A critical review of the role of neonatal hearing screening in the detection of congenital hearing impairment.

Abstract

Glossary and list of abbreviationsTechnical terms and abbreviations are used throughout this report.The meaning is usually clear from the context but a glossary is provided for the non-specialist reader.In some cases usage differs in the literature but the term has a constant meaning throughout this review.Permanent hearing impairment Average hearing levels measured at ≥ 40 dB HL on all occasions. Congenital hearing impairmentHearing impairment considered by examination of the case history to be present and detectable using appropriate tests at or very soon after birth.This was the default classification when there was no indication in the case notes of the presence of an acquired impairment or evidence of a progressive or a late-onset element to the impairment. Acquired hearing impairmentHearing impairment acquired post-natally or of lateonset or progressive nature which, on the basis of case history was not considered to be present and detectable using appropriate tests at or very soon after birth. SpecificityThe ability of a programme to screen out individuals who are not cases (e.g. in a screening programme, the percentage of unaffected individuals who pass the screen).contd Executive summary Scope A summary of the major effects of permanent childhood hearing impairment (PCHI) are presented in this chapter, together with an outline of the historical arguments for early identification and screening.A brief history of childhood hearing screening in the UK is followed by an outline of current concerns about identification and service provision in the light of new developments and, hence, the need for this critical review.The main review questions, an outline of the review procedures, and the structure of the report are summarised. ScopeA public health perspective on PCHI is presented in this chapter.Epidemiological data relating to the UK are presented and reviewed: the prevalence of PCHI as a function of severity, onset and demographics; the natural history of PCHI, that is, its onset and development; the major risk factors for PCHI; the differential aetiology of PCHI, and the current service indicators or proxy outcome measures, for example, the age of referral, confirmation and fitting of hearing-aids for PCHI.Severity of hearing impairment (dB HL) England Wales Scotland N Ireland ≥ 40 837 (767-912) 47 (43-51) 82 (75-89) 32 (30-35) ≥ 50 692 (629-761) 39 (35-43) 68 (62-75) 27 (24-29) ≥ 60 509 (453-566) 29 (25-32) 50 (44-56) 20 (17-22) ≥ 70 371 (327-421) 21 (18-24) 36 (32-41) 14 (13-16) ≥ 80 296 (258-346) 17 (15-19) 29 (25-34) 11 (10-13) ≥ 90 220 (182-264) 12 (10-15) 22 (18-26) 9 (7-10) ≥ 95 195 (151-245) 11 (8-14) 19 (15-24) 8 (6-9) ≥ 100 151 (120-182) 8 (7-10) 15 (12-18) 6 (5-7) ≥ 110 69 (50-94) 4 (3-5) 7 (5-9) 3 (2-4) ≥ 120 25 (19-44) 1 (1-2) 2 (2-4) 0 (0-2)TABLE 6 The estimated number of children (with 95% CIs) with congenital PCHI in the four countries of the UK per annual birth cohort estimated from the birth cohort of 1994, using the prevalence data from Table 2 Severity of hearing impairment (dB HL) England Wales Scotland N Ireland ≥ 40 704 (635-774) 40 (36-44) 69 (62-76) 27 (25-30) ≥ 50 566 (509-629) 32 (29-35) 56 (50-62) 22 (20-24) ≥ 60 403 (352-453) 23 (20-25) 39 (35-44) 16 (14-17) ≥ 70 296 (258-346) 17 (15-19) 29 (25-34) 11 (10-13) ≥ 80 233 (195-277) 13 (11-16) 23 (19-27) 9 (8-11) ≥ 90 176 (145-208) 10 (8-12) 17 (14-20) 7 (6-8) ≥ 95 151 (120-182) 8 (7-10) 15 (12-18) 6 (5-7) ≥ 100 113 (88-138) 6 (5-8) 11 (9-14) 4 (3-5) ≥ 110 57 (38-75) 3 (2-4) 6 (4-7) 2 (1-3) ≥ 120 19 (13-38) 1 (0-2) 2 (1-4) 0 (0-1)• Neonatal screening • HVDT • SES.An indication of the organisation, purchasing, implementation and effectiveness of these screens is obtained that informs the context in which choices between future options may be made.