To determine speech intelligibility using the test suggested by Ozimek et al. (2009), the subject composed sentences with the words presented on a computer screen. However, the number and the type of these words were chosen arbitrarily. The subject was always presented with 18, similarly sounding words. Therefore, the aim of this study was to determine whether the number and the type of alternative words used by Ozimek et al. (2009), had a significant influence on the speech intelligibility. The aim was also to determine an optimal number of alternative words: i.e., the number that did not affect the speech reception threshold (SRT) and not unduly lengthened the duration of the test. The study conducted using a group of 10 subjects with normal hearing showed that an increase in the number of words to choose from 12 to 30 increased the speech intelligibility by about 0.3 dB/6 words. The use of paronyms as alternative words as opposed to random words, leads to an increase in the speech intelligibility by about 0.6 dB, which is equivalent to a decrease in intelligibility by 15 percentage points. Enlarging the number of words to choose from, and switching alternative words to paronyms, led to an increase in response time from approximately 11 to 16 s. It seems that the use of paronyms as alternative words as well as using 12 or 18 words to choose from is the best choice when using the Polish Sentence Test (PST).

The aim of the study was to determine the signal-to-noise ratio (SNR) for the Speech Reception Threshold (SRT) for young persons with normal hearing. The following three tests available for Polish language were used: the New Articulation Lists (NAL-93) version of 2011, the Polish Sentence Test (PST) and the Polish Sentence Matrix Test (PSMT). When using PST and PSMT the masking signal was babble noise made of the language material contained in the test. For NAL-93 the masking signal was speech noise. The speech reception threshold (SRT) was found to be (−6:8 ± 1.1), (−4:8 ± 1.6), (−3:5 ± 1.8) and (−3:4 ± 2.0) dB SNR for PST, PSMT, NAL-93 (constant stimuli method) and NAL-93 (short method), respectively. The values of SRT depend on semantic redundancy of the language material. Differences in SRT were statistically non-significant only for NAL-93 (constant stimuli method) and NAL-93 (short method). Moreover, it was shown that the time needed for presentation of a single word list (NAL-93, short method) or single sentence list (PST, PSMT) was comparable and equal to 2–3 minutes. The most uniform SRT values were obtained for PST. The PSMT was the least demanding for the listener, experimenter and equipment.

The main goal of the research was to obtain a set of data for ability of speech in noise recognition using Polish word test (New Articulation Lists – NAL-93) with two different masking signals. The attempt was also made to standardise the background noise for Polish speech tests by creating babble noise for NAL-93. Two types of background noise were used for Polish word test – the babble noise and the speech noise. The short method was chosen in the study as it provided similar results to constant stimuli method using less word material. The experiment using both maskers was presented to 10 listeners with normal hearing.

The mean SRT values for NAL-93 were −3.4 dB SNR for speech noise and 3.0 dB SNR for babble noise. In this regard, babble noise provided more efficient results. However, the SRT parameter for speech noise was more similar to values obtained for other Polish speech tests. The measurement of speech recognition using Polish word test is possible for both types of masking signals presented in the study. The decision as to which type of noise would be better in practice of hearing aid prosthetics remains an open-end question.