Table 1 Model parameters
Parameter | Base case (in %) | Range for sensitivity analysis | Source |
|---|---|---|---|
Prevalence of new-born hearing impairment | 0.15 | 0.09–0.3 | [3], [28], [29], [4], [30], [31], [25] |
Prevalence of one or more risk factors for hearing impairment | 20 | - | [2, 25, 32] |
Prevalence of hearing impairment | - | ||
In children with risk factors | 0.38 | - | Author's calculation, [33] |
In children without risk factors | 0.09 | - | Author's calculation |
Prevalence of risk factors in children with hearing impairment | 50 | 48–56 | [1, 28, 34] |
Sensitivity of screening | 96 | 96–100 | [11, 32, 35] |
Specificity of screening | 89 | 77–96 | [11, 32, 35] |
Sensitivity of diagnostic testing | 98 | - | |
Specificity of diagnostic testing | 98 | - | |
Coverage of screening | 90 | 85–95 | Author's estimate |
Follow-up after screening | 80 | 75–85 | Author's estimate |
Healthy children under suspicion of hearing impairment | 0.1 | - | Author's estimate |
Discounting factor | 3 per year | 0–5 | |
Weighs for quality adjustment | |||
Time to diagnosis ≤ 6 months of age | 1 | - | Experts'estimate |
Time to diagnosis > 12 months of age | 0.875 | ||
Time to diagnosis > 6 months and ≤ 12 months | linear extrapolation | ||
Probability of "natural" discovery without systematic screening | Weibull Distribution Median age at diagnosis 18 months | - | Empirical data *) |