Utility of a CPT in Diagnosing ADHD among a Representative Sample of High-Risk Children: A Cautionary Study

Abstract

Continuous performance tests (CPTs) are widely used in the assessment and study of attention deficit hyperactivity disorder (ADHD). Although CPTs have reliably found differences between children with ADHD and normal controls, discriminating between children with ADHD and children with subclinical levels of behavioral or cognitive problems is a more clinically relevant and difficult endeavor. Additionally, most studies use convenience samples from clinical care settings that may not represent the ADHD population as a whole. The current study assessed the utility of a clinically used CPT, the Test of Variables of Attention (TOVA), in distinguishing between children with ADHD and children with subclinical levels of attention/behavior problems. Participants constituted a representative sample of elementary school students at high risk for ADHD, including 116 children with ADHD and 51 subclinical controls. Results found no significant differences between the ADHD and subclinical group on CPT variables, and CPT performance did not reliably predict group membership. Implications of the findings are discussed.

The Test of Variables of Attention (TOVA): Internal Consistency (Q1vs. Q2and Q3vs. Q4) in Children with Attention Deficit/Hyperactivity Disorder (ADHD)

“…Kamphaus & Frick, 1996;Preston et al, 2005;Riccio et al, 2001), particularly when used to differentiate ADHD from other disorders (Barkley, 1998), or different ADHD subtypes, CPTs may not be the cause of the problem. Rather, the disorders and the amount of variance they share or their encroachment on attentional mechanisms as measured by reaction time tests, procedures with high sensitivity, may be responsible for the psychometric problem.…”

“…Despite the fact that CPTs have the potential to enhance the multimethod assessment of ADHD symptomatology and its diagnosis (Corkum & Siegel, 1993;Gordon, 1993;Perugini et al, 2000;Wada, Yamashita, Matsuishi, Ohtani, & Kato, 2000), their clinical utility, ecological validity, reliability, and discriminant validity (Barkley, 1991;Kamphaus & Frick, 1996;Leark, Wallace, & Fitzgerald, 2004;Preston, Fennell, & Bussing, 2005;Riccio et al, 2001) remain poorly understood. Notwithstanding recent research attempts to address specific properties of select CPTs (Boivin et al, 1996;Forbes, 1998;Llorente et al, 2001;and Losier, McGrath, & Klein, 1996), limited information is available in the literature, particularly for clinical groups with neuropsychological deficits including ADHD, related to the internal properties of these procedures.…”

Clinical and neuropsychological profile in a sample of children with attention deficit hyperactivity disorders

“…Children with ADHD presented a slower reaction time, more omission and commission errors when compared to children without ADHD, similarly to the findings in literature 22,23 . The specificity of the existing variables in the CPT is quite contradictory and sometimes inconsistent, especially when differentiating the ADHD subtypes 24,25 . we also must consider that small differences found in the correlations between the ADHD subtypes may have been influenced by the relatively small number cases in the hyperactive/impulsive subtype sample, but such finding is in line with those of other authors 5,26 , who report that although the CPT has high sensitivity (about 88% when detecting ADHD), it has low specificity (from 20 to 37%) when identifying the different subtypes.…”

Sources of Bias in Teacher Ratings of Adolescents with ADHD

“…Psychological tests also appear insufficient to diagnose ADHD because outcomes for individuals with and without the disorder largely overlap (i.e., poor instrument sensitivity and specificity), even though significant group differences are apparent between large samples (Frazier, Demaree, & Youngstrom, 2004). Similarly, group differences between ADHD and undiagnosed groups have been found on some neuropsychological measures, but these instruments are not sensitive or specific enough to diagnose individual cases (e.g., Homack & Riccio, 2004;Preston, Fennell, & Bussing, 2005). As a result, clinicians must rely primarily on behavioral observations-directly or indirectly-when assessing individual cases.…”