A screening instrument to measure the prevalence of neurological disability in resource-poor settings

Background: Very little is known about the prevalence of neurological morbidity in Africa. Much of this is due to the difficulty in performing epidemiological surveys in these settings. A screening instrument to measure neurological disease in resource-poor settings was designed by the World Health Organization in 1981, but several problems with it have subsequently been recognized. Methods: We created a new screening instrument that addressed problems with the original instrument identified by prior investigators, and that included questions to identify diseases of public health significance and broad neurological syndromes. This new instrument was tested in an outpatient setting in Moshi, Tanzania. We compared the sensitivity and specificity of the new instrument to the original 1981 WHO instrument. Results: We tested the survey on 128 participants. Of these, 63 had neurological diagnoses, 21 had pain-only diagnoses and 44 had no neurological diagnoses. The survey was well received by all the participants. A nonmedical interviewer was trained to administer and interpret a simple neurological examination without difficulty. The median time to administer the instrument was 13 min (interquartile range 10-17 min). The sensitivity of the new instrument improved that of the WHO instrument from 98.4 to 100%, but the difference was not statistically significant (p = 0.44). However, the specificity significantly improved from 29.2 to 61.0% (p = 0.001). Conclusions: We have developed a screening instrument to measure the prevalence of neurological morbidity in resource-poor settings. It was shown to be highly feasible, highly sensitive, and more specific than the existing WHO instrument.