Repeat Measure

Once five individuals agreed and were available for the study intelligibility testing was undertaken to establish a baseline performance. Twice a week a speech sample of fifty randomly selected words from the Yorkston Beukelman Assessment of the Intelligibility of Dysarthric Speech (1981) was audio-taped by each subject. If the subject was able, once a week they also read 20 sentences, comprising 2 sentences of 5 to 15 words each. These tapes were later transcribed to establish what percentage of the words were understood. Intelligibility was tested twice a week with either one or two days between the sessions. The test session was held within one hour of the appointed time each day for each subject, and in a setting where the researcher and the subject were alone, in a room with a closed door without interruptions or undue background noise. The setting was held constant for each individual although it was

not constant across individuals. This is appropriate to a study where it is the

individual’s performance across time that is the concern and not the rank ordering of subjects (see Section 3.4.3).

The YB Intelligibility Test was used according to the standardised rules of administration accompanying the test with a few exceptions. Deviations from the protocol consisted of increasing the letter size of the sentence stimulus material (see

pp.63), using the tester as listener (see pp. 117) and giving non-specific, non­ performance related verbal reinforcement to subjects (see pp. 144). The reasons for each of these deviations will be discussed subsequently. A procedural reliability checklist was created using the standardised YB Intelligibility Test instructions and taking into account the specific needs of this study. This checklist was displayed prominently with the equipment as a reference for the researcher (see Appendix F). A key for each taping session was made using the random number table to select 1 of 12 similar sounding words for each of 50 items (see Appendix G). The date and the subject’s name was written on the key. After the session it was filed for checking once judging was complete. Each intelligibility test for each subject was from the same pool of words but a different and equivalent test was created each time (see Section 3.2.2).

There was a conscious attempt to minimise social interaction with the subject before the testing and where possible the equipment was set up before the subject was taken to the room. The door was closed and a notice asking for quiet and no interruptions due to voice taping was placed on the outside of the door. At this time one subject, RP, was encouraged to assume a comfortable, upright and optimal posture. Four of the five subjects were disabled enough that they moved very little and their habitual posture and comfort was ensured (see Section 3.4.4). If there was a problem then a nurse was summoned to assist in positioning the subject. Intelligibility tests were taped using a boom microphone stand with an R 249-946 Dynamic Microphone connected to a Marantz Model C230 tape recorder using TDK lECI Type 1 cassette tapes. All recording was done using battery power rather than mains power

to avoid mains frequency interference. The equipment’s batteries were recharged

place the microphone 8 inches from the mouth of the subject. A wooden ruler confirmed the distance. The researcher sat opposite the subject with the microphone between them. Thus the subject focused ahead on the researcher and straight into the microphone. The tape recorder was turned on and the researcher verbally recorded the subject’s name and the test date. The subject was asked to speak and the volume control on the Marantz tape recorder adjusted so that the needle on the VU meter was positioned in the midrange of the dial. The tape recorder was put on pause and the following instructions given:

“I want you to read a series of words. I’ll say the number then you say the word I point to. Say each word as clearly as you can but don’t say anything else. OK?”.

After the subject indicated consent the pause button was released and the researcher said the number and pointed to the target word indicated by the key. The subject read the word. The page was turned, the next item number announced by the researcher, the word was pointed to and read by the subject. This was repeated for all fifty words. Despite the fact that the researcher’s voice was recorded on the tape the microphone was never turned in her direction. If the subject had reading difficulties then the tape was put onto pause after the number of the item had been recorded and the researcher said the target word. The pause button was released so that the tape recorder was recording and the subject repeated the word. The next number was then recorded and the tape paused. This procedure was repeated for all fifty words. Each subject used either reading or imitation for all sessions. There was no mixing of presentation formats.

Non-specific verbal reinforcement was given, directed towards finishing the task and not the production of the specific item: thus, “Well done”, “We’re half way”.

“We’re almost there”. Figure 4 indicates the specific settings and procedures used for each subject:

Subject Task Presentation T arget Time Judging Task Posture

VG YB Words Reading 11:00 Multiple Choice Chair 100%

RP YB Words

YB Sentences Reading 10:30 Transcription

Chair 100%

GF YB Words

YB Sentences Reading 10:00 Multiple Choice

Chair 100% Immobile

EB YB Words Imitation 11:30 Multiple Choice Bed 60% Chair 40%

Immobile

WR YB Words

YB Sentences Reading 13:30 Transcription

Chair 100% Immobile

Figure 4: Intelligibility Testing: Subjects, Settings and Procedures

A short break was taken after the words were finished and the microphone to mouth distance rechecked. The following instructions were given:

“Now the second part involves reading sentences. Follow

along as I read these sentences. Then I’ll turn the recorder on, say the number and you read the sentence OK?”.

The sentences were those provided by the YB Intelligibility Test but they had been increased in size so that the letters were 0.5cm tall, similar to the word items. The format of the YB Intelligibility Test was maintained but each sheet was now A3 size. This was done to assist clarity and ease of reading and thus to avoid errors by misreading. After the subject indicated readiness, the sentence was isolated with a template and the researcher read the sentence aloud drawing her finger along the line. The tape recorder was turned on and the number of the item read. The subject read the sentence. The tape recorder was put onto “pause” and verbal reinforcement given: “Well done” or “Good” no matter what the performance. The next sentence was isolated with the template and read by the researcher and the session continued until all twenty sentences had been recorded. Where a subject’s dysarthria was such that they could not complete the sentence taping, only words were used. As this was an onerous and tedious task for these subjects, sentence taping was done only once a week compared to twice for the words.

On completion o f the test the researcher relaxed with the subject and there was general discussion.

A diary sheet was filled out indicating the date, location and time the session started and finished. Whether it was a control visit, or sentence or word intelligibility had been tested was indicated in the diary, as was the subject’s affect, deviations from

protocol and other comments (see Appendix H). ^ y

2.3.2 Therapy

The first subject, VG, had five baseline intelligibility tests recorded before therapy was initiated, the least number o f baseline recordings for any subject. Therapy was d a i||, lasted a maximum o f fifteen minutes and followed taping on the two days a week when intelligibility continued to be tested. There was no concern to control for the setting in which therapy was performed although in most cases it was in the same room as the tape recorded sessions as this was the most convenient private place. From the time the first subject, VG, began his therapy all subjects were visited every day, even on the days when there was no voice recording done so that there was a control for daily involvement with the researcher. Non-recording, non-therapy visits involved a general discussion o f the subject’s or researcher’s activities, families, opinions, etc., were five to ten minutes in duration and were recorded in the subject’s diar}'.

A therapy session involved stopping the tape after the YB Intelligibility Test was complete and removing the microphone. Posture was again adjusted and deep breathing with long exhalation demonstrated. The researcher put her hand on her stomach to show the stomach moving out during inhalation and in on exhalation (see Section 3.3).

A Sherwood Medical Voldyne 5000 (see Figure 21) inhalatory spirometer mouthpiece was placed in the subject’s mouth and the first attempt at a maximum inhalation made (see Section 3.3). The volume in millilitres (mis.) was noted and then repetition to that value encouraged. As confidence increased the subject was encouraged to hold at the point of maximum inhalation for as long as 3 seconds. The goals were to increase the number of mis. that the subjects could inhale, the number of repetitions that they could repeat that inhalation for and their ability to hold the maximum inhalation. The actual goal values were specific to each individual.

Exhalatory volume and pressure was addressed using the respiratory drive indicator developed by the Speech Pathology Department at Manchester Polytechnic (see Section 3.3). The appropriate mouthpiece was fitted to the respiratory drive indicator and the subject encouraged to exhale. Each exhalation was timed and the subject told the time and encouraged to lengthen the next exhalation. Two methods of visual feedback for pressure during exhalation were available: a wand that indicated inadequate breath pressure by a yellow light, adequate breath support for speech by a green light and excessive pressure by a red light, and a calibration meter that showed the actual pressure reading numerically (see Section 3.3). Both feedback methods were used according to subject preference. Subjects were encouraged to maintain adequate breath support for the longest time they could, avoiding both excessive bursts of pressure and insufficient blowing. The goals were to extend the length of time that the subject could exhale with adequate pressure. As the subject became proficient with achieving a pressure target they were encouraged to attempt the target without looking at the feedback devices. Figure 5 summarises the therapy goals:

Task Goal

Inhalation 1. Increase number of mis. inhaled

2. Increase number o f maximum repetitions

3. Hold up to 3 seconds at point of maximum inhalation

E xhalation 1. Attain target breath pressure

2. Extend length of time exhaling at target pressure

Figure 5: Therapy Goals for Subjects

Five minutes for posture, breathing demonstration and inspiratory exercises and a further five minutes for expiratory exercises was considered the maximum without causing undue fatigue. A diary sheet was completed with the date, time and location of the sessions and the subject’s affect. Posture, breathing patterns, the number of repetitions and target pressures or times were noted. The total time on respiration exercises was recorded and whether or not the therapy session followed intelligibility testing. Any deviations from protocol were noted as well as any other comments. There was no way of telling if the subject had improved other than by subjective observation, since the judging and transcription of the intelligibility tests was done after all the taping was completed. After consultation with the literature a fairly arbitrary length of time of 4 to 6 weeks of daily therapy was decided upon (see Section 3.3). Improvement, if it were to occur, would likely occur within this time. It was anticipated that there would be a delay before any effect of therapy was felt. Improved breath support would be more likely to occur after some time and experience with new breathing styles.

2.3.3 Judging

The result, after four months of taping, was 120 YB Intelligibility Tests for single words that needed to be transcribed. Transcription of the intelligibility tests was not done until after all the taping was completed. The researcher listened to the tapes in a random order, both for subjects and for recording dates. Listening was first done four months after the completion of the tapes so there was no question of

remembering the words used on individual sessions with a particular subject. This and the random order in which the tapes were listened to meant that it was not possible that the researcher could know whether the subject was in or out of therapy and consciously or unconsciously modify her listening pattern. Similarly there was no difficulty with a learning effect as an excellent knowledge of the speaking patterns of the subject and the word pool used in the tests, was applied to all taped sessions in an equal manner. Thus there was no possibility that tapes listened to later benefited from increased knowledge of the researcher/listener as this knowledge was maximised before the judging began (see Section 3.2.2).

A procedural reliability checklist forjudging sessions was made and kept with the subject tapes for constant reference. This checklist details the exact procedure used for listening to the tapes (see Appendix F). A tape was chosen at random from a box with all the subject tapes in it. The tape was placed in the tape recorder and the closest, untranscribed session found. Information about the subject, tape designation, date of the taping session was recorded on a Daily Listening Record (see Appendix H) and the session about to be listened to was marked as transcribed on the tape cover.

The judge listened to each word and either transcribed it or circled the word from a choice of twelve similar sounding words, depending on the format chosen as appropriate for that subject. The choice of format was dictated by the severity of the subject’s dysarthria as suggested by the research in support of the publication of the YB Intelligibility Test (see Section 3.2.2). There was no mixing of judging formats. All the tapes for one subject were listened to using the same judging format.

When listening, one repetition of an item was allowed, as required by the judge. The speaker, date of taping, the judge and the date of listening were all recorded on the YB Intelligibility Test answer sheet. No more than five sessions were

listened to without a break and a maximum of twenty sessions were listened to in a day for a maximum of 5 hours a day. At the end of each listening session the answer sheets were stapled together with the Daily Listening Record as a cover sheet and filed until all the YB Intelligibility Tests had been listened to.

It took 6 weeks for the listening to be completed. At the conclusion the keys made at the time of recording the intelligibility tests were compared to the answer sheets generated during the listening sessions. A percentage was calculated of the number of words correctly heard by the listener for each session. When all the sessions had been graded graphs were made of each subject’s performance across time. It was then checked when therapy had started for each subject and this was marked on the graph.

Listening was done using the same Marantz C230 tape recorder used for the

original taping. Tapes were listened to through Sennheiser HD 480 Classic-II

earphones. Volume was adjusted according to the listener’s preference at the

beginning of the session. Volume was not readjusted during the listening.

In addition 23% of the sessions, all the sessions for one subject, were re­ listened to randomly in the same format as above 16 months and 25 months after the first listening session, and thus 20 and 29 months after the taping, and a comparison of the three performances by the same judge was made. This was to provide test-retest reliability data.

To provide reliability data on the reproducibility of the results a second judge listened to sessions of subject GF. The judge was trained by having an hour of practice listening to sessions of one subject, GF, with the researcher who suggested alternative words, or difficulties the subject was having (see Section 3.2.2). The word pool from which the subject was speaking was available to the listener and the various

alternatives discussed with him. Thus the second listener was familiarised both with the potential word pool, the particular voice and the task that was expected of him. After a half-hour break, a selection of the baseline and therapy sessions, including best and worst performances of this subject was played for the judge, using the headphones with the judge controlling the volume and knowing he was allowed one play back at will. The second judge could not know whether a session was baseline or not. Sessions were randomly presented for dates, and sessions that were used in the practice training session were not presented again. A Daily Listening Record was kept as with the first judge. The second judge participated in three listening sessions of about four hours each, on different days, to complete the required listening. Refamiliarisation took place at the beginning of the two subsequent sessions. A comparison of the two judges’ intelligibility scores was made. The second judge was required to be a literate, native English speaker, under the age of 45, with normal speech and language skills and with no known medical condition or hearing loss that could affect performance.

The result was single word intelligibility scores collected for five subjects in a strictly controlled, replicable manner with the only variable for a subject being the timing of the introduction of respiratory therapy. Thus it should be possible to say if there is a change in the single word speech intelligibility for the MS subjects when respiratory therapy is given. There were minor variations in the procedures used between patients with one patient imitating the words rather than reading them or the judging format being multiple choice rather than transcription as was appropriate for!

reading ability or dysarthria severity for that subject. Obviously there was no