Attention‐deficit/hyperactivity disorder in schoolchildren in Crete

Abstract

Aim: To explore the prevalence of attention‐deficit/hyperactivity disorder (ADHD) in 7‐y‐old child residents of Crete, Greece. Methods: The study combined information from both parents and teachers for 1708 elementary school children attending the first grade in 101 classes of 55 primary schools. A two‐stage screening process was employed, including the ADHD test and a rating scale of student behaviour. Parents completed the ADHD test and teachers the rating scale of student behaviour. Results: Both questionnaires were completed for 1285 (75.2%) children. Among them, 84 children (6.5%; 95% CI 5.2–7.9%) met the study criteria for ADHD. The estimated prevalence was 8.8% for boys (95% CI 6.6–11.0%) and 4.2% for girls (95% CI 2.6–5.7%). No significant differences were observed regarding urban, semi‐urban or rural residence. Conclusion: By using a combination screening procedure, both the ADHD prevalence among first‐grade schoolchildren in Crete and the gender differences in prevalence were found to be comparable to those reported from other countries. The methods used and the problems faced illustrate the challenges involved in conducting population‐based studies of ADHD.

Variations in prevalence of attention deficit hyperactivity disorder worldwide

“…Higher prevalence rates have been associated with lower socioeconomic status [23,27,33,42,51] and among urban as compared to rural residence [6], but no significant differences were observed regarding the place of residence in other studies [10,14,32,40,49]. Prevalence variations between different racial and ethnic groups have not been adequately examined.…”

“…Out of the 39 studies, only 10 [10,20,25,33,35,36,42,45,49,53] were based on information from two settings and reported prevalence rates from 2.2 to 16.1%. Four of these studies [10,33,35,53] used DSM-III-R criteria and the remaining six [20,25,36,42,45,49] Definition of the disorder Modifications in the Diagnostic and Statistic Manual (DSM) of Psychiatric Disorders definition seemingly resulted in changes in the prevalence's rate of ADHD [6]. As already shown, ADHD prevalence was higher with DSM-IV criteria than with DSM-III-R, probably due to recognition of the disorder subtypes.…”

“…Parents are also valuable informants by having witnessed child's behaviour for several years in multiple settings. Contrary to earlier versions, DSM-IV diagnostic criteria require evidence of symptoms in two settings (e.g., school and home), and the use of multiple informants has become a basic epidemiological tool [49]. Thus the application of DSM-IV criteria to screen children in different settings may narrow the width of differences in prevalence estimations.…”

Prevalence of attention-deficit/hyperactivity disorder in Northern Cyprus

“…31 A review of the worldwide epidemiological studies on ADHD prevalence revealed a wide range of prevalence's, ranging from 0.9% to 20%. [8][9][10][11][12][13][14][15][16][17] Some studies have attributed the wide variation in ADHD prevalence to cultural and geographical factors, while many others have advocated that these discrepancies result from the diagnostic systems and methodology used, sources of information, and whether the diagnostic criteria (impairment and involving at least two domains) are required. 14 We used strict DSM-IV-TR diagnostic criteria for ADHD of symptoms being observed in at least two environments, a symptom onset before the age of 7 years, and a minimum symptom duration of 6 months.…”

“…[8][9][10][11][12][13][14][15][16][17] The prevalence of ADHD is lower in European countries compared with North America. 18 Thus, emphasis has been laid on cultural differences as a potential cause of the variation in ADHD prevalence.…”