Dr. Ingo Titze and his colleagues at the National Center for Voice and Speech explored three areas relating jobs and voice use.

1. what jobs are most often represented among the clients at voice centers?
2. how many working Americans may be classified as professional voice users? and
3. what percentage of the U.S. workforce needs healthy voices to ensure public safety?

Voice Professionals seen in Clinics
At least four studies have identified professions most often represented among people who seek help at voice centers. The investigators tallied clients' jobs at voice centers in Iowa, Ohio, Utah, Wisconsin and Sweden.

In three of the four studies, teachers were identified as the professional group most frequently treated for voice problems. Other occupations often represented include: retired persons (previous profession unknown), entertainers (singers and actors), factory workers or machine operators, managers, clerical workers, and sales personnel.

Voice Professionals as a Percentage of the Workforce
In another investigation, Dr. Titze and his colleagues categorized U.S. workers by occupation using figures from the U.S. Bureau of Labor Statistics and professional organizations. To maintain consistency, all numbers were based upon 1994 statistics using a total of 123,060,000 U.S. workers. Once the entire labor pool was divided into career categories, professions requiring voice use were identified. Discussions of several occupational groups are presented below.

It is interesting to compare the percentage of Americans within a career category with its representation at voice centers. If the representation at voice centers is higher, it may mean that the job is vocally demanding. Thus, workers within this job group may be at higher "vocal risk" as compared to other professionals.

Salespeople compose about 13 percent of the U.S. workforce; in general, their appearance in voice centers is about equal to their workforce percentage. However, those in telephone sales constitute 0.78 percent of the U.S. workforce, but make up 2.3 percent of the clinic load. Thus, within the professional group of salespeople, telemarketers may be at the most severe vocal risk.

Teachers represent 4.2 percent of the U.S. workforce. However, this group constitutes almost 20 percent of the voice-clinic load, a five-fold disproportion Dr. Titze calls "quite remarkable."

Receptionists and public relations workers make up slightly less than 1 percent of the U.S. workforce. It is unknown what fraction of clinic load they represent; Dr. Titze estimates it is 3-4 percent.

Lawyers and judges who regularly speak in court are only about 0.1 percent of the U.S. workforce. Unfortunately, information about their appearance at voice centers is currently unknown.

Clergy, psychologists, counselors and speech-language pathologists compose 0.8 percent of the total U.S. workforce. While all subgroups in this category couldn't be compared to the voice clinic data, it is known that counselors constitute only about 0.2 percent of the workforce, but are 1.6 percent of the voice center clientele.

Telephone operators make up 0.13 percent of the workforce and are 0.4 percent of the clinical voice load.

Interviewers/recruiters are about 0.13 percent of working Americans; specific clinic-load data is not available.

Actors, directors, broadcasters and singers are a difficult group to enumerate. Many individuals in this group pursue entertainment on a part-time or hobby basis. However, an interesting subgroup was singers, which was estimated as 0.02 percent of the workforce, while the sampled clinic load was 11.5 percent.

The table below summarizes several comparisons.

Occupation, ages 16 and older	Percent of working US population	Percent of clinic load
Factory workers	14.53	5.6
Salespeople	12.97	10.3
Clerical workers	10.57	8.6
Teachers	4.2	19.6
Counselors	0.19	1.6
Singers	0.02	11.5

Voice and Public Safety
Finally, professionals whose vocal well-being impacts on public safety were tallied. This group includes: the military, police officers, construction supervisors, dispatchers, firefighters, pilots and air traffic controllers. These professionals as a group make up about 3 percent of the U.S. workforce. While this group is somewhat small, the ability of these professionals to use their voices reliably has the potential of literally saving lives.

This study is just the beginning of many possible investigations relating vocal capability to the vocal demands of various professions. How loudly and how frequently professionals use their voices are other important factors for prevention of disorders. This information, a logical next area of investigation, can help speech-language pathologists and voice educators better understand the professional demands of their clientele.

A full treatment of this investigation is published in Titze, I., Lemke, J., Montequin, D. Populations in the U.S. Workforce Who Rely on Voice as a Primary Tool of Trade: A Preliminary Report. The Journal of Voice 11(3), 254-259.