Objective: To evaluate an intervention programme based on the Health Action Process Approach and designed to increase the intake of fruit and vegetables (F&V) among Iranian adolescents aged 13 to 18.
Design: A randomised controlled trial with three arms examined the short- (1 month) and long-term (6 months) effects of the intervention. There were two intervention groups (one included adolescents only [A group; n = 510]; the second included mothers and adolescents [M + A group; n = 462]) and a control group (n = 483). All participants were recruited from schools.
Main outcome measures: Social cognitions, self-regulatory processes and F&V intake.
Results: The intervention led to an increase in F&V intake for adolescents in the short and long terms. Adolescents in the M + A group increased their F& V intake more than adolescents in the A group. Outcome expectancies, self-monitoring, intentions, action and coping planning, perceived social support and behavioural automaticity mediated the effect of the intervention on F&V intake.
Conclusion: The theory-based intervention led to an increase in F&V intake and promoted more positive social cognitions and self-regulatory processes among Iranian adolescents. The findings also provide evidence that involving mothers in an intervention can confer additional benefit. 相似文献
An experiment is reported in which participants at 6 (n = 20), 9 (n = 20), and 24 years (n = 20) of age either received or did not receive practice on a rapid aiming task using the arm and hand. The purpose of the experiment was to document the changes in movement substructures (in addition to movement time) as a function of practice. After receiving 10 baseline trials, subjects in the practice groups received 30 practice trials followed by 10 retention trials on each of 5 days, while subjects in the no-practice group had only baseline and retention trials. Retention-only trials were divided into primary (reflecting the ballistic controlled part of the movement) and secondary (reflecting corrective movement adjustments) submovements. In addition, jerk (the 3rd derivative of movement displacement) was calculated as an estimate of the smoothness of the movement. Participants increased the primary submovement as a function of practice; however, the increases were substantially larger in the children (25-30%) than in the adults (10%). Participants also decreased jerk as a function of practice and the decreases were greater in children than in adults. The results suggest that with practice the primary submovement is lengthened so that it ends nearer the target, especially in children. Associated with the primary submovement covering a larger percentage of the movement length and time, movements became smoother. 相似文献
Children and individuals with developmental disabilities (DD) compared to typical participants are disadvantaged not only by virtue of being vulnerable to risks inherent in research participation but also by the higher likelihood of exclusion from research altogether. Current regulatory and ethical guidelines although necessary for their protection do not sufficiently ensure fair distributive justice. Yet, in view of disproportionately higher burdens of co-occurring physical and mental disorders in individuals with DD, they are better positioned to benefit from research by equitable participation. Greater elucidation of this ethical dilemma is called for by researchers, institutional review boards, and funding agencies to urgently redress the imbalance. This article discusses many of the regulatory principles to ensure better research participation of children and individuals with DD: human rights, validity, distributive justice, beneficence/nonmaleficence, and autonomy. 相似文献
This article examines the theoretical basis of decision-making deficits exhibited by cocaine abusers in a laboratory decision-making
task first described by Bechara, Damasio, Damasio, and Anderson (1994). A total of 12 male cocaine abusers and 14 comparison
subjects performed the task, and the cocaine group performed significantly worse than the comparison group. A cognitive modeling
analysis (Busemeyer & Stout, 2002) was used to estimate three parameters that measure importance of the cognitive, motivational,
and response processes for determining the observed performance deficit. The results of this analysis indicated, for the first
time, that motivational and choice consistency factors, but not learning/ memory were mainly responsible for the decision-making
deficit of the cocaine abusers in this task. 相似文献
A problem with interpretations of differences in mathematic achievement between students from Asian countries and those from the United States is the seemingly implicit assumption of the cultural homogeneity of Asian societies. Researchers rarely measure the effects of variables within cultures that are hypothesized to be related to differences across cultures. In the present study, the authors examined the effects of socioeconomic status (SES) and quality of instruction on Chinese students' (1st, 3rd, and 5th grades) understanding of distance, time, and speed. The results indicated that (a) low SES in China can impede the development of children's mathematical cognition and (b) higher SES does not guarantee better performance. The implication is that the gap in mathematical performance between socioeconomically advantaged and disadvantaged children can be narrowed or even eliminated through instructional practices that focus on the systematic training of children's mathematical thinking. 相似文献