On repeated measures designs: hierarchical structures and time trends

The basic anatomy of an experimental design is used as an expository introduction to the examination of several repeated measures experiments described in recent pages of this and other journals. This examination reveals problematic issues concerning some common design and analysis features of such experimental designs. In particular, the hierarchical structures and/or presence of time trends is highlighted. These issues are discussed in an attempt to assist researchers to recognize such problems, to avoid the associated difficulties in the future, and to exploit the advantages of sound design with appropriate, efficient and informative analysis. While alternate reanalyses of the data of these experiments might reveal the conclusions to be unaffected by such issues, researchers should still be cautious. In retrospect, such occurrences should be seen as fortuitous, not as justification for inefficient or less informative analyses. More importantly, such reanalyses could reveal more enlightening information, and I argue that if a design permits such information to be discovered, then it behoves researchers to perform such analyses and to make such discoveries.     

The effect of warm up on single and intermittent-sprint performance

Lack of benefit of warm up on prolonged intermittent-sprint performance has been proposed to be due to use of a pacing strategy by participants. To investigate this, twelve participants performed four cycle trials that consisted of either prolonged intermittent-sprint performance (80 min) or single-sprint performance (4 s), with or without a warm up. The first-sprint of intermittent-sprint performance was also assessed. No interaction effects (P > 0.05) were found between trials for intermittent-sprint performance for total work (J · kg(-1)), or percentage work and power decrement. Work done during the first-sprint of intermittent-sprint performance (no warm up) was less (P < 0.001) than the first-sprint of intermittent-sprint performance (warm up; effect size (ES) = 0.59) and both single-sprint trials (warm up and no warm up; ES = 0.91, 0.75, respectively). Peak power (W · kg(-1)) for single-sprint (warm up) was greater (P < 0.05) than single-sprint (no warm up), and the first-sprint of intermittent-sprint performance (warm up and no warm up). Warm up improved single-sprint performance and the first sprint of intermittent-sprint performance. Use of a pacing strategy probably resulted in similar intermittent-sprint performance between trials. These results suggest that team-sport players should perform a warm up at the start of a game or before substitution during a game.     

Students with autism in regular classes: a long-term follow-up study of a satellite class transition model

Students with autism spectrum disorders (ASDs) are increasingly being educated within mainstream schools. While there is often an assumption that students with ASD who are academically capable will succeed in an inclusive educational placement, previous research has indicated that this is not always the case. Indeed, it seems that students with ASDs are often not equipped to cope with the social and communication demands of a mainstream classroom. Autism Spectrum Australia's (Aspect) satellite class programme aims to address this gap by blending specialised intervention with strategies to prepare students and receiving schools for transition to more inclusive educational placements. A long-term follow-up study comprising a parent survey of satellite class graduates and four detailed case studies was undertaken to determine whether these classes led to successful placement of students with ASD in more inclusive educational settings. Results indicated that a majority of graduates remained placed in more inclusive educational settings. Overall, parents were satisfied with the programme. Attendance at a satellite class was just one of a number of factors associated with positive outcomes in late adolescence. These findings are discussed in terms of their implications for teachers and school staff planning for and supporting students with ASDs in their transition to inclusive educational settings.