Klaske van Sluis

32 2.3. Results Table 2.4: Comparative perceptual and patient-reported outcomes for speaker groups Perceptual Perceptual PROs PROs Voice quality Intelligibility VHI V-RQOL ES>TES - - Salturk et al. [51]* Tiple et al. [53] - ES>ELS Ng et al. [48] Williams&Watson [54]* Salturk et al. [51]* Tiple et al. [53] Moukarbel et al. [47] ES > H - - - - TES>ES Law et al. [43] Ng et al. [48] Williams&Watson [54]* Law et al. [43] Ng et al. [48] Williams&Watson [54]* - Moukarbel et al. [47] TES>ELS Eadie et al. [30]* Ng et al. [48] Miralles&Cervera [46] Williams&Watson [54]* Eadie et al. [30]* Ng et al. [48] Williams&Watson [54]* Eadie et al. [30] Moukarbel et al. [47]* TES>H - - - - ELS>ES Law et al. [43] Law et al. [43] Ng et al. [48] - - ELS>TES Law et al. [43] Law et al. [43] Tiple et al. [53] - ELS>H - - - - H>ES Williams&Watson [54]* Williams&Watson [54]* - - H>TES Finizia et al. [40] Williams&Watson [54]* Finizia et al. [40] Williams&Watson [54]* Crosetti [31]* - - H>ELS Williams&Watson [54]* Williams&Watson [54]* - - > Indicating a better mean group outcome. Level of significance was held at p ≤ .05. Studies presented in bold had a level A risk of bias. ES esophageal speakers, TES tracheoe- sophageal speakers, ELS electrolarynx speakers, MPT maximum phonation time, V-RQOL voice-related quality of life 2.3.2 Perceptual outcomes In Table 4, comparative perceptual results for the different speaker groups are shown. Studies that reported on the primary outcomes “voice quality” and “in- telligibility” are presented. Initially formulated outcome variables, which were not reported in the included studies, cannot be discussed. This concerns the percentage of voicedness, “Grade Roughness Breathiness Asthenia Strain scale assessment” (GRBAS), unattended additive noise, fluency and voicing. Voice quality Voice quality was perceptually evaluated in five studies [30, 40, 43, 48, 54] ( n =177). One of these studies was categorized as level A [30], four level B [40, 43, 48, 54]. Across these studies, different evaluation methods were used. In the level A study by Eadie et al. [30] speech acceptability ratings were obtained for ES, TES and ELS measured by a visual analog scale (VAS). The audio recordings were evaluated by 48 listeners, and speakers judged their own speech acceptability. In another study [43] the evaluators were instructed to rate the severity of the speech impairment on an 11-point scale with equal- appearing interval, from no speech impairment to a severe speech impairment. This study made a distinction between younger and older listeners, and in