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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Individual-Level and Clinic-Level Factors Associated with HPV Vaccine Initiation Among 11-17 Year Old Adolescents

Rodriguez, Serena Ann 16 November 2017 (has links)
<p> The human papillomavirus is the most common sexually transmitted infection, and persistent infection with oncogenic types can lead to cervical, anal, vaginal, vulvar, penile, and oropharyngeal cancers. HPV vaccination can protect against infection. However, vaccine series initiation and completion rates are below national goals. This dissertation aimed to identify individual- and clinic-level factors associated with HPV vaccination among adolescents aged 11-17 years to inform future interventions aimed at increasing vaccination and reducing HPV-related cancers.</p><p> This dissertation is in the form of three manuscripts each contributing to the overall aim. In manuscript 1, we conducted a systematic review of reviews identifying parental, provider, and clinic-level factors associated with HPV vaccination among adolescents. We synthesized findings from 12 reviews into a multilevel framework of HPV vaccination that can broaden our understanding of HPV vaccination and can inform future interventions by highlighting the relations between factors and potential intervention points. In manuscript 2, we examined correlates of parental intentions to vaccinate and parental psychosocial predictors of HPV vaccination for low income, underinsured Hispanic adolescent females. Findings can inform the development of targeted interventions for this population. In manuscript 3, we identified clinic characteristics and Consolidated Framework for Implementation Science Inner Setting constructs associated with HPV vaccine series initiation rates within a pediatric clinic network. Understanding clinic-level factors associated with vaccination can inform implementation of clinic systems and policies aimed at increasing vaccination rates.</p><p> Overall, these manuscripts contribute to the literature examining multilevel factors associated with adolescent HPV vaccination. Findings inform future multilevel interventions aimed at increasing HPV vaccination and targeting parent-, provider-, and clinic-levels.</p><p>
52

Teaching sequences of behaviors to humans by forward chaining, backward chaining, and whole task training.

Scott, Janine Mary. January 1990 (has links)
The three most common training methods of teaching sequences of behaviors are forward chaining, backward chaining and whole task training. In chaining methods, training involves gradually teaching the sequence by teaching increasingly longer subsequences until the entire sequence has been learned. In forward chaining, training involves gradually teaching the sequence from the beginning. Backward chaining involves gradually teaching the sequence from the end. Training is continued in this manner until the entire sequence is learned. Whole task training does not involve gradual learning. Instead, on each trial, the sequence is attempted in its entirety. Trials of this kind continue until the sequence is learned. It has been hypothesized that backward chaining is the superior method to teach sequences of behaviors because reinforcement is given at the end of each subsequence (Martin & Pear, 1988; Gilbert, 1962a & b). An example of this reinforcement would be the ball going through the hoop at the end of the sequence of behaviors involved in making a basketball shot. Random chaining consisted of teaching randomly chosen behaviors within the subsequences. Component behaviors were placed next to each other within the subsequence according to sequence order. Random-2 chaining was similar to random chaining except that the component behaviors were taught within the subsequences in the order in which they were selected. The final subsequence is an exception as it is the sequence taught in sequence order. Random-3 chaining was similar to random-2 chaining except component behaviors were selected with replacement. For each subsequence, selection starts fresh and the required number of behaviors are selected out of the eight possible behaviors. Whole task training produced more true errors than each chaining method except random-3 chaining. Random-3 chaining produced more true errors than forward, backward, random and random-2 chaining. No significant differences were found between random-3 chaining and whole task training. The results clearly did not support the hypothesis that backward chaining is superior to other training methods for the sequence of behaviors taught in the experiments. The discussion involves an analysis of the training methods into a number of factors which may influence their effectiveness and some suggestions for future research. (Abstract shortened by UMI.)
53

Aversive sign-tracking and backward conditioning.

Bernard, Diane. January 1989 (has links)
The present series of experiments tried to provide information about the associative value of the CS in backward conditioning and further our knowledge of approach behavior (APPR$\sp-$) towards a CS which signals absence of an aversive US. In all experiments, the US was a foot-shock (.5 mA, 2 sec) and the CS was a platform accessible for short time periods each trial. Time spent on the platform was used as a measure of APPR$\sp-$ behavior. Experiment 1 compared the effects of backward, differential, and explicitly unpaired procedures with a random procedure on the development of APPR$\sp-$ behavior. The results showed rapid acquisition of APPR$\sp-$ behavior in each of the experimental groups in comparison with the random group. In a subsequent retardation-of-acquisition test (forward pairings), all experimental groups showed gradual suppression of APPR$\sp-$ behavior, suggesting conditioned inhibition to the platform-CS in each of the experimental groups. Experiment 2 studied the effect of the number of backward pairings on APPR$\sp-$. The results showed that five or ten daily pairings were sufficient for the rapid acquisition of APPR$\sp-$ behavior, while one daily pairing produced WDR$\sp+$ behavior (a behavioral tendency opposite to APPR$\sp-$ behavior). In a subsequent retardation-of-acquisition test, the experimental group exposed to five daily pairings showed rapid suppression of APPR$\sp-$ behavior. These results were interpreted in terms of possible differential level of conditioned inhibition to the CS produced by differential number of US-CS pairings. Experiment 3 studied the effect of ITI lengths on the development of APPR$\sp-$ behavior in backward conditioning. A strong APPR$\sp-$ behavior was observed when the ITI range was long (2 to 4 min), but not when ITI range was sometimes short (10 sec) and sometimes long (5 min). These results showed that the CS must reliably signal a relatively long period without shock for the development of APPR$\sp-$ behavior. In Experiment 4, conditioned inhibition to the CS in backward pairings was evaluated independently of APPR$\sp-$ behavior, in the context of a conditioned suppression paradigm. The results showed that US-CS pairings procedure produced less suppression of drinking than CS-US pairings, but no response acceleration in comparison with the control condition. Time spent on the platform and behavioral observations failed to provide evidence of the inhibitory properties of the CS in the backward conditioning group possibly due to extinction during testing sessions. In conclusion, it seems that under specific conditions, the CS in backward conditioning acquires inhibitory associative value and a conditioned inhibition mechanism would be partly responsible for APPR$\sp-$ behavior. However, temporal contiguity seems to be an essential element to APPR$\sp-$ behavior. At a theoretical level, a modified stimulus substitution model could be considered as an alternative to a contingency model explaining APPR$\sp-$.
54

Une analyse motivationnelle de la régularisation du comportement alimentaire.

Dion, Stéphanie C. January 2002 (has links)
Le but de cette thèse était d'examiner, à l'aide d'une approche motivationnelle, pourquoi certaines femmes, bien qu'insatisfaites de leur image corporelle présentent un comportement alimentaire sain alors que d'autres manifestent un comportement alimentaire dysfonctionnel. La motivation a été évaluée à deux niveaux: un niveau global et un niveau spécifique. Le niveau global correspondait à la motivation des femmes à régulariser les différentes activités de leur vie en général, alors que le niveau spécifique correspondait à la motivation des femmes à régulariser leur comportement alimentaire. Au total, quatre études ont été effectuées auprès d'étudiantes à l'Université d'Ottawa. Les résultats de la première étude ( N = 299) ont révélé que l'ajout du niveau d'autodétermination global contribuait significativement à l'explication de pourquoi certaines femmes, bien qu'exposées aux divers messages socioculturels concernant l'image corporelle, sont moins influencées par ceux-ci et moins susceptibles de présenter des symptômes de boulimie. Lors des deuxième ( N = 335) et troisième ( N = 339) études, nous avons procédé au développement d'une version expérimentale de l'Échelle de Régularisation des Comportements Alimentaires (ERCA) qui permet la mesure des six styles de régularisation comportementale proposés par Deci et Ryan (1985, 1991) dans leur théorie de l'autodétermination. Un modèle portant sur les relations entre deux formes globales de régularisation alimentaire (autonome et contrôlée), deux types de comportement alimentaire (sain vs. dysfonctionnel), et l'ajustement psychologique a été évalué par le biais d'analyses par équations structurelles. Globalement, les résultats ont révélé qu'une forme de régularisation alimentaire autonome était associée positivement à un comportement alimentaire sain, lequel était positivement associé à l'ajustement psychologique. Par ailleurs, une forme de régularisation alimentaire contrôlée était associée positivement à un comportement alimentaire dysfonctionnel, lequel était négativement associé à l'ajustement psychologique. Lors de la quatrième et dernière étude ( N = 442), un modèle intégratif de la régularisation du comportement alimentaire a été proposé et testé. Entre autres, dans ce modèle, les deux formes globales de régularisation alimentaire (autonome vs. contrôlée) ont été proposées comme mécanismes motivationnels permettant de mieux comprendre la nature des relations entre l'insatisfaction corporelle et deux types de comportement alimentaire (sain vs. dysfonctionnel). Globalement, les résultats d'analyses par équations structurelles ont suggéré que le niveau d'autodétermination global est associé à la façon dont les femmes régularisent leur comportement alimentaire, ce qui est relié à des comportements alimentaires qualitativement différents. Ces comportements alimentaires, à leur tour, sont reliés à l'ajustement psychologique de la personne. Finalement, le niveau global d'autodétermination est négativement associé aux influences socioculturelles concernant l'image corporelle. Les résultats sont discutés en termes de leurs implications théoriques et pratiques. Des pistes de recherches futures sont également proposées.
55

Associations between mothers' and daughters' physical activity behavior, motivation, and body image perceptions: A multi-method study.

Thom, Julie D. January 2001 (has links)
The purpose of this thesis was to examine the associations among mothers' and daughters' physical activity behavior, motivation and body image perceptions using a multi-method approach. Phase 1 of this study was quantitative, and served to investigate the relationships between mothers' and daughters' physical activity behavior and motivation. Social Learning Theory (Bandura, 1977) and the Deviancy Model (Jessor & Jessor, 1977) were both used in order to investigate mother-daughter activity behaviors. For Phase 1, three groups were established based on the mothers' scores from the questionnaire: non-, moderate and high frequency exercisers. In order to further examine the mother-daughter relationship and specifically to investigate body image perceptions, a second qualitative phase (Phase 2) was conducted. Phase 2 consisted of interviewing 10 mothers and daughters (5 mother-daughter pairs). For this phase, a semi-structured interview guide was developed to further assess motivation and body image perceptions of both the mothers' and daughters'. Also, a Body Esteem Scale (Mendelson, White & Mendelson, 1997--98) was administered to the interviewees before conducting the interview. (Abstract shortened by UMI.)
56

The influence of assuming and role-playing a false identity on event-related potentials.

Deck, Trevor Paul. January 2002 (has links)
Identity schemata serve to organize the content and regulate the processing of identity related information. The dissimulation of undercover agents and others has been associated with fundamental changes in the mental schemata and cognitive structures associated with their identity. This processing of identity information can be can be detected and quantified through Event Related Potentials (ERP). The purpose of the study was to compare the P300 ERPs in persons predisposed and not predisposed to dissociative experiences as they responded to factual (real) and counterfactual (false) personal identity information when asked to be themselves or dissimulate their real identity by adopting a false one. The interest was in examining whether information previously irrelevant to one's self-identity would be seen as meaningful when participants cognitively adopted a false identity and when they engaged in social-behavioural role-plays of that false identity. The degree to which the false identity was seen as meaningful was expected to vary as a function of scores on the Dissociative Experiences Scale (DES). Male students (19--24 yrs), 18 scoring high and 17 scoring low on the DES chose among three fabricated identities one they were to assume for the study. Eighty words representing their chosen false identity, their real identity, and two irrelevant identities served as stimulus items in a self-referencing task. ERP recordings from frontal, central, and parietal sites were obtained under four conditions. A pre-test of ERPs to all stimuli was followed by a second presentation where subjects assumed a false identity and denied their real identity. Subjects then participated in three semi-structured role-play interactions while assuming their false identity over a 3--5 day period. ERP recordings while assuming their false identity and again while assuming their real identity were subsequently obtained. P300 ERPs were elicited to real identity and to false identity information when subjects assumed one or the other. Importantly, previously obtained P300 responses to real identity stimuli were suppressed when ERPs to false identity stimuli were obtained. Role playing diminished P300 to a false identity. High, compared with low scoring, amnesia subjects of the DES were less able to suppress ERPs to their real identity when adopting a false identity. Results are discussed in relation to identity schema theory, dissociative disorders, with implications for undercover policing.
57

Condom use among heterosexual couples.

Edgley, Krista. January 2002 (has links)
To further understand the predictors of condom use for HIV prevention, this cross-sectional study surveyed 276 heterosexually active couples, between the ages of 16 and 29, who had been dating for less than one year. Each partner completed a self-report, multidimensional survey package and returned it via mail. Study objectives were to examine: (1) whether variables previously associated with condom use in studies of individuals (i.e., communication, attitudes toward condoms, knowledge, relationship variables), were associated with condom use in the context of the couple relationship; (2) whether there were paired-gender differences on the predictor variables; and (3) whether attachment style was associated with condom use among the couples sampled. The unique and innovative aspects of the study were its focus on couples and its exploration of the influence of attachment. The study yielded several important results. First, congruence of partner scores regarding the perception of need for condoms safe relationships was of particular importance in predicting the likelihood of condom use. Consistent condom use was more likely to occur if both partners held a positive perception; inconsistent or non-condom use was more likely if both partners held a negative view. Second, the variables that had been previously identified as predictors in studies of individuals, taken together, helped to correctly classify inconsistent/no-condom use, but did not do so for consistent use. Third, although females reported asking questions about their partner's sexual history more often than did males, and also reported carrying the burden of the decision to use condoms, their decision was ultimately influenced by their male partner's perception of whether condoms should be used. Finally, although there were no significant relationships between attachment style and condom use, it is not possible to rule out the absence of an association owing to the inadequate representation of all attachment styles in this sample. Furthermore, significant correlations were observed between condom use predictor variables and attachment working models that represent the individual's image of other people, and the individual's image of self. Results are discussed with respect to decision-making heuristics and optimistic bias regarding HIV/STD risk perceptions, and implications for intervention strategies are suggested.
58

An investigation of the application of self-determination theory to potentially problematic behaviours. Test of an illustrative model: Gambling behaviour.

Keyes, Marilyn T. January 2002 (has links)
The purpose of this research was to first, investigate the application of Deci and Ryan's (1990) Self-Determination Theory (SDT) to a potentially problematic behaviour, and second, to investigate the relationship between gambling motivation and consequences. The SDT framework has been used to investigate the relationship between motivation and consequences in domains considered to be functional activities and to have positive consequences. It is unknown whether postulates of the SDT can be extended to activities that are potentially problematic and therefore may be associated negative consequences. The domain of gambling was chosen for this research because of its growing popularity and awareness of the negative consequences that can be associated with this behaviour. Vallerand's (1997) hierarchical model of self-determination and the previously investigated domain of leisure were incorporated into a gambling model to allow comparison of the results of this study with results previously found in other populations. A pilot study explored the relationships between gambling motivation and gambling consequences. The Gambling Motivation Scale (GAMS; Chantal, Vallerand, & Vallieres, 1995), the South Oaks Gambling Screen (SOGS; Lesieur & Blume, 1987), the Rosenberg Self-esteem Scale (RSE; Rosenberg, 1979) and the Self-Rating Depression Scale, (Zung, 1965) were completed by 237 men and women from the general and university populations. Results did not completely support or refute the tenets of Self-Determination Theory. Study 1 tested a hierarchical model of leisure and gambling activities, headed by global self-determination, in a sample of men and women (N = 215) who had gambled in the last year. Respondents completed the Global Self-Determination Scale (Quay, et al., 1996), the Leisure Motivation Scale (Pelletier, Green-Demers & Dion, 1998), the GAMS, a measure of leisure activity consequences, the SOGS, the RSE, the Centre for Epidemiologic Studies Depression Scale (Radloff, 1977) and the Satisfaction with Life Scale (Diener, Emmons, Larson, & Griffin, 1985). Based on SOGS scores, 16.6% of the sample met criteria for possible problem gambling. Results from structural equation modelling analysis (with LISREL) support the use of Vallerand's (1997) hierarchical domain specific theory and SDT in research with adaptive behaviours. Results of the gambling side of the model provide limited support for the use of these theories in research with potentially problematic activities. There is some evidence that motivation plays a role in the development of problem gambling and that global self-determination moderates the relationship between gambling involvement and problem gambling.
59

Summary measures for assessing the risk of a new disease: The case of the sexual transmission of HIV.

Declich, Silvia. January 1994 (has links)
The overall goal of this work is to critically assess and clarify methodologies for risk assessment and summary measure development which may be useful in appraising the risk involved in sexual transmission of HIV. The source of information for the available methods for risk assessment which various disciplines have developed, was a systematic review of the literature, the raw material being papers containing indexes assessing risk. Papers containing information about the development procedure were selected and sorted into reasonably homogeneous groups, which resulted in the proposal of a classification for risk assessment methods. The proposed classification identified the following methods: (1) the empirical method, which relies on collected data; (2) the judgemental method, which is based on the opinions of experts; (3) the psychometric method, which is built on a theoretical hypothesis about the construct; and (4) the mathematical method, which is based on an abstract representation in mathematical form of the phenomenon under study. A strategy similar to the one used in the search for risk assessment methods was employed in the search of the literature for existing indexes for the risk of HIV due to sexual behaviour. A logical progression of methods over time is evident, with the mathematical method as a foundation of risk assessment, followed by the psychometric method supported by a theoretical hypothesis, and finally, the judgemental and empirical methods, which require a sufficient amount of experts' knowledge and empirical data, respectively. The assessment of risk for HIV infection seems to be reaching the final stage of this progression. (Abstract shortened by UMI.)
60

An examination into the relationship between the attention deficit hyperactivity disorder and aggression.

Rynard, David William. January 1991 (has links)
Recent research indicates that the presence of aggressive behaviour in boys diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) is related to a poorer prognosis, different etiological factors, interpersonal problems, and the selection of appropriate treatment components than ADHD without aggression. Unfortunately, many studies examining various deficits thought to be specific to ADHD children have failed to utilize data from different diagnostic sources to allow for comparisons between attention/overactivity and aggressive symptomatology. The present investigation utilized a between groups comparison design with group assignment based on a two step-multisource inclusion criterion (DICA-P Interview and IOWA Conners) to make comparisons across four groups: hyperactive-only (IO, N = 12), aggressive-only (AGG, N = 16), hyperactive/aggressive (IO/AGG, N = 35) and normal controls (N = 33). Subjects were compared on parent and teacher rating scales and interviews, laboratory measures of vigilance, impulsivity, higher-order learning/memory, family functioning, general and social attribution, and self-report ratings. The results of this study partially support the use of parent and teacher rating scales in making distinctions between aggressive and hyperactive children. In agreement with previous studies, mothers of boys in the AGG and IO/AGG groups described a greater number of depressive, anxious, oppositional behaviours, and family psychosocial stress than did mothers in IO and Control groups. All clinical groups were rated by parents and teachers as displaying a higher frequency of disruptive and impulsive behaviours, and peer-related difficulties. Discriminant analyses on parent and teacher ratings revealed that boys in the AGG and IO/AGG group were the most similar in terms of symptomatology. Prediction on scales of the separate rating and interviews was best for IO and Control groups. The IO/AGG received the highest ratings on parent and teacher rating scales. In contrast to the predictions made between experimental groups, the IO/AGG subjects displayed only some common characteristics with IO subjects. IO subjects displayed more evidence of cognitive dysfunction on the high-order learning task and Delay task of the Gordon Diagnostic System (GDS). The lack of reliable group differences on the GDS Vigilance task and Efficiency Ratio of the Delay task questions the validity of the GDS in the diagnosis of ADHD and highlights the importance of designing new tasks to assess impulsivity and attention which hold important social/motivational and age-related factors constant. Predicted group differences were also not evident on the Beitchman self-report rating or general attribution questionnaire. All clinical groups described greater rigidity in family interactions and were more likely to display evidence of social information processing biases than control subjects. Overall, these results suggest that the ADHD category includes a heterogeneous group of behaviour disordered boys, and that further study into the cognitive, social, familial, and attributional styles of aggressive and hyperactive boys warrants continued exploration.

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