Discriminative validity of the behavior assessment system for children‐parent rating scales in children with recurrent abdominal pain and matched controls

Examined discriminative validity of the Parent Rating Scale (PRS) of the Behavior Assessment System for Children (BASC; Reynolds & Kamphaus, 1992, Circle Pines, MN: American Guidance Services). Two groups were compared: a cohort with recurrent abdominal pain (RAP) (n= 49) and children from the BASC‐PRS standardization sample (n = 49) matched on the background characteristics of age, race/ethnicity, and gender. A multivariate, two‐group discriminant function analysis was used to compare groups across standard scores from the nine clinical scales of the PRS. Results demonstrated that children with RAP could be differentiated (Wilks λ = .642, F = 6.45, df (9, 88), p < .001), and demonstrated higher scores on the Somatization, Depression, Anxiety, Attention Problems, and Withdrawal scales. Subsequent jackknifed classification analysis, diagnostic efficiency statistics, and an odds ratio for the classification analysis added to the overall validity of results. The practical utility of the BASC‐PRS is further supported in light of expanding roles for school psychologists in the assessment and treatment of children with health problems. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 145–154, 2003.     

THE MARKOV CHAIN AS NULL HYPOTHESIS IN A DEVELOPMENT SURVEY1

Development criteria observed as time series on nominal variables pose a problem for research design. Markov chains are attractive in the first instance because they can handle such multivariate multinomial data sets, with results that are described and demonstrated on Career Development Study data. The power of the formal probability model is purchased at the expense of assumptions that may be unrealistic. It is argued and demonstrated that where the Markov chain theory for the data breaks down is precisely where the most interesting part of the message contained in the data resides. The Markov chain is shown to be a better null hypothesis against which to array the psychometric or other prediction model than is the usually employed random walk. A new prediction system that combines information from the Markov chain with the psychometric predictors is described and operated.     

Three-dimensional kinematic comparison of treadmill and overground running

The treadmill is an attractive device for the investigation of human locomotion, yet the extent to which lower limb kinematics differ from overground running remains a controversial topic. This study aimed to provide an extensive three-dimensional kinematic comparison of the lower extremities during overground and treadmill running. Twelve participants ran at 4.0 m/s ( ± 5%) in both treadmill and overground conditions. Angular kinematic parameters of the lower extremities during the stance phase were collected at 250 Hz using an eight-camera motion analysis system. Hip, knee, and ankle joint kinematics were quantified in the sagittal, coronal, and transverse planes, and contrasted using paired t-tests. Of the analysed parameters hip flexion at footstrike and ankle excursion to peak angle were found to be significantly reduced during treadmill running by 12° (p = 0.001) and 6.6° (p = 0.010), respectively. Treadmill running was found to be associated with significantly greater peak ankle eversion (by 6.3°, p = 0.006). It was concluded that the mechanics of treadmill running cannot be generalized to overground running.