn to read or if we could help him learn to read or learn to help with this and this and this, then the language thing would probably go away to a point. So, it seems like it was never that huge to anyone else but us.

….They're always like it might be his hearing, and we're like it's been checked a hundred times.

Parent of a 9-year old participant with SLI

CONCLUDING THOUGHTS

Page 73: Markers, models, and measurement error:

Implications for Clinical Practice, cont’d• Addressing unmet language needs of students with ADHD+LI

• One reoccurring observation in the literature over the past two decades has been the high rates of unidentified LIs in study samples of ADHD (cf. Cohen et al., 1998; Walsh et al., 2014).

• Possible responses: • “… conduct language assessments on all children with ADHD…” (Westby & Watson,

2010, p, 545)

• “… so, you’re suggesting that I need to double my caseload?” (anonymous SLC SLP)

• Timler (2013) demonstrated feasibility of using CCC-2 as a screening instrument for identifying co-occurring LI in students with ADHD

Page 74: Markers, models, and measurement error:

Implications for Clinical Practice

• Addressing the unmet language needs of students with SLI

• The costs of continued “diagnostic agnosticism”• Engage in differential diagnosis. Promote use of SLI term in diagnostic reports,

inter-professional communications, and in public discourse (Schuele & Hadley, 1999)

• The costs of continued reliance on “teacher as test”• Clinical markers are supported by the evidence, quick, free, and yet under-utilized• SLP selection of measures haven’t aligned well with their psychometric integrity

(Betz et al., 2013)

Page 75: Markers, models, and measurement error:

• Diagnostic agnosticism + teacher as test = disparities in service provision• “…boys were more likely to have received intervention even with the

same diagnosis” [OR: 1.8] (Zhang & Tomblin, 2000 p. 352; see also Jones et al., 2014)

• Consider peer victimization as a potential contributing factor to socioemotional behavioral/pragmatic symptoms• Screen our caseloads for bullying risk. Children who are being victimized

must be provided with protection and support and their bullies identified and dealt with

Page 76: Markers, models, and measurement error:

Implications for Research • Research

• Focus our inquiries on expanding our inventories of clinical markers capable of differential diagnosis across the lifespan

• Use clinical markers as entry criteria in the next rounds of epidemiological/longitudinal studies

• Establish regional variation associated with prevalence and diagnostic rates of SLI and ADHD+LI comorbidity

• Curb our enthusiasm for information processing models of SLI until they’ve been tested against ADHD

• Genetics/Neuroimaging? (Mueller, 2012).

Page 77: Markers, models, and measurement error:

Thank you for your attention

[email protected]

Page 78: Markers, models, and measurement error:

References American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders-5th Edition (DSM-5).

Washington, DC, American Psychiatric Association, 2013.American Speech-Language-Hearing Association. (2008). 2008 Schools Survey report: Caseload characteristics.

Rockville, MD: Author.Ash, A.C., & Redmond, S.M. (2014). An exploratory analysis of children’s social (pragmatic) symptoms. Poster

Presentation, Symposium for Research in Child Language Disorders, Madison: WI. Barnes, K.A., Howard, J.B., Howard, D., Kenealy, C.V., Vaidya, C.J. (2010). Two forms of implicit learning in childhood

ADHD. Developmental Neuropsychology, 35 (5), 494-505.Barkley. R.A. (2006). Attention-deficit hyperactivity disorder: A handbook for diagnosis and treatment. 3rd edition. New

York, NY: Guilford Press. Beitchman, J., Hood, J., Inglis, A. (1990). Psychiatric risk in children with speech and language disorders. Journal of

Abnormal Child Psychology, 18(3), 283-296.Benasich, A., Curtiss, S., & Tallal, P. (1993). Language, learning, and behavioral disturbance in childhood: A

longitudinal perspective. Journal of the American Academy of Child and Adolescent Psychiatry, 32, 585-594.Betz, S.K., Eickhoff, J.R., & Sullivan, S.F. (2013). Factors influencing the selection of standardized tests for the diagnosis

of specific language impairment. Language, Speech, and Hearing Services in Schools, 44, 133-146.Biederman, J., Keenan, K., & Faraone, S.V. (1990). Parent-based diagnosis of attention-deficit/hyperactivity disorder

predicts a diagnosis based on teacher reports. Journal of the American Academy of Child and Adolescent Psychiatry, 29, 698-701.

Bishop, D.V.M. (2006). Children’s Communication Checklist-2 (United States Edition). San Antonio, TX: Harcourt Assessment, Inc.

Bishop, D.V.M. (2010). Which neurodevelopmental disorders get researched and why? PLoS ONE, 5 (11), 1-9. Bishop, D. V.M. & Baird, G. (2001). Parent and teacher report of pragmatic aspects of communication: Use of the

Children’s Communication Checklist in a clinical setting. Developmental Medicine & Child Neurology, 43, 809-819.Bishop, D.V.M., McDonald, D., Bird, S., & Haiyou-Thomas, M.E. (2009). Children who read words accurately despite

language impairment: Who are they and how do the do it? Child Development, 80, 593-605. Brock, S.E., Jimerson, S.R., & Hansen, R.L. (2009). Identifying, Assessing, and Treating ADHD at School. New York, NY:

Springer.

Page 79: Markers, models, and measurement error:

Brownlie, E.B., Jabbar, A., Beitchman, J., Vida, R., & Atkinson, L. (2007). Language impairments and sexual assault of girls and women: Findings from a community sample. Journal of Abnormal Child Psychology, 35, 618-626.

Bruce, B., Thernlund, G., & Nettelbladt, U. (2006). ADHD and language impairment: A study of the parent questionnaire FTF (Five to Fifteen). European Child and Adolescent Psychiatry, 15, 52–60.

Camarata, S.M., Hughes, C.A., & Ruhl, K.L. (1988). Mild/moderate behaviorally disordered students: A population at risk for language disorders. Language, Speech, and Hearing Services in Schools, 19, 191-200.

Cardy, J.E.O., Tannock, R., Johnson, A., & Johnson, C.J. (2010). The contributions of processing impiarments to SLI: Insights from attention-deficit/hyperactivity disorder. Journal of Communication Disorders, 43, 77-91.

Catts, H.W., Adlof, S.M., Hogan, T.P., & Ellis-Weismer, S. (2005). Dyslexia and specific language impairment: Same or different developmental disorder? Journal of Speech, Language, and Hearing Research, 48, 1378-1396.

Centers for Disease Control and Prevention (March, 2013). 2011-2012 National Survey of Children’s Health. Available from URL: http://www.cdc.gov/nchs/slaitis/nschs.htm

Charach, A., Chen, S., Hogg-Johnson, S., & Schachar, R. (2009). Using the Conners’ Teacher Rating Scale-Revised in school children referred for assessment. The Canadian Journal of Psychiatry, 54, 232-241.

Cohen, N., Barwick, M., Horodezky, M., Vallance, D., & Im, N. (1998). Language, achievement, and cognitive processing of psychiatrically disturbed children with previously unidentified and unsuspected language impairments. Journal of Child Psychology and Psychiatry, 39(6), 865–877.

Cohen, N., Vallance, D., Barwick, M., Im, N., Menna, R., Horodezky, N., & Isaacson, L. (2000). The interface between ADHD and language impairment: An examination of language, achievement, and cognitive processing. Journal of Child Psychology and Psychiatry, 41(3), 353-362.

Conti-Ramsden, G., Botting, N., & Faragher, B. (2001). Psycholinguistic markers for specific language (SLI). Journal of Child Psychology and Psychiatry, 42, 741-748.

Dollaghan, C., & Campbell, T. (1998). Nonword repetition and child language impairment. Journal of Speech, Language, and Hearing Research, 41, 1136-1146.

Dupuy, T.R., & Greenberg. L.M. (1993). Test of Variables of Attention Manual. Minneapolic, MN: Lawrence M. Greenberg.Elbro, C., Dalby, M., & Maarjberg, S. (2011). Language-learning impairment: A 30-year follow-up of language-impaired

children with and without psychiatric, neurological and cognitive difficulties. International Journal of Language and Communication Diosrders, 46, 437-448.

Fey, M.E., Cats, H.W., Proctor-Williams, K., Tomblin, J.B., & Zhang, X. (2004). Oral and written story compositions skills of children with language impairment. Journal of Speech, Language, and Hearing Research, 47, 1301-1381.

Fine, J. (2006). Language in Psychiatry: A Handbook of Clinical Practice. London, UK: Equinox.

Page 80: Markers, models, and measurement error:

Finneran, D.A., Francis, A.L., & Leonard, L.B. (2009). Sustained attention in children with specific language impairment (SLI). Journal of Speech, Language, and Hearing Research, 52, 915-929.

Garcia-Real, T., Diaz-Roman, T.M., Garcia-Martinez, V., & Vierio-Iglesias, P. (2013). Clinical and acoustic vocal profile in children with attention deficit hyperactivity disorder. Journal of Voice, 27 (6), 11-18

Geurts, H., Verte, S., Oosterlaan, J., Roeyers, H., Hartman, C., Mulder, E., Sergeant, J. (2004). Can the Children’s Communication Checklist differentiate between children with autism, children with ADHD, and normal controls? Journal of Child Psychology and Psychiatry, 45, 1437–1453.

Geurts, H. & Embrechts, M. (2008). Language Profiles in ASD, SLI, and ADHD. Journal of Autism and Developmental Disorders, 38, 1931-1943.

Gillam, R. & Pearson, N. (2004). Test of Narrative Language (TNL). Austin, TX: PRO-ED.Gillam, R. B., Montgomery, J. W., Gillam, S. L. (2009). Attention and memory in child language disorders. In R. G. Schwartz (Ed.), Handbook

of child language disorders (pp. 201-215). New York: Psychology Press.Gualtieri, C.T., Koriath, U., Van Bourgondien, M.E., & Saleeby, N. (1983). Language disorders in children referred for psychiatric services.

Journal of the American Academy of Child Psychiatry, 22, 165-171. Hamdan, A., Deeb, R., Sibai, A., Rifai, H., Fayyad, J. (2009). Vocal characteristics in children with attention deficit hyperactivity disorder.

Journal of Voice, 23 (2), 190-194. Hedenius, M., Persson, J., Tremblay, A., Adi-Japha, E., Veríssimo, J., Dye, C., Alm, P., Jennische, M., Tomblin, J. B., Ullman, M.T. (2011).

Grammar predicts procedural learning and consolidation deficits in children with specific language impairment. Research in Developmental Disabilities, 32(6), 2362-2375.

Helland, W., Biringer, E., Helland, T., & Heimann, M. (2012). Exploring language profiles for children with ADHD and children with Asperger Syndrome. Journal of Attention Disorders, 16, 34-43.

Helland, W. & Heimann, M. (2007). Assessment of pragmatic language impairment in children referred to psychiatric services: A pilot study of the Children’s Communication Checklist in a Norwegian sample. Logopedics Phoniatrics Vocology, 32, 23-30.

Henry, L.A., Messer, D., & Nash, G. (2012). Executive functioning in children with specific language impairment. Journal of Child Psychology and Psychiatry, 53 (1), 37-45.

Im-bolter, N., Cohen, N., & Farnia, F. (2013). I thought we were good: Social cognition, figurative language, and psychopathology. Journal of Child Psychology and Psychiatry, doi:10.1111/jcpp.12067.

Jones, L.I., Vahratian, A., Hoffman, H., Li, C., & Rice, M.L. (2014). Voice, speech, and language disorders among children aged 3-17 years: Who are the children not receiving intervention services? City MatCH Leadership & MCH Epidemiology Conference. Phoenix, AZ Sept 17-19. 2014

Johnson, C., Beitchman, J. H., Escobar, M., Atkinson, L., Wilson, B., Brownlie, E. B., Douglas, L., Taback, N., Lam, I., & Wang, M. (1999). Fourteen-year follow-up of children with and without speech/language impairments: Speech/language stability and outcomes. Journal of Speech, Language, and Hearing Research, 42, 744–760.

Page 81: Markers, models, and measurement error:

Ketelaars, M., Cuperus, J., Jansonius, K., & Verhoeven, L. (2010). Pragmatic language impairment and associated behavioural problems. International Journal of Language and Communication Disorders, 45, 204-214.

Knox, E., & Conti-Ramsden, G. (2007). Bullying in young people with a history of specific language impairment. Educational and Clinical Psychology, 24, 130-141.

Law, J., Rush, R., Schoon, I., Parsons, S. (2009). Modeling developmental language difficulties from school entry into adulthood: Literacy, mental health, and employment outcomes. Journal of Speech, Language, and Hearing Research, 52, 1401-1416.

Lahey, B.B., Pelham, W.E., Loney, J., Lee, S.S., Willcutt, E. (2005). Instability of the DSM-IV subtypes of ADHD from preschool through elementary school. Arch Gen Psychiatry 62, 896-902.

Leonard, M. Milich, R. & Lorch, P. (2011). The role of pragmatic language use in mediating the relation between hyperactivity and inattention and social skills problems. Journal of Speech, Language, and Hearing Research, 54, 567-579. DOI: 10.1044/1092-4388(2010/10-0058)

Lindsay, G., & Dockrell, J.E. (2008). Outcomes for young people with a history of specific language impairment at 16-17 years: A more positive picture? In V. Joffe, M., Cruice, & S. Chiat (Eds.), Language disorder in children and adults: New issues in research and practice (pp. 138-159).

Lindsay, G., Dockrell, J., Strand, S., (2007). Longitudinal patterns of behaviour problems in children with specific speech and language difficulties: Child and contextual factors. British Journal of Educational Psychology, 77(4), 811-828.

Love, A.J., & Thompson, M.G.G. (1988). Language disorders and attention disorders in young children referred for psychiatric services: Analysis of prevalence and a conceptual synthesis. American Journal of Orthopsychiatry, 58, 52-64.

Luo, F., & Timler, G. (2008). Narrative organization skills in children with attention deficit hyperactivity disorder and language impairment: Application of the causal network model. Clinical Linguistics and Phonetics, 22, 25–46.

Merwood, A., Grevan, C.U., Price, T.S., Rijsdijk, F., Kuntsi, J., McLoughlin, G., Larsson, H., & Asherson, P.J. (2013). Different heritabilities but shared etiological influences for parent, teacher, and self-ratings of ADHD symptoms: An adolescent twin study. Psycohlogical Medicine, 43, 1973-1984.

Page 82: Markers, models, and measurement error:

Milberger, S., Biederman, J., Faraone, S.V., Muprhy, J., & Tsuang, M.T. (1995). Attention-deficit/hyperactivity disorder nad comorbid disorders: Issues of overlapping symptoms. American Journal of Psychiatry, 12, 1793-1799.

Milch-Reich, S., Campbell, S., Pelham, W., Connelly, L., & Geva, D. (1999). Developmental and individual differences in children's on-line representations of dynamic social events. Child Development, 70(2), 413-431.

McGinty, A.S., Justice, L.M. (2009). Predictors of print knowledge in children with SLI: Experiential and developmental factors. Journal of Speech, Language, and Hearing Research, 52, 81-97.

Mueller, K.L. (2012). Causation, correlation, or confound? What the comorbidity of language impairment and ADHd can tell us about the etiology of these disorders. Doctoral Dissertation, University of Iowa.

Naglieri, J.A. (2003). Naglieri Nonverbal Ability Test-Individual Administration Manual. San Antonio, TX: Psychological Corporation. Nippold, M.A., Mansfield, T.C., Billow, J.L., & Tomblin, J.B. (2008). Expository discourse in adolescents with language impairments: Examining

syntactic development. American Journal of Speech-Language Pathology, 17, 356-366. Nigg, J.T., Willcutt, E.G., Doyle, A.E., Sonuga-Barke, E. (2005). Causal heterogeneity in attention-deficit/hyperactivity disorder: Do we need

neuropsychologically impaired subtypes?Biological Psychiatry, 57, 1224-1230. Norbury, C. (2013). Practitioner review: Social (pragmatic) communication disorder conceptualization, evidence and clinical implications.

Journal of Child Psychology and Psychiatry, doi:10.1111/jcpp.12154. Parigger, E. (2012). Language and executive functioning in children with ADHD. University of Amsterdam Press. Pearce, W.M., James, D.G.H., & McCormack, P.F. (2010). A comparison of oral narratives in children with specific language impairment and

non-specific language impairment. Clinical Linguistics and Phonetics, 24, 622-645. Redmond, S.M. (2002). The use of rating scales with children who have language impairments: A tutorial. American Journal of Speech

Language Pathology, 11, 124-138.Redmond, S.M. (2004). Conversational profiles of children with ADHD, SLI and typical development. Clinical Linguistics and Phonetics, 18,

107-125.Redmond, S.M., (2005). Differentiating SLI from ADHD using children’s sentence recall and production of past tense morphology. Clinical

Linguistics & Phonetics, 19, 109-127.Redmond, S.M. (2011). Peer victimization among students with specific language impairment, attention-deficit/hyperactivity disorder, and

typical development. Language, Speech, and Hearing Services in Schools, 42, 520535. Redmond, S.M., & Ash, A.C. (2014). A cross-etiology comparison of the socioemotional behavioral profiles associated with attention-

deficit/hyperactivity disorder and specific language impairment. Clinical Linguistics and Phonetics, 28 (5), 346-365. Redmond, S.M., Ash, A.C., & Hogan, T.P. (under review). Consequences of co-occurring attention-deficit/hyperactivity disorder on children’s

language impairments. Redmond, S. M. & Rice, M.L. (2002). Stability of behavioral ratings of children with specific language impairment. Journal of Speech,

Language, and Hearing Research, 45, 190-201. Redmond, S.M., Thompson, H.L., & Goldstein, S. (2011). Psycholinguistic profiling differentiates specific language impairment from typical

development and from attention deficit/hyperactivity disorder. Journal of Speech, Language, and Hearing Research, 41, 688-700.

Page 83: Markers, models, and measurement error:

Rescorla, L., Ross, G.S., & McClure, S. (2007). Language delay and behavioral/emotional problems in toddlers: Findings from two developmental clinics. Journal of Speech, Language, and Hearing Research, 50, 1063-1078.

Riccio, C.A., Reynolds, C.R., & Lowe, P.A. (2001). Clinical Applications of Continuous Performance Tests: Measruning Attention and Impulsive Responding in Children and Adults. New York, NY: John Wiley and Sons.

Rice, M.L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychological Corporation.

Rice, M.L., Tomblin, J.B., Hoffman, L., Richman, W.A., & Marquis, J. (2004). Grammatical tense deficits in children with SLI and nonspecific language impairment: Relationships with nonverbal IQ over time. Journal of Speech, Language, Hearing Research, 47, 816-834.

Rielly, N.E., Cunningham, C.E., Rcihards, J.E., Eldbard, H.J., & Mahoney, W.J. (1999). Detecting attention deficit hyperactivity disorder in a communications clinic: Diangostic utility of Gordon Diagnostic System. Journal of Clinical and experimental Neuropsychology, 21, 685-700.

Schachar, R., Sandberg, S., & Rutter, M. (1986). Agreement between teacher’s ratings and observations of hyperactivity, inattentiveness, and defiance. Journal of Abnormal Child Psychology, 14 (2), 331-345.

Sharp. S. Arora, T., Smith, P.K., & Whitney, I. (1994). How to measure bullying in your school. In S. Sharp & P.K. Smith (Eds.), Tackling bullying in your school: A practical handbook for teachers. (pp. 7-21). New York, NY: Routledge.

Snowling, M.J., Bishop, D.V.M., Sothard, S.E., Chipchase, B., & Caplan, C. (2006). Psychosocial outcomes at 15 years of children with a preschool history of speech-language impairment. Journal of Child Psychology and Psychiatry, 47, 759-765.

Spaulding, T.J., Plante, E., & Farienlla, K.A. (2006). Eligibility criteria for language impairment: Is the low end of normal laways appropriate? Language, Speech, and Hearing Services, 37, 61-72.

 St Clair, C. Pickles, A., Durkin, K., Conti-Ramsden, G. (2011). A longitudinal study of behavioral, emotional and social difficulties in individuals with a history of specific language impairment (SLI), Journal of Communication Disorders, 44(2), 186-199.

Stanton-Chapman, T.L., Justice, L.M., Skibbe, L.E., & Grant, S.L. (2007). Social and behavioral characteristics of preschoolers with specific language impairment. Topics in Early Childhood Special Education, 27, (2), 98-109.

Page 84: Markers, models, and measurement error:

Sullivan, P.M., & Knutson, J.F. (2000). Maltreatment and disabilities: A population based epidemiological study. Child Abuse and Neglect, 24 (10), 1257-1273.

Tannock, R., Purvis, K., & Schachar, R. (1993). Narrative abilities in children with attention deficit hyperactivity disorder and normal peers. Journal of Abnormal Child Psychology, 21(1), 103-117.

Tannock, R., & Schachar, R. (1996). Executive dysfunction as an underlying mechanism of behaviour and language problems in attention deficit hyperactivity disorder. In J. H. Beitchman, N. J. Cohen, M. M. Konstantareas, & R. Tannock (Eds.), Language, Learning, and Behaviour Disorders: Developmental, Biological, and Clinical Perspectives (pp. 128–155). Cambridge: Cambridge University Press.

Timler, G. (2014). Use of the Children’s Communication Checklist-2 for Classification of Language Impairment Risk in Young School-Age Children with Attention-Deficit/Hyperactivity Disorder. American Journal of Speech-Language Pathology, 23, 73-83. .

Tirosh, E., & Cohen, A. (1998). Language deficit with attention-deficit disorder: A prevalent comorbidity. Journal of Child Neurology, 13, 493-497.

Tomblin, J. B., Records, N., Buckwalter, P., Zhang, X., Smith, E., & O’Brien, M. (1997). Prevalence of Specific Language Impairment in Kindergarten Children. Journal of Speech, Language, and Hearing Research, 40, 1245-1260.

Tomblin, J.B., Zhang, X., Buckwalter, P., & O’Brien, M. (2003). The stability of primary language disorder: Four years after kindergarten diagnosis. Journal of Speech, Language, and Hearing Research, 46, 1283-1296.

Tomblin, J.B., Zhang, X., Buckwalter, P., & Catts, H. (2000). The association of reading disability, behavioral disorders, and language impairment among second-grade children. Journal of Child Psychology and Psychiatry, 41, 473-482.

Trautman, R. C., Giddan, J. J., & Jurs, S. G. (1990). Language risk factor in emotionally disturbed children within a school and day treatment program. Journal of Childhood Communication Disorders, 13, 123–133.

Valieski, T.N., & Stipek, D.J. (2001). Young children’s feelings about school. Child Development, 72, 1198-1213. Wachs, T.D. (2000). Necessary but not sufficient: The respective roles of single and multiple influences on individual

development. Washington, DC: American Psychological Association. Walsh, I.P., Scullion, M., Burns, S., MacEvilly, D., & Brosnan, G. (2013). Identifying demographic and language profiles of

children with a primary diagnosis of attention deficit hyperactivity disorder. Emotional and Behavioral Difficulties, 19 (1), 59-70.

Wetherell, D., Botting, N., & conti-Ramsden, G. (2007). Narrative skills in adolescents with a history of SLI in relation to non-verbal IQ scores. Child Language Teaching and Therapy, 23, 95-113.

Page 85: Markers, models, and measurement error:

Warr-Leeper, G., Wright, N., Mack, A. (1994). Language disabilities of antisocial boys in residential treatment. Behavioral Disorders, 19(3), 159-169.

Westby, C., & Watson, S. (2010). ADHD and communication disorders. In J.S. Damico, N. Mueller, and M.J. Ball (Eds) The Handbook of Language and Speech Disorders. (pp. 528-555). West Sussex, UK: Wiley.

Whitehouse, A.J.O., Robinson, M., & Zubrick, S.R. (2011). Late talking and the risk for psychosocial problems during childhood and adolescence. Pediatrics, 128 (2), 324-332.

Willcutt, E. G. (2012). The prevalence of DSM-IV attention-deficit/hyperactivity disorder: A meta-analytic review. Neurotherapeutics, 9, 490-499.

Willcutt, E.G., Doyle, A.E., Nigg, J.T., Faraone, S.V., & Pennington, B.F. (2005). Validity of the executive function theory of attention-deficit/hyperactivity disorders: A meta-analytic review. Biological Psychiatry, 57, 1336-1346.

Willinger, U., Brunner, E., Diendorfer-Radner, G., Mag, J.S., Sirsch, U., & Eisenwort, B. (2003). Behavior in children with language development disorders. Canadian Journal of Psychiatry, 48, 607-614.

Windsor, J. & Kohnert, K. (2009). Processing speed, attention, and perception in child language disorders. In R. Schwartz (Ed.,), Handbook of child language disorders (pp. 445-461). New York: Psychology Press.

Zhang, X. and Tomblin, J.B., ( 2000). The Association of intervention receipt with speech-language profiles and social demographic variables. American Journal of Speech-Language Pathology, 9, 345-357.