The design and validation of production of poly-syllabic words test in 4-7 years-old Persian speaking children: a preliminary study

abstract objective: Reviewing the literature related to the use of polysyllabic words in the assessment of children's speech sound disorders (SSD) indicated the necessity of using these words to provide additional information to the information of the more common tests, such as prognostic information. Despite strong literature background in other languages, there was not any research that examined production of these words in 4-7 years old children in Persian language, so the objective of this research was the design and validation of psychometric features of Persian (Farsi) version of polysyllabic words test for measuring production skills in preschooler children. method: In this cross-sectional research from methodological and test designing kind, First, 532 polysyllabic words (3, 4, 5 and 6 syllables) were selected from preschooler children books and reduced to 66 items by authors of this article in three rounds. Content validity of these selected items were examined by five typical speech development and SSD experts in terms of their appropriateness for examining polysyllabic words, for examining 4-7 years old children, imageability and cultural appropriateness. After selecting pictures, face validity of items and picture-name correspondence were examined by implementing of test on eight 4-7 years old children (at least one child from each age group). Finally, 40 items were considered as final words of polysyllabic words test. For measuring psychometric features, 120 typical children (4-7 years old, 60 males, 60 females), as well as 20 SSD children (10 males, 10 females) were investigated. Typical children were divided into 6 age groups with 6 months intervals and 10 males and 10 females were placed into each age group. Their inclusion criteria were that they should be in 4-7 years old range, they should not be bilingual and they should pass screening subtest of Persian DEAP (Zarifian 2014) and informal language screening successfully. Because of COVID-19 pandemic and closing of most preschooler children centers, sampling of typical children was based on availability from two regions of each city ( Tehran and Karaj). The inclusion criteria of SSD children were that they did not pass phonological and language screening successfully, they only had to be subject of Persian language and they not to have any disorder except SSD. Their sampling was based on availability.  For evaluating construct validity, significancy of differences among six age groups, between males and females and between typical children and SSD children were examined in terms of total score, PCC, PVC and PPC differences. Test-retest reliability was determined by reexamining of 20 children one week later, and inter-rater reliability was determined by investigation of relations between scores of two independent scorers in 20 children. The internal consistency was determined by investigating of correlations among test items. In this research, statistical central and dispersion indices, parametric tests of ANOVA and independent samples t-tests, tuckey test, Intra-Class Correlation and one statistical software (SPSS 26) were used. Results: Comparing of differences among age groups showed significant differences in terms of total score, Percentage of Consonants Correct and Percentage of Phonemes Correct (p< 0.001), but differences were not significant in Percentage of Vowels Correct (p= 0.23). No significant differences were found between males and females in terms of total score and correct percentages. Comparing of typical and SSD children showed that there were significant differences between two groups in terms of total score, PCC, PPC (p< 0.001) and PVC (p= 0.02). In examining reliability, Intra Class Correlation (ICC) was 0.98 in test- retest reliability, 0.79 in intra- rater reliability and amount of internal consistency was 0/75 for 3 syllabic words, 0/65 for 4 syllabic words and 0/63 for 5 syllabic words. Conclusion: Gained results from this research had conformity with similar research works, so Persian polysyllabic words test can be used as a valid and reliable instrument for measuring Speech production ability of 4-7 years old children in Sound Disorders and is applicable for clinical and therapeutical centers and research goals. The test has conformity with other tests (like Baker 2013) in terms of considering methodological principles like inclusion of a range of word lengths, syllable shapes and stress patterns of the target language, imageability, representing of common words of preschooler children and providing opportunities for eliciting common error patterns of the target language.