Assessment of human obesity: The measurement of body composition

The most common methods of assessing degree of obesity in humans are reviewed. These include anthropometry, somatotyping, bodyweight, skinfold calipering, densitometry, and several nondensitometric procedures. The evidence suggests that bodyweight may often be an unreliable and invalid index of obesity. The parameters influencing its inaccuracy are discussed. These include age, height, sex, muscularity, and degree of obesity or amount of recent weight loss. The most reliable and valid measures of human bodyfat are generally the most complicated and impractical. Compromise assessment procedures involving nonintrusive measurement of subcutaneous fat and selected anthropometric dimensions may offer an incomplete but welcome improvement over sole reliance on bodyweight as an index of obesity.     

A study of orientation errors in response to Kohs-type figures(1)

In order to elucidate the nature of the orientation errors encountered when subjects are required to reproduce Kohs-type figures, subjects drawn from a culture where such errors are reported to be relatively common were required to reproduce orientation of simple figures. It was found that the responses made in the case of square figures showed a definite drift towards a “stable” orientation; the drift observed in the case of circular stimuli was too weak to permit an unambiguous interpretation. The relevance of these data to previous data on cross-cultural differences in responses to Kohs-type stimuli is briefly examined.     

Peer tutoring among elementary students: educational benefits to the tutor

To determine whether tutoring might be academically beneficial to the tutor, this study investigated the acquisition of spelling words by three elementary students in a peer tutoring program. The experimental design allowed a simultaneous comparison of each child's gain in performance on comparable word lists on which the child tutored another child, was tutored by another child, or neither gave nor received tutoring. The children's spelling improved nearly an equivalent amount on those words on which they tutored another child as on the words on which they were tutored; no such change was noted on the words on which they neither gave nor received tutoring. These findings, that peer tutoring is profitable for the tutor as well as the tutee, provide a basis for recommending peer tutoring as one method of individualizing education.     

Community applications of instructional technology: teaching writers of instructional packages

A community education program, to develop a variety of performance competencies in large numbers of neighborhood residents, requires a technology for preparing learning units administerable by community members themselves. The effects of a writing manual, designed to teach nonprofessionals to prepare such instructional packages, were analyzed in two experiments. Experiment I employed a multiple-baseline design across three university student trainees. The results showed that appropriate program writing increased by 75% after completion of the manual. The results of Experiment II, with two low-income neighborhood residents serving as trainees, showed that packages produced by trained writers resulted in a greater increase in skill activities than sets of training stimuli produced by untrained writers.     

Increasing engagement in activity of residents in old people's homes by providing recreational materials

This project investigated whether the level of engagement in two special Homes for the elderly could be increased by providing a regular recreational session, where the residents had the opportunity to use various extra recreational materials and to interact with the organiser of the session. The residents' level of engagement during the sessions was consistently higher than under baseline conditions. This indicates that the low engagement of the residents is at least partly due to lack of opportunity to engage, rather than to the specific disabilities of the residents. The methodological approach used in this study is suggested as a useful, objective way of evaluating the effects of, and preferences for, various types of recreational activities that might be offered to elderly people in residential care.     

Problems in assessment of vividness and control of imagery.

Difficulties in assessing individual differences in vividness and control of mental imagery hinder understanding of the role of of imagery in various phenomena. This study examined the relationships among the Gordon test of imagery control, the Betts questionnaire on imagery vividness, and a research questionnaire on control of imagery developed for this study. The research questionnaire demonstrated satisfactory internal consistency and scores were more widely distributed than were those on the Gordon test. Correlations among the instruments ranged from .47 to .57, suggesting that vividness and control of imagery are not clearly differentiated in practice. Discussion of these results suggests that further empirical work is needed to establish the differential validity of the two constructs.     

Transfer of reaction inhibition

A serious challenge to Hull's (1943) theory of reminiscence and intertrial-interval effects is posed by the current contention that reactive inhibition (In) must be task-specific since it does not seem to transfer from one task to another. This notion was examined within the framework of a practice-rest paradigm in which three control groups were given 20 1-min trials on a principal task with intertrial intervals of 0, 5, and 70 sec, respectively, while two experimental groups practiced alternately on the principal task and a secondary task known to produce evidence for I(R). The two secondary tasks varied in their similarities to the principal task. Additional control groups were used to assess the magnitude of habit transfer effects. The total sample consisted of 70 males and 70 females whose modal age was 18 yr. With habit transfer effects controlled, results showed clearly that work effects transferred from the alternate tasks to the main task without regard for differences in similarity. Thus, the task-specificity hypothesis was not supported.     

An analysis of motor coordination components for various localization tasks

Localization abilities of subjects in three perceptual-motor tasks were considered before and after an exposure to a visual distortion. During this distortion the subject observed his hand ballistically point to an invisible but audible target while either receiving or not receiving knowledge of results (KR) concerning pointing accuracy. Also, subjects either received a 1- or a 4-sec rest period between each of 30 exposure ballistic pointing actions. The pre- and postexposure tasks involved the ability of a subject to accurately point to an occluded and stationary auditory target, to point to the straight-ahead position in space, and to indicate when a moving, auditory target was perceived as being in the straight-ahead position. For these tasks, the pre- vs. postexposure localization difference scores are referred to as the negative aftereffect, the proprioceptive shift, and the auditory shift, respectively. Wilkinson's (1971) two-component additive model (negative aftereffect = proprioceptive shift plus auditory shift) held when KR was given regardless of amount of rest between exposure pointing responses. With a 4-sec rest and no KR, the relationship between coordination components was nonadditive (negative aftereffect greater than proprioceptive shift plus auditory shift).     

The influence of defensive styles upon the predictive validity of the Thematic Apperception Test

This study investigated the extent to which defensive styles of individuals influence the predictive validity of their responses to a projective test. College subjects (n = 34) were exposed to laboratory procedures which provided the basis for identifying preferred style of dealing with aversive self-relevant information. Those who demonstrated the tendency to deny negative information about themselves and attribute it to others (projectors) gave responses to selected Thematic Apperception Test cards which were positively correlated with dependency and achievement criteria. In contrast, those who tended to deny negative information by selective forgetting (repressors) provided projective test responses which were negatively correlated with the two behavioral criteria. Although statistical significance was not consistently achieved, the trend of results supported the validity of Thematic Apperception Test performance of projectors or nonrepressors and inverse prediction from the responses of repressors or nonprojectors.