Self-evaluation as the outcome measure of voice hygienic interventions

This study compared the effects of voice hygiene lecture, voice training and Voice Massage on the vocal well-being of 90 functionally healthy Finnish female primary school teachers (mean age 41.1 years, mean teaching experience 15.3 years). In the beginning of the autumn term, the subjects were randomly divided into three groups, (N 30 in each). One of the groups received only a three-hour voice hygiene lecture (VHL Group). In addition to the lecture, one group received Voice Massage treatment (VM Group) and the other group voice training (VT Group), both treatments were given in five sessions (á 1 hour). In the end of the term the subjects evaluated the influence of the interventions on their voice quality, audibility and vocal endurance or on something else (free description). Both in the beginning and in the end of the term the subjects assessed their voice quality, ease or difficulty of phonation and tiredness of throat before and after a vocally loading working day. A visual-analogous scale was used in the assessment. All three groups reported some positive influence of the intervention, but VHL Group significantly less than VM and VT Groups (p= 0.000). The effect mainly consisted of improved knowledge in VHL Group, increased relaxation and vocal endurance in VM Group and increased knowledge and endurance in VT Group. General assessment of the positive influence of the interventions did not correlate with working-day related changes in sensations. Increased difficulty of phonation and tiredness of throat in VHL Group in the end of the term seems to suggest that VM and VT may have helped the teachers to sustain better their vocal well-being during the term. Introduction Teachers are one of the largest professional groups with voice as the main tool of trade. Voice problems of the teachers are known to be common worldwide, and teachers also form the majority of phoniatric patients (1, 2). Vocal dysfunction may not only have a great negative impact on the teachers’ well-being at work but also on the classroom communication. Hence, it may also disturb the pupils’ learning process. Voice problems are also prone to have remarkable economic consequences in the form of sick-leaves and premature retirement or change of profession. Large amount of voice use, non-ergonomic type of voice use e.g. due to background noise or poor room acoustics, as well as poor quality of air in the classroom and various other ergonomic and psychosocial factors contribute to vocal loading in teaching profession (3, 4). In voice pedagogy and clinical phoniatric praxis, loud, high-pitched and hyperfunctional voice (excessive adduction) has been regarded as one essential cause of voice problems. It seems plausible that the type of voice use largely determines the forces related to voice production and that the forces, in turn, would cause vocal symptoms and later possibly trauma in the vocal fold tissue. An association has been demonstrated between vocal parameters and symptoms of vocal fatigue. More symptoms of vocal fatigue have been reported in those who used higher fundamental frequency (F0) and sound pressure level (SPL) in a loading test (5). Similarly, those teachers who used higher mean F0 and SPL during a working day also experienced more vocal symptoms (6). Voice training and therapy aim at preventing and curing voice problems by changing the vocal habits. Various studies have shown positive acoustic and perceptual effects of voice training and therapy (7-11). Voice hygiene education as such has also been reported to have positive impact (12). Various massage methods have been developed or applied to improve voice production (13, 14). There are some studies showing beneficial effects of these treatments on dysphonic patients’ voices (15, 16). Ternström et al. investigated the immediate effects of 30-minute’s (naphrapatic) massage of the muscles of the back, neck and face for normal-voiced subjects (17). Massage treatment seemed to have a relaxing effect on the muscles involved in voice production, as reflected in lower F0 and SPL. Laukkanen et al. studied the instant effects of one hour Voice Massage (VM) treatment on normal voiced subjects (18). VM is a Finnish method, developed by massage therapist Leena Koskinen (see www.voicemassage.fi). It consists of manipulation of voice and speech production related muscles of the larynx, respiration and articulation. It also includes some stretching and vocal and respiratory exercises during manipulation. VM is used for voice students to improve their training process, for voice professionals to improve performances and to help overcome attacks of vocal fatigue. It has also been used for voice patients (especially those with hyperfunctional dysphonia) as a supportive treatment related to logopedical therapy. According to Laukkanen et al., after one hour VM treatment, no significant acoustic or perceptual effects were found for normal voiced subjects but major positive sensations were reported (18). Various self-evaluation questionnaires have been developed and tested to be used in voice patients to grade the severity of the problems and to serve as the outcome measure of therapy (19, 20). These questionnaires focus on the type and amount of vocal symptoms and their effect on the quality of life. Such questionnaires seem to be less suited to be used in voice professionals with functionally healthy voices. The present study aimed to test possible interventions to support and improve the teachers’ vocal working capacity and well-being at work. Since majority of the teachers are females and since voice problems are twice as common in females than in males, this study focused on female teachers. The interventions chosen were voice hygiene lecture, voice training and Voice Massage. This study also tests two simple, easy to use questionnaires which might be practical in disclosing the effects of vocal loading (e.g. related to daily work) and the outcome of various voice hygienic