Does stuttering impact labour market outcomes in the USA? Results from a national longitudinal study
“Stuttering was associated with reduced earnings and other gender-specific disadvantages in the labor market.” – Gerlach et al., 2018
This study utilised survey data collected as part of the Add Health study, an ongoing longitudinal study following individuals living in the United States from adolescence through to adulthood.
Labour market outcomes include things like annual earnings, levels of unemployment, and underemployment (this refers to people who are working at a lower level than they are qualified for, or are working fewer hours than they would like). Such outcome measures were compared between 261 individuals who stuttered (92 females and 169 males) and 13,303 individuals who didn’t stutter (6,988 females and 6,315 males) in adulthood. Outcomes for this study were extracted from the 4th wave of the study, where participants were an average of 30 years old.
What did the study show?
Results showed that stuttering was associated with disadvantages in labour market outcomes. That is, males and females who stuttered earned less annually compared with those who did not stutter. Males who stuttered were less likely to be working than males who didn't stutter. Females who stutter are more likely to be underemployed than females who do not stutter.
What is behind the earnings gap for those who stutter vs those who don't stutter?
In males and females, there were different reasons for the earnings gap, as highlighted below:
For males who stuttered:
- 33% of the earnings gap was accounted for by differences in occupation, i.e., working in lower paying occupations;
- 16% by background characteristics, e.g., lower parental income;
- 17% by self-stigma, ie higher levels of self-stigma (more likely to describe themselves as quiet, nervous, insecure etc.);
- 12% by education, i.e., lower levels of education; and
- 17% by weekly hours worked, i.e., worked fewer hours.
For the females who stuttered:
- Approximately 20% of the earning gap was accounted for by differences in education, i.e., lower levels of education;
- 12% by occupation, i.e., lower-paying jobs;
- 6% by comorbidities, i.e., higher likelihood of attention or learning difficulties; and
- 3% by self-stigma, i.e., higher levels of self-stigma.
It is important to note, that this study's results are based on observational data and therefore we cannot rule out that other factors, not measured in the study, are also driving the association between stuttering and earnings.
How do these results compare to the similar UK based study (McAllister, Collier & Shepstone, 2012)?
Results from this study contrast earlier UK based results, which only showed an association between stuttering and job socioeconomic status, but not earnings. There are a number of possible explanations, which should be considered when interpreting results from these two studies:
- Different measures and statistical analysis techniques were used in each study. This impacts the data that was available for analysis and the way in which results were interpreted.
- Males and females were differentiated in Gerlach et al’s analyses, and grouped in McAllister’s analyses. The differentiation in the present study allowed researchers to examine factors that may have been independently associated with either males or females.
- The populations examined may have been different on a number of levels:
- Timing and social stigmatisation of stuttering – these studies were completed at different time points, and when participants were different ages. The social perception and associated stigmatisation of stuttering may have been different across these time points.
- Populations – the overall demographic, socioeconomic status and labour market disadvantages may have differed between the two cohorts.
Both of these studies provide a valuable contribution to the literature and increase our understanding of the impact of stuttering.
Gerlach, H., Totty, E., Subramanian, A. & Zebrowski, P. (2018). Stuttering and the labor market outcomes in the United States. Journal of Speech, Language and Hearing Research, 61, 1649-1663. doi: 10.1044/2018_JSLHR-S-17-0353
Referenced study:
McAllister, J., Collier, J. & Shepstone, L. (2012). The impact of adolescent stuttering on educational and employment outcomes: evidence from a birth cohort study. Journal of Fluency Disorders, 37(2), 106-121. doi: 10.1016/j.jfludis.2012.01.002
