ARTICLES

Diagnostic Utility of Two Commonly Used ADHD Screening Measures Among Special Education Students

This chapter describes attention deficit hyperactivity disorder (ADHD) screening performance in preschool and school-age children and adolescents. Studies of large and community representative samples are emphasized, and the focus is on screening performance metrics that are comparable across studies (e.g., area under the receiver operating characteristic curve, likelihood ratio positive and negative, and positive and negative predictive values). Multiple assessment instruments can identify children and adolescents who probably have ADHD and those who probably do not with moderate-to-high sensitivity and moderate specificity in community samples. Specificity (the capacity to rule out the disorder) tends to be moderate because ADHD symptoms are common in children who meet diagnostic criteria for other neurodevelopmental and behavioral disorders. Variation in screening performance across studies appears to be attributed to differences in ADHD diagnostic methods (e.g., clinical examination vs. parent report), sample characteristics (e.g., age, sex, and comorbidities), and/or respondent type (e.g., parent vs. teacher).

The aim was to compare parent-reported symptoms of attention-deficit/hyperactivity disorder (ADHD) before (baseline) and two years after pediatric epilepsy surgery (follow-up). The parents of 107 children who underwent epilepsy surgery completed surveys including the Conners 10-item scale at baseline and follow-up. Changes in scores between baseline and follow-up were compared using paired sample t-test. Factors associated with changes in scores were analyzed using linear regression. Features of ADHD were significantly reduced at follow-up (p < 0.001). Items with the greatest reduction were items focusing on core aspects of the diagnostic criteria for ADHD. Fewer children were in the at-risk range for ADHD on the Conners 10-item scale at follow-up but this did not reach statistical significance (49% vs. 43%; p = 0.481). Factors independently significantly associated with improvement in ADHD symptoms on multivariable analysis were higher baseline scores (p < 0.001), seizure-free status (p = 0.029), and right-sided surgery (p = 0.031). Children who undergo epilepsy surgery have a high rate of ADHD symptoms. Parent-rated symptoms of ADHD improved at 2-year follow-up after epilepsy surgery. All children undergoing epilepsy surgery should undergo assessment for ADHD at baseline and follow-up.

The high prevalence and impact of neurodevelopmental comorbidities in childhood epilepsy are now well known, as are the increased risks and familial aggregation of reading disability (RD) and speech sound disorder (SSD) in rolandic epilepsy (RE). The risk factors for RD in the general population include male sex, SSD, and ADHD, but it is not known if these are the same in RE or whether there is a contributory role of seizure and treatment-related variables.

An observational study of 108 probands with RE (age range: 3.6–22 years) and their 159 siblings (age range: 1–29 years; 83 with EEG data) were singly ascertained in the US or UK through a proband affected by RE. We used a nested case–control design, multiple logistic regression, and generalized estimating equations to test the hypothesis of an association between RD and seizure variables or antiepileptic drug treatment in RE; we also assessed an association between EEG focal sharp waves and RD in siblings.

Reading disability was reported in 42% of probands and 22% of siblings. Among probands, RD was strongly associated with a history of SSD (OR: 9.64, 95% CI: 2.45–37.21), ADHD symptoms (OR: 10.31, 95% CI: 2.15–49.44), and male sex (OR: 3.62, 95% CI: 1.11–11.75) but not with seizure or treatment variables. Among siblings, RD was independently associated only with SSD (OR: 4.30, 95% CI: 1.42–13.0) and not with the presence of interictal EEG focal sharp waves.

The principal risk factors for RD in RE are SSD, ADHD, and male sex, the same risk factors as for RD without epilepsy. Seizure or treatment variables do not appear to be important risk factors for RD in probands with RE, and there was no evidence to support interictal EEG focal sharp waves as a risk factor for RD in siblings. Future studies should focus on the precise neuropsychological characterization of RD in families with RE and on the effectiveness of standard oral-language and reading interventions.

Our research on adverse effects of lead exposures on physical and neurobehavioral health of children aged 6–12 years in 4 villages, labeled as K, M, L, and X, in rural China, was reported in this article. Lead in blood (PbB), urine (PbU), hairs (PbH), and nails (PbN) were measured by graphite furnace atomic absorption spectrometry. Abbreviated Symptom Questionnaire of Conner's instruments and Revised Raven's Standard Progressive Matrices were applied to evaluate childhood attention deficit/hyperactivity disorders (ADHD) and intelligences. Geometric means (SD) of PbB, PbU, PbH and PbN concentrations were 71.2 μg/L (1.56), 11.7 μg/g (1.75), 12.5 μg/g (2.82), and 25.3 μg/g (2.79), respectively. 54 (17.0%) children had PbB levels of ≥ 100 μg/L. Boys, the 6–10 years old, and living in village K were 2.11, 2.48, and 9.16 times, respectively, more likely to be poisoned by lead than girls, aged 11–12 years, and residing in X. 18 (5.7%) and 37 (11.7%) subjects had ADHD and mental retardations, respectively. Inverse relationships between intelligences and natural log transformed PbU and PbH levels were observed with respective odds ratios (95%CI) of 1.79 (1.00–3.22) and 1.46 (1.06–2.03) or 1.28 (1.04–1.58) and 1.73 (1.18–2.52) by binary or ordinal logistic regression modeling. ADHD prevalence was different by gender and age of subjects. PbU, PbH, and PbN related to PbB positively with respective correlation coefficients of 0.530, 0.477, and 0.181. Receiver operating characteristic (ROC) curves of the three measurements reveled areas under curves (AUCs) being 0.829, 0.758, and 0.687, respectively. In conclusion, children had moderate levels of lead exposures in this rural area. Intelligence declines were associated with internal lead levels among children. ROC analysis suggests PbU an internal lead indicator close to PbB.

Previous validation studies of attention deficit/hyperactivity disorder (ADHD) assessment by rating scales or EEG have provided Class-IV evidence per standards of the American Academy of Neurology. To investigate clinical applications, we collected Class-I evidence, namely from a blinded, prospective, multi-center study of a representative clinical sample categorized with a clinical standard. Participating males (101) and females (58) aged 6 to 18 had presented to one of four psychiatric and pediatric clinics because of the suspected presence of attention and behavior problems. DSM-IV diagnosis was performed by clinicians assisted with a semi-structured clinical interview. EEG (theta/beta ratio) and ratings scales (Conners Rating Scales-Revised and ADHD Rating Scales-IV) were collected separately in a blinded protocol. ADHD prevalence in the clinical sample was 61%, whereas the remainder had other childhood/adolescent disorders or no diagnosis. Comorbidities were observed in 66% of ADHD patients and included mood, anxiety, disruptive, and learning disorders at rates similar to previous findings. EEG identified ADHD with 87% sensitivity and 94% specificity. Rating scales provided sensitivity of 38–79% and specificity of 13–61%. While parent or teacher identification of ADHD by rating scales was reduced in accuracy when applied to a diverse clinical sample, theta/beta ratio changes remained consistent with the clinician's ADHD diagnosis. Because theta/beta ratio changes do not identify comorbidities or alternative diagnoses, the results do not support the use of EEG as a stand-alone diagnostic and should be limited to the interpretation that EEG may complement a clinical evaluation for ADHD.

The objective was to investigate the effectiveness of rating scales and electroencephalography (EEG) in detecting the presence of attention-deficit/hyperactivity disorder (ADHD) within a diverse clinical sample. A standard psychiatric evaluation was used to assess 26 children/adolescents who presented to a clinic because a parent suspected the presence of ADHD. EEG data was collected in a blinded protocol, and rating scales were collected as well. Although all subjects had presented with ADHD-like symptoms, only 62% were diagnosed with ADHD, while the remaining 38% had other disorders or no diagnosis. Rating scales readily classified inattentive, impulsive, and/or hyperactive symptoms as being due to ADHD, regardless of the actual underlying disorder, leading to a sensitivity of 81% and a specificity of 22%. Previous studies have observed that there is an EEG marker that identifies ADHD vs. controls, and this marker was present in 15 out of 16 of the ADHD subjects (sensitivity = 94%) and in none of the subjects with ADHD-like symptoms due to other disorders (specificity = 100%). In the detection of ADHD in a diverse clinical sample, rating scales and EEG were both sensitive markers, whereas only EEG was specific. These results may have important implications to ADHD differential diagnosis.