A 25-Year Review of Cuba's Screening Program for Early Detection of Hearing Loss.

Introduction Early screening for hearing loss is currently recognized as an international healthcare standard. In Cuba, such a program was initiated in the capital, Havana, in 1983 and scaled up to national coverage in 1991. Objective Review the development of Cuba's national hearing screening program over the last 25 years (organizational structure, efficiency, coverage and impact on health), and the science and technology developed to sustain it. Intervention The program was organized in two steps: Step 1-clinical selection of children at different stages of development with multiple high-risk registers; Step 2-referral to territorial, hospitalbased centers for auditory brainstem evoked response (ABR) testing, diagnostic evaluation, and intervention. Prior to national scaling-up, the efficiency of this multiple targeted screening (MTS) protocol was evaluated in Havana. Technology and equipment were then developed, and personnel were trained to set up the national screening network. In 1996, the multiple auditory steady-state evoked response (MSSR) technique for objective audiogram estimation was introduced using AUDIX equipment, designed and produced in Cuba for this program. A semi-automated version for neonatal screening has been developed more recently. Several studies have been conducted to evaluate the program's efficiency, coverage, yield, and impact on health. Results During the first stage of implementation in Havana, the MTS protocol correctly identified 72.5% of children with congenital and preverbal hearing loss. Subsequent studies of different aspects of the program have shown that: 1) the mean age of hearing loss detection/intervention in one municipality was reduced from 4 years to 10 months; 2) hearing-impaired children who were screened showed improved language and cognitive development compared to those who were not screened; 3) the MSSR technique predicted type and severity of hearing loss more accurately than physiological techniques used previously and was also shown to be an effective screening method (92% to 96% sensitivity, 100% specificity); and 4) program coverage (25-86%), though reasonably high in some regions, is not complete and needs improvement, particularly in the country's remote and rural areas. Conclusions The MTS protocol can be considered a valid option for increasing the yield and effectiveness of a hearing screening program operating with limited resources. The MSSR technique provides valuable data for the diagnosis and treatment of children detected through a screening program and, with improvements, may also be useful as a screening method.