Pasa 2007.

Methods	RCT
Participants	37 primary school teachers in Australia Mean age: 37 (SD 9.98) Sex: direct voice training group: 83%, indirect voice training group: 100% and control group: 93% female Teaching experience: 13.59 (SD 9.32) Mean number of teaching per day: 5.54 (SD 0.69)
Interventions	1) Direct voice training (10) The exercises taught to the participants in this study were a modified version of Stemple's VFE. The VFE training the teachers received consisted of 4 exercises (warm‐up, stretching, contracting, and adductory strengthening exercises to be practiced at home, twice each, twice per day, preferably morning and evening, for a 6‐week period. The training session began with a brief discussion about the impact and prevalence of voice problems in teachers, and information about how the normal voice works. The participants in VFE group were then instructed how to perform VFE and how often the exercises need to be performed. The participants were encouraged to produce all the vocal exercises softly, with a frontal focus. The researchers demonstrated to the participants how the exercises were to be performed, instructed the them to produce the exercises themselves as a group, and finally divided the large group into smaller groups (2 or 3 people per group) to practice the exercises. Four student clinicians who were trained to perform VFE by the researchers directed each smaller group. 2) Indirect voice training (13) The vocal hygiene (VH) programme was adapted from the VH programme used by Roy et al. The aim of the VH training was to introduce healthy vocal behaviours into the participants' daily interactions, particularly in the school environment. The topics covered in the VH session were the prevalence and impact of voice problems in teachers, basic anatomy and physiology of voice production, symptoms of voice disorders, strategies to reduce harmful vocal behaviours, managing and minimising health factors that contribute to the development and maintenance of voice problems, and changes to the speaking environment that increase vocal efficiency and reduce vocal harm. 3) No intervention (14)
Outcomes	1) Voice symptoms, vocal misuse behaviours 2) Maximum phonation time, maximum phonational frequency range
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	High risk	"The researchers decided a priori through random allocation that the teachers from the first school that agreed to participate would be allocated to the VH group. If less than 13 teachers decided to participate from this school (the required sample size for each group as determined through power analysis), then the teachers from the second school that volunteered to participate would also be allocated to the VH group. The next group to which a school (or schools) would be allocated was the VFE group, and the final group to which a school (or schools) would be allocated was the control group." (p. 130)
Allocation concealment?	Unclear risk	No details reported regarding whether allocation was concealed or not
Blinding? All outcomes	High risk	This study used self‐reported outcomes and instrumentally assessed outcomes and therefore blinding is not an issue
Incomplete outcome data addressed? All outcomes	High risk	"...at the commencement of the study there were 13 female participants in the VH group, 12 in the VFE group (10 females, 2 males), and 14 in the control group (13 females, 1 male). Two teachers from the VFE group completed the initial assessment but were unable to continue participating in the study... The number of participants in the VFE group was therefore reduced to 10." (p. 130). The authors do not report any details on the 8 individuals who volunteered to participate but could not or the 2 participants who dropped out after baseline measurements. The study suffered a total loss of 21% of the initial sample.
Free of selective reporting?	Low risk	The authors report the results for all the outcomes measured

RCT = randomised controlled trial 
 SD = standard deviation 
 SLP = speech‐language pathologists 
 VFE = vocal function exercises 
 VH = vocal hygiene 
 VHL = vocal hygiene lecture 
 VT = voice training