Conducted a prospective study to estimate frequency of neurologic disorders in KelibiThe study used 3 sequential stages: (1) a pilot survey of 908 Ss to identify and correct any difficulties in implementing the survey, (2) a full-scale survey of 34,874 Ss, and (3) a control survey of 1,530 Ss to test global reliability of the full-scale survey. Better selection and training of interviewers during the control survey led to a higher positive predictive value with no modification in prevalence ratios of neurologic disorders. The control survey helped validate the full-scale survey datThe most frequent neurologic disorders were migraine, epilepsy, Bell's palsy, and essential tremor. Other associated conditions included intracranial infection, CNS tumor, cerebral palsy, mental retardation, and congenital or chromosomal malformations. Age-adjusted prevalence ratios are presented.