Appendix.
Previous studies which investigated speech rate of children who stutter (CWS) and/or children who do not stutter (CWNS)
| Authors | Participants | Age Range | Stuttering Severity | Measurements | Analysis* | Disfluencies | Results |
|---|---|---|---|---|---|---|---|
| Kindergarten: 2.15 SPS | |||||||
| (Mean) | Audio signal | Included unfilled | Grade 2: 2.86 SPS | ||||
| Kowal, O’Connell, & Sabin (1975) | 168 CWNS | 5:10,8:0, | (Bruel and Kjaer | pauses (more | Grade 4: 3.24 SPS | ||
| - Seven age groups | 9:11,11:11, | N/A | audio frequency | SPS | than 270 msec) | Grade 6: 3.26 SPS | |
| 14:1,16:2 | spectrometer & level | and filled pauses | Grade 8: 3.83 SPS | ||||
| 18:1 | recorder) | (i.e., uh, ah, um) | Sophomores: 4.00 SPS | ||||
| Seniors: 3.84 SPS | |||||||
| Disfluent | CWS: 3.51 SPS | ||||||
| Meyers & Freeman (1985) | 12 CWS | 4:0 – 5:11 | 5 moderate | Video time-code | SPS | utterances | Severe: 3.29 SPS |
| 12 CWNS | 7 severe | excluded | Moderate:3 84 SPS | ||||
| CWNS: 4.04 SPS | |||||||
| Audio signal | |||||||
| Stephenson-Opsal & Bernstein Ratner (1988) | 2 CWS (p1 & p2) | 3:3 (p1) | Severe (p1) | (Bruel and Kjaer | SPS | Excluded | Specific articulation rates |
| 6:2 (p2) | Moderate (p2) | graphic level | were not reported | ||||
| recorder) | |||||||
| 3 yrs: | |||||||
| 140.3 SPM (OS) | |||||||
| Pindzola, Jenkins & Lokken (1989) | 30 CWNS | 3:0 – 3:9 | 170.8 SPM (AR) | ||||
| - Three age groups | 4:0 – 4:9 | N/A | Stop watch | OS & AR | Included in OS | 4 yrs: | |
| 5:0 – 5:9 | SPM | Excluded in AR | 152.7 SPM (OS) | ||||
| 186.2 SPM (AR) | |||||||
| 5 yrs: | |||||||
| 152.2 SPM (OS) | |||||||
| 180.8 SPM (AR) | |||||||
| CWS: | |||||||
| 164.18 WPM (OS) | |||||||
| 189.72 SPM (OS) | |||||||
| 174.41 WPM (AR) | |||||||
| 5 mild | Acoustic analysis | OS & AR | Excluded | 200.21 SPM (AR) | |||
| Kelly & Conture (1992) | 13 CWS | 3:3 – 4:8 | 7 moderate | (Micro Speech Lab) | WPM, SPM | CWNS: | |
| 13 CWNS | 1 severe | 153.63 WPM (OS) | |||||
| 177.54 SPM (OS) | |||||||
| 157.33 WPM (AR) | |||||||
| 180.74 SPM (AR) | |||||||
| Ryan (1992) | 20 CWS | 2:10 – 5:9 | No explanation | Stop watch | SPM | No explanation | CWS: |
| 20 CWNS | WPM | 174.6 SPM, 131.1 WPM | |||||
| CWNS: | |||||||
| 167.2 SPM, 131.7 WPM | |||||||
| 3yrs: | |||||||
| Spontaneous: | |||||||
| 3.82 SPS, 8.42 PPS | |||||||
| Imitated: | |||||||
| 3.58 SPS, 7.09 PPS | |||||||
| Overall: | |||||||
| Walker, Archibald, Cherniak, & Fish (1992) | 40 CWNS | 2:11 – 3:2 | N/A | Acoustic analysis | AR | 3.70 SPS, 7.92 PPS | |
| - Two age groups | 4:11 – 5:2 | (MacSpeech) | SPS, PPS | No explanation | 5yrs: | ||
| Spontaneous: | |||||||
| 4.28 SPS, 9.47 PPS | |||||||
| Imitated: | |||||||
| 3.94 SPS, 8.54 PPS | |||||||
| Overall: | |||||||
| 4.11 SPS, 9.00 PPS | |||||||
| CWS: | |||||||
| 191.2 SPM (OS) | |||||||
| 197.2 SPM (AR) | |||||||
| Kelly (1994) | 11CWS | 4 mild | Acoustic analysis | OS & AR | Excluded | CWNS: | |
| 11CWNS | 2:7 – 10:1 | 5 moderate | (Micro Speech Lab) | SPM | 194.7 SPM (OS) | ||
| 2 severe | 195.3 SPM (AR) | ||||||
| Fluent utterances: | |||||||
| Logan & Conture (1995) | 15 CWS | 3:0 – 5:6 | 5 mild | Video time-code | AR | Excluded | 230.46 SPM |
| 10 moderate | SPM | Stuttered utterances: | |||||
| 222.32 SPM | |||||||
| Yaruss & Conture (1995) | 10 CWS | 4:0 – 5:10 | 4 mild | Frame-by-frame | AR | Disfluent | CWS: 3.40 SPS (overall) |
| 10 CWNS | 6 moderate | (33ms per frame) | SPS | utterances | Mild: 4.03 SPS | ||
| excluded | Moderate: 2.93 SPS | ||||||
| CWNS: 3.56 SPS | |||||||
| 18 CWS | |||||||
| - Normal (NP) / | 4 very mild | ||||||
| Yaruss & Conture (1996) | disordered (DP) | 3:9 – 6:10 | 10 mild | Frame-by-frame | AR | Excluded | CWS+NP: 3.82 SPS |
| phonological | 4 moderate | (33.33ms per frame) | SPS | CWS+DP: 3.65 SPS | |||
| development | |||||||
| 3 very mild | |||||||
| Yaruss (1997) | 12 CWS | 3:4 – 5:6 | 6 mild | Frame-by-frame | AR | Excluded | 3.69 SPS |
| 3 moderate | (33.33ms per frame) | SPS | |||||
| Howell, Au-Yeung, & Pilgrim (1999) | 8 CWS | 9 – 11 yrs | 4.91 – 35.83 | Acoustic analysis | SPS | Excluded | Specific articulation rates |
| (Stuttering rate) | were not reported | ||||||
| CWS (persistent) | |||||||
| Initial: 3.84 SPS, 9.56 PPS | |||||||
| 1yr: 3.94 SPS, 9.66 PPS | |||||||
| 2yr: 4.12 SPS, 10.22 PPS | |||||||
| 16 CWS | Disfluent | CWS (recovered) | |||||
| Hall, Amir, & Yairi (1999) | - 8 persistent | 3:1 – 4:10 | No explanation | Acoustic analysis | AR | utterances | Initial: 3.18 SPS, 7.68 PPS |
| - 8 recovered | (Cspeech) | SPS, PPS | excluded | 1yr: 3.87 SPS, 9.78 PPS | |||
| 8 CWNS | 2yr: 3.75 SPS, 9.38 PPS | ||||||
| CWNS | |||||||
| Initial: 3.84SPS, 11.42PPS | |||||||
| 1yr: 3.94 SPS, 12.17 PPS | |||||||
| 2yr: 3.92 SPS, 11.88 PPS | |||||||
| OS | |||||||
| CWS | |||||||
| (WPM, | OS: excluded | 170.0 WPM (OS) | |||||
| Ryan (2000) | 30 CWS | 2:10 – 5:9 | AR: Disfluent | 202.6 SPM (OS) | |||
| 30 CWNS | No explanation | Stop watch | utterances | 4.1 SPS (AR) | |||
| SPM) | excluded | CWNS | |||||
| 169.1 WPM (OS) | |||||||
| 205.6 SPM (OS) | |||||||
| AR | 3.8 SPS (AR) | ||||||
| (SPS) | |||||||
| CWS | |||||||
| Spontaneous: | |||||||
| 4.84 SPS (OS) | |||||||
| 5.26 SPS (AR) | |||||||
| OS (SPS) | Story telling: | ||||||
| OS: excluded | 3.36 SPS (OS) | ||||||
| 10 CWS | 3 mild | Acoustic analysis | AR: Disfluent | 4.32 SPS (AR) | |||
| Chon, Ko, & Shin (2004) | 10 CWNS | 4:0 – 5:10 | 5 moderate | (PCQuirer 4.9.6) | AR (SPS) | utterances | CWNS |
| (Korean speaking | 2 severe | excluded | Spontaneous: | ||||
| children) | 4.94 SPS (OS) | ||||||
| 5.07 SPS (AR) | |||||||
| Story telling: | |||||||
| 3.66 SPS (OS) | |||||||
| 3.99 SPS (AR) | |||||||
| Walker & Archibald (2006) | 16 CWNS | 4:0 – 4:2 | N/A | Acoustic analysis | AR | No explanation | 4 yrs (first visit): |
| - Three visits | 5:0 – 5:2 | (MacSpeech) | SPS, PPS | Spontaneous: 3.56 SPS | |||
| 6:0 – 6:2 | (The authors | Imitated: 3.37 SPS | |||||
| did not | Automatic: 3.93 SPS | ||||||
| provide the | Repetition: 4.14 SPS | ||||||
| results of | Overall: 3.75 SPS | ||||||
| PPS.) | 5 yrs (second visit): | ||||||
| Spontaneous: 3.19 SPS | |||||||
| Imitated: 3.11 SPS | |||||||
| Automatic: 3.52 SPS | |||||||
| Repetition: 3.74 SPS | |||||||
| Overall: 3.39 SPS | |||||||
| 6 yrs (third visit): | |||||||
| Spontaneous: 3.38 SPS | |||||||
| Imitated: 3.30 SPS | |||||||
| Automatic: 4.30 SPS | |||||||
| Repetition: 4.08 SPS | |||||||
| Overall: 3.76 SPS |
*
Overall speaking rate (OS), Articulation rate (AR), Phones per second (PPS), Syllables per second (SPS), Syllables per minute (SPM), Words per minute (WPM)