The Connected Speech Test (CST)
 
Description:
The CST provides objective quantification of the intelligibility of connected speech. The user is encouraged to consult the references given about the development and administration of the test and reliability of data from normal-hearing and hearing-impaired listeners.

Briefly, the talker is a female who produces speech of average intelligibility. The multi-talker babble can be adjusted to simulate the signal to babble ratio (SBR) encountered in everyday listening situations. Each test item is a passage of speech, 9 or 10 sentences in length, about a familiar topic. The listener should be informed of the passage topic. Each passage is presented one sentence at a time. The passage score is based on the proportion of 25 scoring words correctly repeated. Scores typically are averaged across several test passages to produce a measure of intelligibility for a particular listening situation.

 
Purchase:
Obtaining the CST
Format: Audio Compact Disc
The CST is included on the HARL Speech Intelligibility Tests audio compact disc along with the Speech Intelligibility Rating Test (SIR Test). It may be used in a regular CD player for manual presentation or in computer-controlled CD-ROM. This format also allows random access to any sentence if you use a computer-controlled CD-ROM. However, it contains only the audio portion of the test (no video signal). To facilitate manual presentation of the test, brief pauses have been inserted between the sentences. Materials include a calibration noise for setting levels, a set of practice passages, a set of test passages, and some additional passages. All speech passages are recorded with the talker on the left channel and the competing babble on the right channel.

These tests were developed at the Hearing Aid Research Laboratory of The University of Memphis with primary support from the Department of Veterans Affairs Rehabilitation Research and Development Service. Support was also provided by the Center for Research Initiatives and Strategies for the Communicatively Impaired (CRISCI), The University of Memphis.

Cost: $50 (US) per disc

Format: Videodisc
Twelve-inch CAV optical videodisc for use with Sony, Pioneer and other similar videodisc players.

Cost: $200 per disc

Tips: If you plan to administer the test audio-visually and sentence-by sentence (the "standard" method), this is the best option because it allows random access to any sentence of any passage. We will supply frame numbers to locate passages and sentences as well as lists of scoring words. We cannot provide software. If you wish to control the videodisk player using a microcomputer, you would have to develop the software for your specific application and your specific hardware.

Format: DVD
TThe original video recordings of the Connected Speech Test passages have been transferred onto DVD. The CST test passages are organized into six-passage audio-visually equivalent sets as discussed in Cox, et al, (1989). This disk plays in a computer drive using Windows Media Player or in a stand-alone DVD player. The test is administered by manually pausing the disk between sentences using the space bar or the pause button. Scoring can be accomplished manually or using the software written for scoring the CD version.

Cost: $50 (US) per DVD

 

Purchase:
CST administration program
Format: CD

Cost: $30 (US)

Note: In order to use the software for scoring/administration of the CST you must have the CST audio CD and a CD-ROM drive on your computer.  It will not work with the videodisc.

 
References:
Information about the development and research regarding the CST may be found in:
Cox, R.M., Alexander, G.C., Gilmore, C. and Pusakulich, K.M. "The Connected Speech Test Version 3: Audiovisual Administration". Ear and Hearing, 10(1), 29-32 (1989).

Cox, R.M., Alexander, G.C., Gilmore, C. and Pusakulich, K.M. "Use of the Connected Speech Test (CST) with Hearing-Impaired Listeners". Ear and Hearing, 9(4), 198-207 (1988).

Cox, R.M., Alexander, G.C. and Gilmore, C.A. "Development of the connected speech test (CST)." Ear and Hearing, 8 (suppl): 119S-126S (1987).