No Effect of Interstimulus Interval on Acoustic Reflex Thresholds.
Hannah Guest, Kevin J Munro, Samuel Couth and 5 others
PMID 31516095WHAT IT FOUND
Lengthening the pause between sounds during acoustic reflex testing did not lower thresholds or improve reliability in young adults with normal hearing.
A short 2.5-second interval is sufficient for accurate testing at both 1 kHz and 4 kHz frequencies.
Key findings
01Increasing the interstimulus interval from 2.5 to 8.5 seconds did not significantly reduce acoustic reflex thresholds at 1 kHz or 4 kHz.
02Test-retest reliability remained high (excellent or good) regardless of whether a short or long interstimulus interval was used.
03The study suggests that a 2.5-second interstimulus interval is adequate for clinical acoustic reflex threshold measurement in young adults with normal hearing.
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The sample size in Study 1 (n=24) was smaller than originally planned (n=40) due to a power analysis error, though post-hoc calculations confirmed sufficient power. The participants were all young adults (18-30) with normal hearing, so the findings may not apply to older adults or those with hearing loss. Study 2 used immediate retesting (probe removal and replacement) rather than separate sessions, which may affect how generalizable the reliability estimates are to typical clinical workflows involving different days.
Declared interests
The research was funded by the Medical Research Council and the NIHR Manchester Biomedical Research Centre. The authors declared no conflicts of interest.
The easy way to misread this
Do not assume these findings apply to patients with hearing loss or older adults. The study only tested young people with normal hearing, and the authors note that reflex prevalence and characteristics can vary significantly with age and pathology.