Purpose of the Questionnaire (Scale)

The GPVT (Greek Picture Vocabulary Test) was designed for the assessment of vocabulary and language development in children and adolescents of the Greek-speaking population. It is intended for professionals such as educators, speech therapists, and clinical psychologists, with the primary aim of measuring the ability to recognize and understand words through visual stimuli. The test is used for the detection of dyslexia, language delays, and for monitoring language development.

Questionnaire (Scale) Analysis

The GPVT was developed by Papageorgiou and Sideridis (1999) and includes 120 pictures representing basic and complex words of the Greek vocabulary. The pictures cover categories such as familiar objects, animals and plants, professions and activities, as well as abstract concepts. Each picture is accompanied by multiple verbal options, from which the examinee selects the correct match.

Scoring of Questions

Each correct answer is scored with 1 point, with a maximum possible score of 120 points. The final score is converted into a standardized score according to age norms. In addition, separate scores are provided for each word category, allowing for a differentiated assessment of language skills.

Statistical Analysis

The test has been standardized on a sample of 1,200 Greek-speaking children aged 4–16 years. Statistical indicators show high internal consistency (α = 0.92) and stability (test-retest reliability r = 0.89). Correlations with other language assessment tools range from 0.75 to 0.82, confirming its validity.

Validity of the Questionnaire (Scale)

The validity of the GPVT has been confirmed through multiple methods. It demonstrates high content validity, as verified by expert review. Its convergent validity is demonstrated by a strong correlation (r = 0.78) with the Verbal IQ of the WAIS-III. In addition, the test effectively distinguishes between children with and without language difficulties.

Reliability of the Questionnaire (Scale)

The tool demonstrates excellent reliability, with internal consistency indicators (α = 0.92) exceeding commonly accepted thresholds. Stability in repeated measurements (r = 0.89) and high inter-rater agreement (>90%) confirm its reliability for clinical and research use.

References

Greek References
Papageorgiou, I., & Sideridis, G. (1999). Greek Picture Vocabulary Test: An assessment tool for language ability. Scientific Yearbook of the Hellenic Psychological Society, 5(2), 33–45.
Foreign References
Sideridis, G., & Papageorgiou, I. (2002). Cross-cultural adaptation of vocabulary assessment tools. Journal of Cross-Cultural Psychology, 33(4), 456–472.

Keywords

Language assessment, vocabulary, language development, dyslexia, speech therapy, psychometric tools, Greek vocabulary.