Purpose

The purpose of the questionnaire, according to the Spatial Perception Test (SPT), is to assess an individual’s spatial perception ability. Spatial perception refers to the individual’s capacity to understand and manage spatial relationships, as described in Lohman’s theoretical model (1979).

Scoring

The Spatial Perception Test (SPT) measures specific spatial abilities through 36 items, which are categorized into three main skill areas:
Mental Rotations
Imagined Orientation
Reversal of Mental Images
The items included in the final version of the test were selected using Item Response Theory (IRT) and the Rasch model, ensuring accuracy and reliability. Evaluation can be conducted on two levels: subscale level and total score level. In both cases, scoring is based on the total number of correct responses per subscale and in the overall test.

Sample

To establish norms for the Greek population, the SPT was administered to 694 individuals from various regions across Greece. Available norms are expressed in percentiles and T-scores. The means and standard deviations for the different age groups are:
Mental Rotations: Mean = 6.67, SD = 1.11
Imagined Orientation: Mean = 6.42, SD = 1.05
Reversal of Mental Images: Mean = 4.11, SD = 1.26
Separate scores are available for boys and girls.

Validity and Reliability

The SPT demonstrated satisfactory correlations with two other tests measuring similar traits from General Abilities batteries (r = 0.52 to 0.65) and Verbal-Graphic Ability (r = 0.36 to 0.56). In terms of convergent validity, it showed moderate correlations with the Raven’s Progressive Matrices (r = 0.20 to 0.53), while discriminant validity yielded very low (r = 0.16 to 0.27) or no correlations (r = 0.07 to 0.17) with two tests measuring numerical reasoning and verbal similarity.
Two indices were used to assess the reliability of the SPT:
Kuder-Richardson coefficient for internal consistency: 0.85
Test-retest reliability coefficient: 0.84
Both indicate strong reliability.

Primary Reference

Tsaousis, I. (forthcoming). Measuring Spatial Perception Ability: The Development and Psychometric Properties of the Spatial Perception Test (SPT). Psychologia.