Gender, the individual, and intelligibility

In the clinic and in the laboratory, opinions differ on the relative intelligibility of the speech of women and men. However, the effect of gender alone has rarely been studied explicitly. Here we present a study of 30 talkers (15 male) and 32 listeners assessing intelligibility of a 180-sentence subset of the IEEE sentences presented in steady-state speech-shaped noise. Four signal-to-noise ratios (−4, −2, 0, + 2 dB SNR) were tested with 45 sentences each. Results showed substantial overlap between intelligibility scores for each gender. Although standard statistical approaches show a slight advantage for female talkers at all SNRs, post-hoc analyses indicated that the gender effect is an artifact driven by a few particularly unintelligible males. These results do not address intrinsic gender-related differences in speech intensity, or in the ability to overcome background noise by speaking clearly, but suggest that gender-related differences are negligible when those factors are controlled. More generally, even with a large sample of talkers, the high degree of talker-intrinsic variability in intelligibility can lead to conclusions that do not generalize to the population of interest, an issue that could affect comparisons rooted in gender, dialect, or other social factors.