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significant differences between those with sickle cell anemia who had not suffered a stroke and the siblingcontrols.Limitations. Some of the discrepancies between findings have been attributed to inconsistencies ofsubject selection and measurement techniques, a lack of consideration for potential covariates, and use ofunreliable measurement techniques (Brown et al., 1993).Implications. It appears that the sickle cell anemia, especially strokes resulting from the condition,jeopardize academic achievement. Sickle cell anemia affects more children than epilepsy, but thenumbers are still relatively small. However, similar to children with epilepsy, children with sickle cellanemia may be in need of special services and management that is appropriate for targeted, indicated,health services and mental health services in the school setting rather than for more universal programs.Sleep DisordersPrevalence. Sleep disorders in youth are attracting attention as sleep loss may be related to schoolschedules.Prevalence estimates for sleep disorders in youth are complicated by diagnostic criteria ranging from theneurological disorder of narcolepsy, to sleep disordered breathing, to life style-related sleep loss.Narcolepsy has been estimated to affect between four and 10 per 10,000 individuals with rare diagnosisamong youth younger than 18 (Dahl et al., 1994) Sleep disordered breathing is estimated to affectbetween 1% and 4% of children and youth but this estimate may also be compromised by failures indiagnosis (Kaemingk et al., 2003). Prevalence studies of lifestyle-related sleep loss among schoolchildren describe that more than 40% of Ohio eighth-graders reported sleeping seven hours or less onschool nights (Drake et al., 2003), middle and high school students in Maryland reported a mean of 6.7hours on weekdays (Eliasson et al., 2002) and students from Rhode Island reported an average of 7.7hours for students ages 13-14, and 7.25 hours for students age 16 (Wolfson A. R. & Carskadon, 1998).Sleep Disorders and Academic Performance. Studies examining the relationship between sleepdisordered breathing or obstructive sleep apnea found a negative relationship between the existence ofsleep abnormalities and school performance or memory. A retrospective study of a sample of 13- to 14-year-old children who ranked in the bottom quartile of their class, found that snoring between the ages of 2to 6 was reported more frequently by their parents compared to children in the upper quartile of the classwho were matched on age, gender, race, school and area of residence (Gozal & Pope Jr, 2001). Aprospective study among first-graders in the lowest 10 th percentile of their class from 32 public schoolsscreened for sleep-associated gas exchange abnormalities through a rigorous overnight protocol of pulseoximetry, pulse signal and transcutaneous carbon dioxide tension identified 54 children (8.1% of thesample) with obstructive sleep apnea (Gozal, 1998). Of these 54 children, 24 underwent surgical adenotonsillectomyand 30 were not treated. The 24 treated children experienced a significant increase inschool-reported academic grades from first to second grade compared to the non-treated children. Asimilar study screening children from Tucson schools, found 77 with an apnea/hypopnea index (AHI) > 5indicative five or more apneas or hypopneas per hour of sleep time found significant decreases in learningand memory among this group with AHI > 5 compared to 72 children with AHI < 5. Scores on verbal IQwere similar between the two groups (Kaemingk et al., 2003).Clinical studies also illustrate a relationship between sleep disorders and cognitive functioningrelated to academic performance. Among children with obstructive sleep apnea syndrome aged 5 to 12years from a pediatric sleep clinic population, small deficits in executive functioning/attention as comparedto normal children were found but these deficits were not related to disease severity. However, there weresome improvements in attention after adeno-tonsillectomy (Owens et al., 2000), suggesting a mechanismfor improvement of school performance. A clinical study of 5 children aged 11 to 14 years in a sleepdisorder clinic found amelioration of symptoms of heavy nocturnal snoring and daytime somnolence andsignificant improvements in number of arithmetic problems solved after tonsillectomy and/oradenoidectomy (Guilleminault et al., 1982). Children from a pediatric endocrinology clinic who wereE-13