Influence of relative age on diagnosis and treatment of attention-deficit/hyperactivity disorder in children

Teachers' perceptions of behavioral problems in Dutch primary education pupils: The role of relative age

A growing number of studies suggest that relatively young behavior of pupils gives them a much greater likelihood of being diagnosed with a disorder such as ADHD. This 'relative age effect' has also been demonstrated for special educational needs, learning difficulties, being bullied, and so on. The current study investigated the relationship between relative age of pupils in primary education and teachers' perception of their behavior. The study sample included 1973 pupils, aged between 6 and 12. Six linear mixed models were carried out with birth day in a year as predictor variable and 'total problem score', 'problems with hyperactivity', 'behavioral problems', 'emotional problems', 'problems with peers' and 'pro-social behavior' as dependent variables. Random intercepts were added for school and teacher level. Cluster-mean centering disaggregated between-school effects and within-school effects. We found no associations between relative age of pupils and teacher perceptions of their behavior. Several explanations are postulated to account for these findings which contradict prior studies on relative age effects.

Young age at school entry and attention-deficit hyperactivity disorder-related symptoms during primary school: results of a prospective cohort study conducted at German Rudolf Steiner Schools

OBJECTIVES

Young age at school entry (ASE) for students has been related to their impaired mental health in higher grades. To avoid the negative health consequences of young ASE, preschool examinations and individual school entry deferral for young children are routinely performed by some school authorities. We aimed to investigate whether ASE was associated with attention-deficit hyperactivity disorder (ADHD)-related symptoms in pupils attending schools using a selective school enrolment procedure.

DESIGN

Prospective open cohort study with baseline assessments at school entry and two follow-ups in the second and fourth grades.

SETTING

Up to 128 Rudolf Steiner Schools (Waldorf Schools) located within Germany.

PARTICIPANTS

Of the 3079 children from whom data were gathered in the second or fourth grade, 2671 children born between 1 July 2001 and 31 October 2002 (age at baseline: mean 6.7, min 5.91, max 7.24 years, 50% girls) were selected for analysis to avoid bias introduced by individuals at the edges of the ASE distribution.

MAIN OUTCOME MEASURES

ADHD-related symptoms were assessed at school entry and second and fourth grades by parent-reported and teacher-reported versions of the Strengths and Difficulties Questionnaire (Hyperactivity-Inattention Subscale).

RESULTS

The agreement between parent-reported and teacher-reported symptoms was poor (intra-class correlation: 0.41 and 0.44 in second and fourth grade assessments, respectively). Regarding teacher reports, ASE was negatively associated with ADHD-related symptoms in the second grade (regression coefficient β=-0.66 per year, P=0.0006) and fourth grade (β=-0.56, P=0.0014). Associations remained after adjusting for potential confounders and pre-existing symptoms at baseline. Regarding parent reports, associations were markedly weaker in both grades (second grade: β=-0.22, P=0.12; fourth grade: β=-0.09, P=0.48).

CONCLUSIONS

Using a prospective study design and comprehensive adjustment for confounding and baseline symptoms, we confirmed prior evidence of the association between young ASE and teacher-reported ADHD symptoms in primary school.

Influence of the relative age effect on children's scores obtained from the Canadian assessment of physical literacy

BACKGROUND

Age grouping by the imposition of a cut-off date, common in sports and education, promotes a relative age difference that is associated with developmental advantages for children who are born on the "early side" of the cut-off date and disadvantages to those born later in the same year, which is known as the relative age effect (RAE) bias. Acquiring an adequate level of physical literacy is important for children to remain active for life. The Canadian Assessment of Physical Literacy (CAPL) is an assessment protocol that encompasses measures in the domains of children's Daily Behaviours, Physical Competence, Motivation and Confidence, and Knowledge and Understanding. The purpose of this study was to ascertain whether the CAPL scores were susceptible to the RAE, which could affect our interpretation of the CAPL findings.

METHODS

This cross-sectional study examined if scores obtained in the CAPL (i.e., the four domains individually and the total CAPL score) were susceptible to the RAE in children aged 8 to 12 years and, if so, which physical competence assessments (movement skills, cardiorespiratory, strength, muscular endurance, flexibility, and body composition measurements) were more susceptible. Participants (n = 8233, 49.8% boys) from the Royal Bank of Canada-CAPL Learn to Play project from 11 sites in seven Canadian provinces were tested using the CAPL protocol.

RESULTS

Among boys and girls, the RAE was significantly associated with two and three of the four domain scores, respectively, after controlling for covariates. However, effect sizes were negligible for the comparisons between quarters of the year and physical literacy domains and overall scores. For the main effect of the relative age, boys and girls born in the first three months of the year were taller (F(3, 4074) = 57.0, p < 0.001, ƒ2 = 0.04 and F(3, 4107) = 58.4, p < 0.001, ƒ2 = 0.04, respectively) and demonstrated greater muscular strength (F(3, 4037) = 29.2, p < 0.001, ƒ2 = 0.02 and F(3, 4077) = 25.1, p < 0.001, ƒ2 = 0.02, respectively) compared with those born later in the same year.

CONCLUSIONS

Collectively, our results suggest that the RAE bias is mainly negligible with regard to the domain scores and overall CAPL scores in this large sample of children.

A Regional ADHD Center-Based Network Project for the Diagnosis and Treatment of Children and Adolescents With ADHD

OBJECTIVE

We aimed to define the sociodemographic, clinical, and prescription profiles of the participants enrolled in the Italian Lombardy ADHD Register.

METHOD

Data on patients evaluated by the 18 regional ADHD reference centers in the 2012 to 2013 period were analyzed.

RESULTS

Seven hundred fifty-three of 1,150 (65%) suspected patients received a diagnosis of ADHD. In 24% of cases, there was a family history of ADHD. Four hundred eighty-three (64%) patients had at least one psychopathological disorder, the more common of which were learning disorders (35%). Eighty-four percent of patients received a prescription for psychoeducational interventions, 2% received only pharmacological treatment, and 14% a combination of both. Compared with patients treated with psychoeducational intervention alone, patients with drug prescriptions more commonly presented values of Clinical Global Impressions - Severity scale (CGI-S) of 5 or higher ( p < .0001).

CONCLUSION

A continuous and systematic monitoring of patterns of care is essential in promoting significant improvements in clinical practice and ensuring an efficient and homogeneous quality of care.

Season of birth: A predictor of ADHD symptoms in early midlife

OBJECTIVE

In this longitudinal study, we applied linear regression analyses to examine season of birth as related to symptoms of attention deficit/hyperactivity disorder (ADHD) in early midlife.

METHOD

We gathered longitudinal data on a prospective cohort of community-dwelling men and women (N = 548) followed from adolescence to early midlife.

FINDINGS

The findings indicate that, as compared with participants who were born in the summer, those who were born in the spring (Beta = 0.34; t-statistic = 3.59; p < 0.001) had significantly more ADHD symptoms. In addition, exposure to maternal cigarette smoking in adolescence significantly intensified (p < 0.01) the association between season of birth and ADHD symptoms in early midlife.

CONCLUSION

These findings suggest that exposure to greater maternal maladaptive behaviors, such as cigarette smoking, may result in a greater vulnerability to other environmental risk factors, such as season of birth.

The gift of time? School starting age and mental health

Using linked Danish survey and register data, we estimate the causal effect of age at kindergarten entry on mental health. Danish children are supposed to enter kindergarten in the calendar year in which they turn 6 years. In a "fuzzy" regression-discontinuity design based on this rule and exact dates of birth, we find that a 1-year delay in kindergarten entry dramatically reduces inattention/hyperactivity at age 7 (effect size = -0.73), a measure of self-regulation with strong negative links to student achievement. The effect is primarily identified for girls but persists at age 11.

ADHD: a critical update for educational professionals

A medical approach towards behavioural problems could make professionals without a medical background, like teachers and other educational professionals feel inapt. In this article, we raise six scientifically grounded considerations regarding ADHD, currently the most prevalent childhood psychiatric diagnosis. These "need to knows" show just how misguided and potentially stigmatizing current conceptualizations of unruly behaviour have become. Some examples are given of how teachers are misinformed, and alternative ways of reporting about neuropsychological research are suggested. A reinvigorated conceptual understanding of ADHD could help educational institutions to avoid the expensive outsourcing of behavioural problems that could also-and justifiably better-be framed as part of education's primary mission of professionalized socialization.

Prevalence rates of youths diagnosed with and medicated for ADHD in a nationwide survey in Taiwan from 2000 to 2011

AIMS

Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan.

METHOD

Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year.

RESULTS

The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16).

CONCLUSIONS

The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40-50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.

Relative age within the school year and diagnosis of attention-deficit hyperactivity disorder: a nationwide population-based study

BACKGROUND

Findings are mixed on the relationship between attention-deficit hyperactivity disorder (ADHD) and younger relative age in the school year. We aimed to investigate whether relative age is associated with ADHD diagnosis in a country where prescribing rates are low and whether any such association has changed over time or relates to comorbid disorders (eg, conduct disorder [CD], oppositional defiant disorder [ODD], or learning disorder [LD]).

METHODS

We used nationwide population-based registers to identify all Finnish children born between Jan 1, 1991, and Dec 31, 2004, who were diagnosed with ADHD from age 7 years onwards (age of starting school). We calculated incidence ratios to assess the inter-relations between relative age within the school year, age at ADHD diagnosis, and year of diagnosis (1998-2003 vs 2004-11).

FINDINGS

Between Jan 1, 1998, and Dec 31, 2011, 6136 children with ADHD were identified. Compared with the oldest children in the school year (ie, those born between January and April), the cumulative incidence of an ADHD diagnosis was greatest for the youngest children (ie, those born between September and December); for boys the incidence ratio was 1·26 (95% CI 1·18-1·35; p<0·0001) and for girls it was 1·31 (1·12-1·54; p=0·0007). The association between relative age and age at ADHD diagnosis reflected children diagnosed before age 10 years, and the strength of this association increased during recent years (2004-11). Thus, compared with children born between January and April, for those born between May and August, the ADHD incidence ratio was 1·37 (95% CI 1·24-1·53; p<0·0001) and for those born between September and December, the incidence ratio was 1·64 (1·48-1·81; p<0·0001). The relative age effect was not accounted for by comorbid disorders such as CD, ODD, or LD.

INTERPRETATION

In a health service system with low prescribing rates for ADHD, a younger relative age is associated with an increased likelihood of receiving a clinical diagnosis of ADHD. This effect has increased in recent years. Teachers, parents, and clinicians should take relative age into account when considering the possibility of ADHD in a child or encountering a child with a pre-existing diagnosis.

FUNDING

Academy of Finland, Finnish Medical Foundation, Orion Pharma Foundation, Finnish Cultural Foundation.

Examining the psychological and social impact of relative age in primary school children: a cross-sectional survey

BACKGROUND

A number of studies demonstrate that children who are younger within their school year have poorer academic attainment and are more likely to have special educational needs. Few, however, have considered the impact relative age may have on child mental health, behaviour and happiness in school.

METHODS

This paper utilized data from the Supporting Teachers and Children in Schools study (2075 pupils aged 5 to 9 years from 80 primary schools) to explore the relationship among relative age, behaviour and happiness in school. Behavioural and emotional development was assessed by using the teacher-reported and parent-reported Strengths and Difficulties Questionnaire and the Pupil Behaviour Questionnaire. Children's happiness within school was assessed by using the How I Feel About My School Questionnaire.

RESULTS

Relatively younger children had higher Total Difficulties scores on the Strengths and Difficulties Questionnaire than their peers. There was a mean increase per 30-day decrease in relative age of 0.09 (95% CI: 0.03 to 0.16; p = 0.007) in teacher-reported and 0.08 (0.001 to 0.16; p = 0.05) in parent-reported scores. There was little evidence of a relationship between relative age and children's behaviour and happiness in school.

CONCLUSIONS

For children with complex difficulties, being relatively young for their school year may be an additional stressor that may undermine mental health.

Relative age effects in the Movement Assessment Battery for Children-2: age banding and scoring errors

AIM

The Movement Assessment Battery for Children-2 (MABC-2) uses age-grouped scoring, which will result in relative motor functioning being overestimated for some children and underestimated for others. In this paper, we measure these errors and discuss their consequences.

METHOD

We pool data from two validation studies to obtain a sample of 278 children assessed with the MABC-2 (mean (SD) age: 5 years, 0 months (9.6 months); 142 female). We used regression to measure the association between standard score and relative age, and used these results to estimate misclassification rates at the MABC-2's recommended thresholds.

RESULTS

Movement Assessment Battery for Children-2 scores were distributed as expected (mean (SD) = 10.4 (2.8)). We estimated that the standard score varied by 2.76 units (0.92 SDs) per year of relative age. Depending on threshold and age bandwidth, this implies overall misclassification rates from 9% to 23%.

INTERPRETATION

Relative age differences in MABC-2 scores led to substantial systematic error for young children. These errors can affect MABC-2 validity, longitudinal stability and agreement with other tools, which may reduce the appropriateness of care offered to children. Scoring approaches that may reduce or eliminate these errors are outlined.

ADHD in school-aged youth: Management and special treatment considerations in the primary care setting

Attention-deficit/hyperactivity disorder is considered one of the most common neurodevelopmental disorders of childhood. Primary care providers are in the unique position of providing comprehensive care-routine care, well child visits, immunizations, and other healthcare needs-to a majority of children and adolescents with attention-deficit/hyperactivity disorder. As such, primary care providers are pivotal in the diagnosis, management, and treatment of this population. This article will address special treatment considerations to aid in the management of attention-deficit/hyperactivity disorder in the primary care setting, including substance use disorders and diversion, cardiac issues and stimulant medication, medication holidays and follow-up monitoring. The database of PubMed was searched using keywords that included attention-deficit/hyperactivity disorder, children, prevalence, medication holidays, safety, cardiovascular, cardiac, blood pressure, substance use, diversion, adverse drug reactions; inclusion dates were January 1, 2011 to September 30, 2015.

Antidepressant Use in Pregnancy and the Risk of Attention Deficit with or without Hyperactivity Disorder in Children

BACKGROUND

The association between antidepressant (AD) use during pregnancy and the risk of attention deficit with or without hyperactivity disorder (ADHD) in children is debated. We investigated the risk of ADHD associated with overall and class-specific antidepressant exposure in utero.

METHODS

We designed a register-based cohort study using the Quebec Pregnancy/Children Cohort (QPC). A total of 144 406 singleton full-term live-born from 1998 to 2009 were included. Cox proportional hazards regression models were used to estimate unadjusted and adjusted hazard ratio with 95% confidence interval (CI).

RESULTS

During 542 897 person-years of follow-up, 4564 (3.2%) infants were identified with ADHD. The mean age at first ADHD diagnosis was 6.3 ± 2.3 years (range 0-11 years), and the mean age at first ADHD medication use was 7.0 ± 1.5 years. Adjusting for potential confounders, including maternal history of depression/anxiety and ADHD, AD use during the 2nd or 3rd trimester of pregnancy was associated with an increased risk of (HR 1.3, 95% CI 1.0, 1.6; 134 exposed cases). More specifically, tricyclic use was associated with an increased risk of ADHD (HR 1.8, 95% CI 1.0, 3.1; 16 exposed cases); SSRI and SNRI use were not associated with increased ADHD risk.

CONCLUSION

This study suggests that AD use during the 2nd and 3rd trimester of pregnancy, specifically tricyclics, is an independent risk factor for ADHD in children above and beyond the risk associated with maternal depression/anxiety or ADHD. However, residual confounding by indication severity could not be completely ruled out.

ADHD treatment and diagnosis in relation to children's birth month: Nationwide cohort study from Norway

BACKGROUND

Studies from several countries have reported that children youngest in grade are at higher risk of attention-deficit/hyperactivity disorder (ADHD) diagnosis and treatment. Norwegian children start school the year they turn six, making children born in December youngest in their grade. We used data on medication, specialist healthcare diagnoses, and primary healthcare diagnoses from national registers to investigate associations between birth month and ADHD.

METHODS

All children born in Norway between 1998 and 2006 ( N=509,827) were followed from age six until 31 December 2014. We estimated hazard ratios for ADHD medication and diagnoses by birth month in Cox proportional-hazards models. We compared risk among siblings to control for potentially confounding socioeconomic factors, and assessed risk of receiving ADHD medication by birth month while attending different grades in cross-sectional time-series analyses.

RESULTS

At end of follow-up, 5.3% of boys born in October-December had received ADHD medication, compared with 3.7% of boys born in January-March. Corresponding numbers for girls were 2.2% and 1.3%, respectively. The adjusted hazard ratio for ADHD medication for children born in October-December (reference: January-March) was 1.4 (95% confidence interval: 1.4-1.5) for boys and 1.8 (1.7-2.0) for girls. Analyses with diagnoses as outcome showed consistent results, and analyses restricted to siblings within the study population also supported the findings. Analysis by grade revealed an increased risk for children born late in the year from grade 3 onwards, with most marked differences in higher grades.

CONCLUSIONS

Children youngest in grade had the highest risk of receiving ADHD treatment. Differences were most marked among older children.

Overdiagnosis of mental disorders in children and adolescents (in developed countries)

During the past 50 years, health insurance providers and national registers of mental health regularly report significant increases in the number of mental disorder diagnoses in children and adolescents. However, epidemiological studies show mixed effects of time trends of prevalence of mental disorders. Overdiagnosis in clinical practice rather than an actual increase is assumed to be the cause for this situation. We conducted a systematic literature search on the topic of overdiagnosis of mental disorders in children and adolescents. Most reviewed studies suggest that misdiagnosis does occur; however, only one study was able to examine overdiagnosis in child and adolescent mental disorders from a methodological point-of-view. This study found significant evidence of overdiagnosis of attention-deficit/hyperactivity disorder. In the second part of this paper, we summarize findings concerning diagnostician, informant and child/adolescent characteristics, as well as factors concerning diagnostic criteria and the health care system that can lead to mistakes in the routine diagnostic process resulting in misdiagnoses. These include the use of heuristics instead of data-based decisions by diagnosticians, misleading information by caregivers, ambiguity in symptom description relating to classification systems, as well as constraints in most health systems to assign a diagnosis in order to approve and reimburse treatment. To avoid misdiagnosis, standardized procedures as well as continued education of diagnosticians working with children and adolescents suffering from a mental disorder are needed.

Association Between Age of Beginning Primary School and Attention Deficit Hyperactivity Disorder

OBJECTIVE

In April 2012, the Turkish national education system was modified, and the compulsory school age of entry (first grade) was redefined as a minimum of 60 months and a maximum of 66 months (replacing the former minimum criterion of 72 months). In this study, we hypothesized that students starting school before 72 months (the previous age standard for the first grade) may experience (1) a greater number of symptoms of attention deficit hyperactivity disorder (ADHD) and (2) lower functioning in social, behavioral, and academic domains.

METHOD

We performed a cross-sectional community-based study in the first and second grades of all primary schools (4356 students) located in the Kadıköy county of Istanbul, Turkey. Teachers completed Swanson, Nolan, and Pelham version IV and Conners' Teacher's report forms for symptoms of ADHD, the Perceived Competence Scale for functioning, and a sociodemographic questionnaire.

RESULTS

Among first graders, the group that began primary school before the age of 72 months had a higher ADHD prevalence than both of the groups that began primary school between the ages of 72 to 77 months and 78 to 83 months (p < .001 for both groups). ADHD symptoms diminished and academic, social, and behavioral functioning improved with age for the first and second grade students.

CONCLUSION

The probability of displaying ADHD symptoms (and caseness) is greater among the "earlier" beginners, whereas the "conventional" classmates exhibited better academic, social, and behavioral functioning.

Relative Immaturity in Childhood and Attention-Deficit/Hyperactivity Disorder Symptoms From Childhood to Early Adulthood: Exploring Genetic and Environmental Overlap Across Development

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) has been linked to immaturity relative to peers in childhood, yet it is unclear how such immaturity is associated with ADHD across development. This longitudinal twin study examined the genetic and environmental contributions to the association between parents' perception of their child's immaturity relative to peers (RI) in childhood and ADHD symptoms across development.

METHOD

1,302 twin pairs from the Swedish Twin Study of Child and Adolescent Development were followed prospectively from childhood to early adulthood. Parent ratings of RI were collected at 8 to 9 years and parent and self-ratings of ADHD symptoms were collected at 8 to 9, 13 to 14, 16 to 17, and 19 to 20 years using the Child Behavior Checklist Attention Problems scale. In addition, ADHD symptoms corresponding to DSM criteria were used for sensitivity analysis. Analyses were conducted using longitudinal structural equation modeling with multiple raters.

RESULTS

RI-related etiologic factors, predominantly influenced by genes, explained 10-14% of the variance in ADHD symptoms from 8 to 9 up to 16 to 17 years. The influence of these RI-related factors on ADHD symptoms attenuated to 4% by 19 to 20 years of age. The remaining variance in ADHD symptoms was primarily explained by genetic factors independent of RI, which remained relatively stable across development, explaining 19% to 30% of the variance in ADHD symptoms from 13 to 14 up to 19 to 20 years.

CONCLUSION

The results show that RI is significantly associated with ADHD symptoms, particularly during childhood and adolescence, and that the association is primarily explained by a shared genetic liability. Nevertheless, the magnitude of associations across development was modest, highlighting that RI is merely one aspect contributing to the complex etiology of ADHD symptoms.

Influence of Relative Age on Diagnosis and Treatment of Attention-Deficit Hyperactivity Disorder in Taiwanese Children

OBJECTIVE

To determine the potential influence of relative age on the diagnosis and treatment of attention-deficit hyperactivity disorder (ADHD), especially in reference to an Asian country.

STUDY DESIGN

A total of 378 881 subjects aged 4-17 years during the study period (September 1, 1997 to August 31, 2011) were enrolled in our study from the Taiwan National Health Insurance Research Database. Logistic regression analysis was used to examine the likelihood of receiving ADHD diagnosis and treatment for those who were born in August (the youngest) compared with those who were born in September (the oldest).

RESULTS

Both boys and girls born in August had a higher risk of being diagnosed with ADHD (OR 1.63, 95% CI 1.45-1.84; OR 1.71, 95% CI 1.36-2.15) and receiving ADHD medication (OR 1.76, 95% CI 1.53-2.02; OR 1.65, 95% CI 1.26-2.18) than those born in September. Sensitivity tests conducted over different periods revealed consistent findings.

CONCLUSIONS

Relative age, as an indicator of neurocognitive maturity, is crucial in the risk of being diagnosed with ADHD and receiving ADHD medication among children and adolescents. Our findings emphasize the importance of considering the age of a child within a grade when diagnosing ADHD and prescribing medication for treating ADHD.

Stimulant use for ADHD and relative age in class among children in Israel

BACKGROUND

Diagnosis of children with attention-deficit/hyperactivity disorder (ADHD) is increasing. The present study sought to identify characteristics and medication treatment patterns of children with ADHD and compare them by relative age in class, sex, ethnicity, family size, sibling order, and other socioeconomic status, as well as find trends in disparity of pharmacotherapy.

METHODS

This study was based on data from 1 013 149 Clalit Health Services members aged 6-17 years during 2006-2011. Centrally acting sympathomimetic drug purchases were compared according to children's estimated relative age in class; youngest third (born August to November), middle third (born April to July), and oldest third (born December to March). Treatment trends were determined and compared according to sociodemographic and family-related factors.

RESULTS

The overall prevalence of stimulant use in the population was 2.6% in 2006 and 4.9% in 2011. The annual incidence of stimulant use increased from 0.75% to 1.36%, rising more sharply among children in the older age groups (≥12) than among younger ones. Moreover, the youngest third of children in class was more likely to use medication than the oldest third (risk ratio (RR) 1.17, confidence interval (CI) 1.12-1.23) or the middle third (RR 1.06, CI 1.01-1.11). Of the different ethnic sectors, incidence of stimulant use was highest among general Jewish (1.8% in 2011) and lowest among Arabs (0.37% in 2011).

CONCLUSIONS

The use of stimulant medication is growing among children in Israel. Although the overall use does not exceed the estimated prevalence of ADHD among children, the appropriateness of prescribing to the Israeli pediatric population, especially to the youngest children in class, may be questionable. Copyright © 2016 John Wiley & Sons, Ltd.

Younger children experience lower levels of language competence and academic progress in the first year of school: evidence from a population study

BACKGROUND

The youngest children in an academic year are reported to be educationally disadvantaged and overrepresented in referrals to clinical services. In this study we investigate for the first time whether these disadvantages are indicative of a mismatch between language competence at school entry and the academic demands of the classroom.

METHODS

We recruited a population sample of 7,267 children aged 4 years 9 months to 5 years 10 months attending state-maintained reception classrooms in Surrey, England. Teacher ratings on the Children's Communication Checklist-Short (CCC-S), a measure of language competence, the Strengths and Difficulties Questionnaire-Total Difficulties Score (SDQ), a measure of behavioural problems, and the Early Years Foundation Stage Profile (EYFSP), a measure of academic attainment, were obtained at the end of the reception year.

RESULTS

The youngest children were rated by teachers as having more language deficits, behaviour problems, and poorer academic progress at the end of the school year. Language deficits were highly associated with behaviour problems; adjusted odds ratio 8.70, 95% CI [7.25-10.45]. Only 4.8% of children with teacher-rated language deficits and 1.3% of those with co-occurring language and behaviour difficulties obtained a 'Good Level of Development' on the EYFSP. While age predicted unique variance in academic attainment (1%), language competence was the largest associate of academic achievement (19%).

CONCLUSION

The youngest children starting school have relatively immature language and behaviour skills and many are not yet ready to meet the academic and social demands of the classroom. At a population level, developing oral language skills and/or ensuring academic targets reflect developmental capacity could substantially reduce the numbers of children requiring specialist clinical services in later years.

Relative Age Effects in Dutch Adolescents: Concurrent and Prospective Analyses

The literature on relative age position effects is rather inconsistent. In this study we examined intra-classroom age position (or relative age) effects on Dutch adolescents' school progress and performance (as rated by teachers), physical development, temperamental development (fear and frustration), and depressive symptoms, all adjusted for age at the time of measurement. Data were derived from three waves of Tracking Adolescents' Individuals Lives Survey (TRAILS) of 2230 Dutch adolescents (baseline mean age 11.1, SD = 0.6, 51% girls). Albeit relative age predicted school progress (grade retention ORs = 0.83 for each month, skipped grade OR = 1.47, both p<.001), our key observation is the absence of substantial developmental differences as a result of relative age position in Dutch adolescents with a normative school trajectory, in contrast to most literature. For adolescents who had repeated a grade inverse relative age effects were observed, in terms of physical development and school performance, as well as on depressive symptoms, favoring the relatively young. Cross-cultural differences in relative age effect may be partly explained by the decision threshold for grade retention.

Misdiagnosis of attention deficit hyperactivity disorder: 'Normal behaviour' and relative maturity

Attention deficit hyperactivity disorder (ADHD) is one of the most frequently diagnosed disorders in children, yet it remains poorly understood. Substantial controversy exists regarding correct diagnosis of ADHD, and areas of subjectivity in diagnosis have been identified. Concerns for appropriate diagnosis are critical in terms of children's educational outcomes, as well as health concerns associated with the use and potential overuse of stimulant medications. There exists a relative-age effect in which children who are relatively younger than their peers and born closest to the school start age cut-off are more frequently diagnosed and treated for ADHD. Additionally, substantial variation exists in ADHD diagnosis between boys and girls, with boys often presenting with more stereotypical symptoms. Both the relative-age effect and variation in sex diagnosis, as well as the challenges of early preschool diagnosis, emphasize the importance of considering relative maturity in ADHD diagnosis of children. Implications and knowledge translation strategies for practitioners, parents and the education system are presented.

What we do not know about ADHD… yet

PURPOSE OF REVIEW

This article provides an overview of current controversies in attention-deficit/hyperactivity disorder (ADHD) research, with an emphasis on recent findings that are directly relevant to clinical practice.

RECENT FINDINGS

Over the past few years, a number of studies have added key evidence to ongoing debates about the epidemiology, nosology, and treatment of ADHD. Although the causes of the rising prevalence of ADHD in the USA are still not fully understood, recent research suggests that environmental factors and changes to the diagnostic criteria may have played a role. In addition, there continues to be controversy surrounding the clinical diagnosis of ADHD and newly recognized, related conditions such as sluggish cognitive tempo. Recent studies have also challenged previous assumptions about the long-term effects of stimulant treatment on growth, academic achievement, and substance use. Moreover, although most complementary and alternative therapies for ADHD appear to be ineffective, there is emerging evidence supporting the value of fatty acid supplementation. Although these findings are promising, more research is needed on all fronts.

SUMMARY

Although research has shed light on unanswered questions about the epidemiology, nosology, and treatment of ADHD, much is still not known. An understanding of the most important current controversies in ADHD research may aid pediatricians in clinical decision making and allow them to counsel patients more effectively.

Integration of an EEG biomarker with a clinician's ADHD evaluation

BACKGROUND

This study is the first to evaluate an assessment aid for attention-deficit/hyperactivity disorder (ADHD) according to both Class-I evidence standards of American Academy of Neurology and De Novo requirements of US Food and Drug Administration. The assessment aid involves a method to integrate an electroencephalographic (EEG) biomarker, theta/beta ratio (TBR), with a clinician's ADHD evaluation. The integration method is intended as a step to help improve certainty with criterion E (i.e., whether symptoms are better explained by another condition).

METHODS

To evaluate the assessment aid, investigators conducted a prospective, triple-blinded, 13-site, clinical cohort study. Comprehensive clinical evaluation data were obtained from 275 children and adolescents presenting with attentional and behavioral concerns. A qualified clinician at each site performed differential diagnosis. EEG was collected by separate teams. The reference standard was consensus diagnosis by an independent, multidisciplinary team (psychiatrist, psychologist, and neurodevelopmental pediatrician), which is well-suited to evaluate criterion E in a complex clinical population.

RESULTS

Of 209 patients meeting ADHD criteria per a site clinician's judgment, 93 were separately found by the multidisciplinary team to be less likely to meet criterion E, implying possible overdiagnosis by clinicians in 34% of the total clinical sample (93/275). Of those 93, 91% were also identified by EEG, showing a relatively lower TBR (85/93). Further, the integration method was in 97% agreement with the multidisciplinary team in the resolution of a clinician's uncertain cases (35/36). TBR showed statistical power specific to supporting certainty of criterion E per the multidisciplinary team (Cohen's d, 1.53). Patients with relatively lower TBR were more likely to have other conditions that could affect criterion E certainty (10 significant results; P ≤ 0.05). Integration of this information with a clinician's ADHD evaluation could help improve diagnostic accuracy from 61% to 88%.

CONCLUSIONS

The EEG-based assessment aid may help improve accuracy of ADHD diagnosis by supporting greater criterion E certainty.

Misclassification due to age grouping in measures of child development

PURPOSE

Screens for developmental delay generally provide a set of norms for different age groups. Development varies continuously with age, however, and applying a single criterion for an age range will inevitably produce misclassifications. In this report, we estimate the resulting error rate for one example: the cognitive subscale of the Bayley Scales of Infant and Toddler Development (BSID-III).

DESIGN

Data come from a general population sample of 594 children (305 male) aged 1 month to 42.5 months who received the BSID-III as part of a validation study. We used regression models to estimate the mean and variance of the cognitive subscale as a function of age. We then used these results to generate a dataset of one million simulated participants and compared their status before and after division into age groups. Finally, we applied broader age bands used in two other instruments and explored likely validity limitations when different instruments are compared.

RESULTS

When BSID-III age groups are used, 15% of cases are missed and 15% of apparent cases are false positives. Wider age groups produced error rates from 27% to 46%. Comparison of different age groups suggests that sensitivity in validation studies would be limited, under certain assumptions, to 70% or less.

IMPLICATIONS

The use of age groups produces a large number of misclassifications. Although affected children will usually be close to the threshold, this may lead to misreferrals. Results may help to explain the poor measured agreement of development screens. Scoring methods that treat child age as continuous would improve instrument accuracy.

Klinische Diagnostik der ADHS im Vorschulalter

Die Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (ADHS) ist eine der häufigsten psychischen Störungen des Kindes- und Jugendalters und weist negative Folgen für die Betroffenen und das nähere Umfeld auf. Eine frühzeitige Erkennung von ADHS wäre für die Planung von Präventivmaßnahmen sinnvoll, um langfristige Folgen zu vermeiden. Ziel des Überblickartikels ist eine Bestandsaufnahme über die verfügbaren Fragebögen und klinischen Interviews zur Diagnostik von ADHS im Vorschulalter (3–5 Jahre). Es werden für den deutschen und den internationalen Raum verfügbare Verfahren verglichen und kritisch bewertet. Die Bedeutung von Fragebögen und klinischen Interviews im Rahmen einer ADHS-Diagnostik wird diskutiert.

Assessment and treatment of attention-deficit/hyperactivity disorder: part 1

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood. Affecting up to 10% of children in the United States, it is one of the most frequently encountered conditions in primary care. ADHD is a chronic condition, and a significant number of youth continue to show impairment into adulthood. Given the national shortage of specialty mental health providers, primary care providers need to feel comfortable and competent in screening, assessing, and managing ADHD. Successful assessment for this disorder involves regular screening for symptoms of inattention, impulsivity, and hyperactivity during office visits. If ADHD is suspected, a more comprehensive evaluation utilizing standardized rating scales and multiple informants (eg, parents and teachers) is recommended to confirm the diagnosis and guide initial treatment interventions.

The pharmacological and non-pharmacological treatment of attention deficit hyperactivity disorder in children and adolescents: protocol for a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders of children and adolescents, with a significant impact on health services and the community in terms of economic and social burdens. The objective of this systematic review will be to evaluate the comparative efficacy and safety of pharmacological and non-pharmacological treatments in children and adolescents with ADHD.

METHODS

Searches involving PubMed/MEDLINE and the Cochrane Database of Systematic Reviews will be used to identify related systematic reviews and relevant randomized trials. Search results will be supplemented by reports from the regulatory and health technology agencies, clinical trials registers and by data requested from trialists and/or pharmaceutical companies. We will consider studies evaluating pharmacological interventions (e.g. stimulants, non-stimulants, antidepressants), psychological interventions (e.g. behavioural interventions, cognitive training and neurofeedback) and complementary and alternative medicine interventions (e.g. dietary interventions, supplement with fatty acids, vitamins, minerals, aminoacids, herbal treatment, homeopathy, and mind-body interventions including massage, chiropractic, acupuncture, yoga, meditation, Tai chi). Eligible control conditions will be placebo, waitlist, no treatment and usual care. Randomized controlled trials of a minimum of 3 weeks duration will be included. The primary outcomes of interest will be the proportion of patients who responded to treatment and who dropped out of the allocated treatment, respectively. Secondary outcomes will include treatment discontinuation due to adverse events, as well as the occurrences of serious adverse events and specific adverse events (decreased weight, anorexia, insomnia and sleep disturbances, anxiety, syncope and cardiovascular events). Two reviewers will independently screen references identified by the literature search, as well as potentially relevant full-text articles in duplicate. Data will be abstracted and risk of bias will be appraised by two team members independently. Conflicts at all levels of screening and abstraction will be resolved through discussion. Random-effects pairwise meta-analyses and Bayesian network meta-analyses will be conducted where appropriate.

DISCUSSION

This systematic review and network meta-analysis will compare the efficacy and safety of treatments used for ADHD in children and adolescents. The findings will assist patients, clinicians and healthcare providers to make evidence-based decisions regarding treatment selection.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014015008 .

Overdiagnosis: how our compulsion for diagnosis may be harming children

Overdiagnosis occurs when a true abnormality is discovered, but detection of that abnormality does not benefit the patient. It should be distinguished from misdiagnosis, in which the diagnosis is inaccurate, and it is not synonymous with overtreatment or overuse, in which excess medication or procedures are provided to patients for both correct and incorrect diagnoses. Overdiagnosis for adult conditions has gained a great deal of recognition over the last few years, led by realizations that certain screening initiatives, such as those for breast and prostate cancer, may be harming the very people they were designed to protect. In the fall of 2014, the second international Preventing Overdiagnosis Conference will be held, and the British Medical Journal will produce an overdiagnosis-themed journal issue. However, overdiagnosis in children has been less well described. This special article seeks to raise awareness of the possibility of overdiagnosis in pediatrics, suggesting that overdiagnosis may affect commonly diagnosed conditions such as attention-deficit/hyperactivity disorder, bacteremia, food allergy, hyperbilirubinemia, obstructive sleep apnea, and urinary tract infection. Through these and other examples, we discuss why overdiagnosis occurs and how it may be harming children. Additionally, we consider research and education strategies, with the goal to better elucidate pediatric overdiagnosis and mitigate its influence.

Children's relative age in class and use of medication for ADHD: a Danish Nationwide Study

BACKGROUND

Previous studies from North America and Iceland have shown that the youngest children within a grade are up to twice as likely to be diagnosed and treated for attention-deficit/hyperactivity disorder (ADHD) compared with their older classmates. We aimed to investigate whether younger age in class is associated with an increased probability of being prescribed medication for ADHD among school-aged children in Denmark.

METHODS

We followed all Danish children between 2000 and 2012 from 1st through 6th grade (7-12 years). Among children who started school on their age-assigned grade level, we estimated the prevalence proportion ratio (PPR) of receiving ADHD medication between the youngest children in class (born in October-December) and the oldest in class (born in January-March), specified by grade level, calendar year and gender. As a sensitivity analysis, we added children not on their age-assigned grade level to the main calculations.

RESULTS

We identified 932,032 eligible children for the main analysis, of whom 17.3% were among the youngest and 26.5% among the oldest in class. In total, 1.2% eligible children filled at least one prescription for ADHD medication in 2000-2012. The average PPR over the study period was 1.08 (95% CI, 1.04-1.12) and remained stable across subgroups and sensitivity analyses. Overall, 40% of children born October-December had entered school a year after their age-assigned grade level.

CONCLUSIONS

Contrary to previous study results, we observed almost no relative age effect on medication use for ADHD among children in Denmark. We postulate that this may be due to the high proportion of relatively young children held back by 1 year in the Danish school system and/or a generally low prevalence of ADHD medication use in the country.

Common Danish standards in prescribing medication for children and adolescents with ADHD

Assessing whether symptoms of attention-deficit hyperactivity disorder (ADHD) in children are age-inappropriate is essential. Hence, comparing children within one school grade is problematic and the risk of applying relative standards is inherent. Being young-for-grade increases the likelihood of receiving medication in countries with high prevalence of ADHD medication. We test the same hypothesis in a cohort of 418,396 children and find no difference between children who are young-for-grade and old-for-grade. The Danish system, with its restrictive approach to medication and clear diagnostic guidelines seems to have avoided a systematic bias of ADHD medication in young children reported in other countries.

Competent psychopharmacology

There is little doubt that undergraduate and post-graduate training of physicians, pharmacists, and nurses is insufficient to prepare them to use psychotropics safely and effectively, especially in the context of their expanded off-label uses. Therefore, the development of competencies in psychotropic prescribing needs to be approached as a long-term, practice-based learning commitment. Proposed are the abilities and knowledge components necessary for safe and effective use of psychotropics. Typical challenges in prescribing for chronic and recurrent illnesses include highly variable responses and tolerability, drug interactions, and adverse effects that can be serious, irreversible, and even fatal. Prescribing psychotropics is further complicated by negative public and professional reports and growing patient concerns about the quality of care, and questions about the efficacy, safety, and addictive risks of psychotropics. Increased efforts are needed to enhance clinical training and knowledge in psychopharmacology among trainees and practising clinicians, with more comprehensive and sustained attention to the assessment of individual patients, and greater reliance on patient education and collaboration. Improved competence in psychotropic prescribing should lead to more informed, thoughtful, and better-targeted applications as one component of more comprehensive clinical care.

Relative immaturity and ADHD: findings from nationwide registers, parent- and self-reports

BACKGROUND

We addressed if immaturity relative to peers reflected in birth month increases the likelihood of ADHD diagnosis and treatment.

METHODS

We linked nationwide Patient and Prescribed Drug Registers and used prospective cohort and nested case-control designs to study 6-69 year-old individuals in Sweden from July 2005 to December 2009 (Cohort 1). Cohort 1 included 56,263 individuals diagnosed with ADHD or ever used prescribed ADHD-specific medication. Complementary population-representative cohorts provided DSM-IV ADHD symptom ratings; parent-reported for 10,760 9-year-old twins born 1995-2000 from the CATSS study (Cohort 2) and self-reported for 6,970 adult twins age 20-47 years born 1959-1970 from the STAGE study (Cohort 3). We calculated odds ratios (OR:s) for ADHD across age for individuals born in November/December compared to January/February (Cohort 1). ADHD symptoms in Cohorts 2 and 3 were studied as a function of calendar birth month.

RESULTS

ADHD diagnoses and medication treatment were both significantly more common in individuals born in November/December versus January/February; peaking at ages 6 (OR: 1.8; 95% CI: 1.5-2.2) and 7 years (OR: 1.6; 95% CI: 1.3-1.8) in the Patient and Prescribed Drug Registers, respectively. We found no corresponding differences in parent- or self-reported ADHD symptoms by calendar birth month.

CONCLUSION

Relative immaturity compared to class mates might contribute to ADHD diagnosis and pharmacotherapy despite absence of parallel findings in reported ADHD symptom loads by relative immaturity. Increased clinical awareness of this phenomenon may be warranted to decrease risk for imprecise diagnostics and treatment. We speculate that flexibility regarding age at school start according to individual maturity could reduce developmentally inappropriate demands on children and improve the precision of ADHD diagnostic practice and pharmacological treatment.

[From brain imaging to good teaching? implicating from neuroscience for research on learning and instruction]

Psychiatric disorders in childhood and adolescence, in particular attention deficit disorder or specific learning disorders like developmental dyslexia and developmental dyscalculia, affect academic performance and learning at school. Recent advances in neuroscientific research have incited an intensive debate both in the general public and in the field of educational and instructional science as well as to whether and to what extent these new findings in the field of neuroscience might be of importance for school-related learning and instruction. In this review, we first summarize neuroscientific findings related to the development of attention, working memory and executive functions in typically developing children and then evaluate their relevance for school-related learning. We present an overview of neuroimaging studies of specific learning disabilities such as developmental dyslexia and developmental dyscalculia, and critically discuss their practical implications for educational and teaching practice, teacher training, early diagnosis as well as prevention and disorder-specific therapy. We conclude that the new interdisciplinary field of neuroeducation cannot be expected to provide direct innovative educational applications (e.g., teaching methods). Rather, the future potential of neuroscience lies in creating a deeper understanding of the underlying cognitive mechanisms and pathomechanisms of learning processes and learning disorders.

Exploring five common assumptions on Attention Deficit Hyperactivity Disorder

The number of children diagnosed with attention deficit hyperactivity disorder (ADHD) and treated with medication is steadily increasing. The aim of this paper was to critically discuss five debatable assumptions on ADHD that may explain these trends to some extent. These are that ADHD (i) causes deviant behaviour, (ii) is a disease, (iii) is chronic and (iv) is best treated by medication and (v) that classification should precede treatment.

CONCLUSION

We argue that ADHD is not a disease, not the cause of deviant behaviour and in most cases not chronic. Treatment for attention and hyperactivity problems could start with psychosocial interventions and without a diagnostic label. A stepped diagnosis approach may reduce overdiagnosis without risking undertreatment.

Addressing the problem of ADHD medication as neuroenhancements

The prevalence of attention deficit hyperactivity disorder (ADHD) diagnoses is rising. ADHD is closely linked to its treatment with medications such as methylphenidate and amphetamines, which have popular appeal as neuroenhancement drugs by persons without a neurological disorder. The three main reasons for the increase in ADHD medication demand, production, and consumption are a) the inclusion of milder ADHD diagnoses; b) the vast marketing of ADHD medications by the pharmaceutical industry; and c) the illegal diversion of controlled ADHD medication to consumers seeking stimulants as neuroenhancements. Rapidly rising rates of any neurological disorder - especially a behaviorly-defined disorder closely linked to potent medications currently prescribed to more than 5% of the population - deserves ongoing scrutiny. Major social and ethical problems arise from vague-symptom medicalization, neurological disorder trivialization, medication overuse, and controlled substances diversion to healthy persons for nonmedical purposes. We argue against the 'spectrumization' of ADHD in an effort to curtail further diagnosis creep.

Medical treatment of children and youths with attention-deficit/hyperactivity disorder (ADHD): a Norwegian Prescription Registry Based Study

OBJECTIVES

Attention-deficit/hyperactivity disorder (ADHD) is a lifelong neurological condition with a profound effect on quality of life. Prescription databases may document pattern of use. In this study we aimed to explore the use in Norway employing such a database.

METHODS

All prescriptions on drugs for the treatment of ADHD between 2004 and 2011, as registered in the Norwegian Prescription Database (NPD) were analyzed. The following drugs were included: Amphetamine, dexamphetamine, methylphenidate and atomoxetine. In-hospital drug administration was excluded. Numbers of users per 1,000 inhabitants were calculated according to gender, age and residence. A sub-analysis compared users born in January-June with those born in July-December. Drug costs were calculated and converted into Euros (€ 1 = N.kr 7.4540).

RESULTS

Drugs for the treatment of ADHD was significantly more often prescribed in northern Norway than in any other Norwegian health region (P < 0.001). Within the northern region, Nordland County was the "culprit" (P < 0.02). Compared to Norwegian figures, significantly more females (aged 10-19 years) were treated in northern Norway [male/female ratios 3:1 and 2.2:1 (P < 0.01)] and especially in Nordland County (ratio 2.1:1). The subanalysis did not indicate a northern overtreatment of those being a younger group in their grade. The annual drug cost per user in Norway was € 919.

CONCLUSIONS

The prescription rate was significantly higher in northern Norway and Nordland County was the culprit. A prescription database may be a tool for monitoring the national use of these drugs.

No link between date of birth and ADHD symptoms in adults

OBJECTIVE

Research has highlighted several negative consequences for individuals born in the later part of the academic year, including increased likelihood of being diagnosed with learning disabilities. In this study, we considered whether birthdate predicted ADHD symptomatology using two well known mechanisms, the relative age effect (RAE) and the season of birth effect (SOBE).

METHODS

Study participants completed two ADHD measures: Conners Adult ADHD Rating Scales (CAARS) and the Wender Utah Rating Scale (WURS).

RESULTS

There were gender effects in the WURS data indicating that males scored higher than females on ADHD symptoms as well as a significant interaction in the CAARS data to support differential patterns among males and females.

CONCLUSION

Overall, results did not support a RAE or SOBE among males or females. Possible reasons for these findings and their implications are discussed.

Expanding disease definitions in guidelines and expert panel ties to industry: a cross-sectional study of common conditions in the United States

BACKGROUND

Financial ties between health professionals and industry may unduly influence professional judgments and some researchers have suggested that widening disease definitions may be one driver of over-diagnosis, bringing potentially unnecessary labeling and harm. We aimed to identify guidelines in which disease definitions were changed, to assess whether any proposed changes would increase the numbers of individuals considered to have the disease, whether potential harms of expanding disease definitions were investigated, and the extent of members' industry ties.

METHODS AND FINDINGS

We undertook a cross-sectional study of the most recent publication between 2000 and 2013 from national and international guideline panels making decisions about definitions or diagnostic criteria for common conditions in the United States. We assessed whether proposed changes widened or narrowed disease definitions, rationales offered, mention of potential harms of those changes, and the nature and extent of disclosed ties between members and pharmaceutical or device companies. Of 16 publications on 14 common conditions, ten proposed changes widening and one narrowing definitions. For five, impact was unclear. Widening fell into three categories: creating "pre-disease"; lowering diagnostic thresholds; and proposing earlier or different diagnostic methods. Rationales included standardising diagnostic criteria and new evidence about risks for people previously considered to not have the disease. No publication included rigorous assessment of potential harms of proposed changes. Among 14 panels with disclosures, the average proportion of members with industry ties was 75%. Twelve were chaired by people with ties. For members with ties, the median number of companies to which they had ties was seven. Companies with ties to the highest proportions of members were active in the relevant therapeutic area. Limitations arise from reliance on only disclosed ties, and exclusion of conditions too broad to enable analysis of single panel publications.

CONCLUSIONS

For the common conditions studied, a majority of panels proposed changes to disease definitions that increased the number of individuals considered to have the disease, none reported rigorous assessment of potential harms of that widening, and most had a majority of members disclosing financial ties to pharmaceutical companies. Please see later in the article for the Editors' Summary.