Improving the measurement of spatial aptitude by dynamic testing

Can spatial aptitude scores be increased by test-related training? Is construct validity influenced? The traditional psychometric view of test-related training as coaching, which threatens test validity, contrasts sharply with the view that performance modifiability measures a theoretically important construct that increases test validity (e.g., Vygotsky, 1978). This article reports on three studies of the dynamic testing of spatial ability in which training on the physical analogue of the mental folding task intervenes between a pretest and a posttest. Experiment 1 found that spatial ability can be significantly and substantially increased. Experiment 2 examined the impact of the dynamic testing procedure on the relationship of ability scores to other measures. Although sex differences in spatial ability were unchanged, the dynamic testing procedure increased predictive validity for training in text editing. Experiment 3 examined the impact on construct representation. The mathematical models of task difficulty indicated that the posttest more clearly represented rotational processing while the psychometric models supported the measurement of two abilities (i.e., initial status and gain). The implications for measuring learning ability by dynamic testing are discussed.