Abstract:
PURPOSE : This study aimed to describe and compare the
performance of two screening protocols used for preschool
hearing screening in resource-constrained settings.
METHOD : Secondary data analysis was done to determine
the performance of two protocols implemented during a
preschool hearing screening program using mobile health
technology in South Africa. Pure-tone audiometry screening
at 25 dB HL for 1000, 2000, and 4000 Hz in each ear was
used by both protocols. The fail criterion for the first protocol
(2,147 children screened) constituted a no-response on one or
more frequencies in either ear. The second protocol required
two or more no-responses (5,782 children). Multivariate
logistic regression models were used to investigate associations
between outcomes and protocol, age, gender, and duration.
RESULTS : Fail rates for the one-frequency fail protocol was
8.7% (n = 186) and 4.3% (n = 250) for the two-frequency
fail protocol. Children screened with the two-frequency fail protocol were 52.9% less likely to fail (p < .001; OR = 0.471;
95% confidence interval [0.385, 0.575]). Gender (p = .251)
and age (p = .570) had no significant effect on screening
outcome. A percentage of cases screened (44.7%) exceeded
permissible noise levels in at least one ear at 1000 Hz across
both protocols. True- and false-positive cases did not differ
significantly between protocols. Protocol type (p = .204),
gender (p = .314), and age (p = .982) did not affect the
odds of being a true-positive result. Average screening time
was 72.8 s (78.66 SD) and 64.9 s (55.78 SD) for the onefrequency
and two-frequency fail protocols, respectively.
CONCLUSIONS : A two-frequency fail criterion and immediate
rescreen of failed frequencies significantly reduced referral
rate for follow-up services that are often overburdened in
resourced-constrained settings. Future protocol adaptations
can also consider increasing the screening levels at 1000 Hz
to minimize the influence of environmental noise.
