TABLE 1

Demographic Characteristics of the NI/FT Cohort

VariableOverall Cohort (N = 1070)
Age at entry into the cohort, y
 1259 (24.2)
 1–5342 (32.0)
 6–12278 (26.0)
 13–18191 (17.9)
Male596 (55.7)
Median household income, $
 <30 00077 (7.2)
 30 001–39 999404 (37.8)
 40 000–49 999285 (26.6)
 50 000–59 999125 (11.7)
 ≥60 000179 (16.7)
Neurologic diagnoses (ICD-9 code/range)a
 Epilepsy and recurrent seizures (345)526 (49.2)
 Congenital anomalies (740–759)511 (47.8)
 Infantile cerebral palsy (343)485 (45.3)
 Mental disorders (290–319)436 (40.7)
 Other disorders of the central nervous system (340–342, 344, 346–349)325 (30.4)
 Hereditary and degenerative diseases of the central nervous system (330–337)313 (29.3)
 Certain conditions originating in the perinatal period (760–779)231 (21.6)
 Presence of cerebrospinal fluid drainage device (V45.2)174 (16.3)
 Injury and poisoning (800–999)160 (15.0)
 Cerebrovascular disease (430–438)122 (11.4)
 Disorders of the peripheral nervous system (350–359)63 (5.9)
 Other metabolic disorders and immunity disorders (270–279)43 (4.0)
 Inflammatory diseases of the central nervous system (320–327)36 (3.4)
  • Data are presented as n (%). ICD-9, International Classification of Diseases, Ninth Revision.

  • a Patients can have multiple diagnosis codes.