Scalogram Analysis of Aquatic Item Order in Young Adults

Guttman (1950) proposed a descriptive analytic instrument called a scalogram as a technique for identifying the optimal developmental or instructional order for a series of disparate tasks, referred to in the motor development literature as an “inter-task developmental sequence” (Haywood & Getchell, 205; Roberton & Halverson, 1984). Scalogram analysis successfully has been applied to the ordering of balance (DeOreo, 1976) and beginning swimming (Harrod & Langendorfer, 1990) items.

Purpose: The current study proposed to examine the robustness of task order (measured as the coefficient of reproducibility, or Cr) for a set of 13 diverse aquatic skills (e.g., breath control, floating, rudimentary front strokes, formal swim strokes) in order to identify whether the suggested order of presentation for these tasks was appropriate within a proposed revision of a learn-to-swim program for a prominent national agency.

Methods: A sample of 62 college-age young adults enrolled in university swimming instructional program were sampled on the 13 aquatic skill items with n=31 (f=17; m=14) completing the standard informed consent and attempting all test items. We videotaped each participant in stations performing each skill and subsequently rated each as having failed or passed each item according to the descriptor for that item.

Analysis/Results: Using Guttman's scalogram procedure, we created a reproducibility matrix that ordered individuals from those who passed fewest to most items and items from most individuals to fewest who passed them.

Conclusions: The Cr = 0.934, an exceptionally high coefficient of reproducibility, indicated that the proposed order of swimming items was in fact accurate and robust for young adults. The high coefficient likely was influenced by the relatively small sample size as well as the heterogeneous difficulty of the 13 test items. The study needs to be replicated with a larger adult sample and with at least one child sample.