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G Kok

Publications and source records attributed to G Kok.

At least 37 records · Page 2Linked to original sources
PubMed1998

Effectiveness of a personalized Health Profile for blue-collar workers.

This article describes a study on the effectiveness of a Health Profile that was offered to blue-collar workers. The major goal of the Health Profile was to improve workers' awareness of own health behaviors and their intentions to change unhealthy behaviors. The Health Profile consisted of a booklet in A4-format in which tailored information was given on health behaviors. A pretest and posttest design (no control group) was used. The results showed a significant improvement of awareness of own health behaviors. Significant attitudinal changes were also achieved. There were no changes in social support and self-efficacy nor was there a change in the intention to change behaviors. These results suggest that a personalized Health Profile is a promising means to make workers aware of their personal risk behaviors.

Adult↗
PubMed1998

The impact of computer-tailored feedback and iterative feedback on fat, fruit, and vegetable intake.

A randomized trial was conducted to study the impact of individualized computer-generated nutrition information and additional effects of iterative feedback on changes in intake of fat, fruits, and vegetables. Respondents in the experimental group received computer-generated feedback letters tailored to their dietary intake, intentions, attitudes, self-efficacy expectations, and self-rated behavior. After the first feedback letter, half of the experimental group received additional iterative feedback tailored to changes in behavior and intentions. The control group received a single general nutrition information letter in a format similar to the tailored letters. Computer-tailored feedback had a significantly greater impact on fat reduction and fruit and vegetable intake than did general information. Iterative computer-tailored feedback had an additional impact on fat intake. The results confirm that computer-generated individualized feedback can be effective in inducing recommended dietary changes and that iterative feedback can increase the longer term impact of computer-tailored nutrition education on fat reduction.

Adult↗
PubMed1998

Intervention mapping: a process for developing theory- and evidence-based health education programs.

The practice of health education involves three major program-planning activities: needs assessment, program development, and evaluation. Over the past 20 years, significant enhancements have been made to the conceptual base and practice of health education. Models that outline explicit procedures and detailed conceptualization of community assessment and evaluation have been developed. Other advancements include the application of theory to health education and promotion program development and implementation. However, there remains a need for more explicit specification of the processes by which one uses theory and empirical findings to develop interventions. This article presents the origins, purpose, and description of Intervention Mapping, a framework for health education intervention development. Intervention Mapping is composed of five steps: (1) creating a matrix of proximal program objectives, (2) selecting theory-based intervention methods and practical strategies, (3) designing and organizing a program, (4) specifying adoption and implementation plans, and (5) generating program evaluation plans.

Decision Support Techniques↗
PubMed1997

Dual infections of PRRSV/influenza or PRRSV/Actinobacillus pleuropneumoniae in the respiratory tract.

To study the effect of a previous porcine respiratory and reproductive syndrome-infection (PRRS) of the respiratory tract on influenza virus and Actinobacillus pleuropneumoniae (App) infections, 3-week-old specific-pathogen-free (spf) piglets were intranasally infected with PRRS virus. One week later, when the lung alveolar macrophages of PRRSV infected pigs were lowest in number, a second infection was applied by intranasal aerosol of influenza virus H3N2 or by endobronchial instillation of a mildly virulent App. The first experiment consisted of two groups (only influenza infection or dual PRRSV/influenza infection). A second experiment consisted of 4 groups (only influenza infection, only PRRSV infection, dual PRRSV/influenza infection and uninfected controls). At day 2, 4, 14 and 21 after influenza infection, two pigs were killed and sampled for virological and histopathological examination. Influenza H3N2 virus caused only a mild inflammation of the smaller bronchioli. Previous PRRSV infection did not influence clinical signs during influenza infection. Next, we studied in two experiments the effect of dual PRRSV/App infection during the acute stage at two days after App infection. In a third experiment, the influence of PRRSV on more chronic stages of App infection was studied at two weeks after the App infection. At the end of the experiments, the pigs were killed. Lungs were ranked according to size and kind of the lesions. Lesions were cut and measured, samples were taken for virological and histopathological examination. Statistical analysis of the ranked lung-lesions in the first experiment showed a distinct but small effect of previous PRRSV infection on the development of App-lesions. In PRRSV infected pigs. App produced a more severe disease. The second and third experiment however failed to show any influence of the previous PRRSV infection on the App infection. We conclude that previous PRRSV infection of the respiratory tract of spf pigs does not necessarily enhance the severity of secondary infections of the respiratory tract.

Actinobacillus Infections↗
PubMed1997

Effectiveness of health education and health promotion: meta-analyses of effect studies and determinants of effectiveness.

Interventions to promote health that have been developed over the last 20 years in the relatively new scientific health education tradition, have often been evaluated for their effectiveness. Meta-analyses of effect studies on various subfields, show that these interventions generally have quite substantial effects (mean effect sizes, ES, of 0.46 for primary prevention and 0.49 for secondary prevention and patient education). A planned and systematic application of social science theory in intervention development is a strong determinant of effectiveness. However, learning principles such as rewards and feedback, that have been shown to increase effectiveness, are often not or not adequately applied. Also, too few interventions focus on possibilities to facilitate the desired behavior (such as reminders, financial stimuli, and skills improvement). The potential effectiveness of interventions in practice may be increased by systematic development of adoption and implementation strategies, including the creation of 'linkage systems' between intervention developers and representatives of the target and user systems.

Health Behavior↗
PubMed1997

Cues to action in the process of changing lifestyle.

This research has been carried out in order to evaluate cues to action in health behavior. Which cues produce changes and how does the process of change proceed? In-depth qualitative interviews based on the Grounded Theory Method were made with 21 40-year-old men. Ten men were interviewed three times during a 1-year period to trace the process of change. In total 40 interviews were carried out during 1989-1990. All the interviewees were randomly selected from the population registers in the municipalities of Aarhus and Vejle. The main themes of the interviews are changes in previous health behavior, motivation for intentions to change in health behavior, and the role of health education in the process of change. Health behavior determinants seem to be knowledge, attitude, confidence, social influence, experiences and possibilities for change. Individuals typically exhibit a wide range of these determinants which makes it difficult to affect behavioral change through health education. Cues to action seem to arise from social influence, experiences, or underlying shifts in the possibilities of change. Experiences and social influence due to the health behavior in question seem to initiate changes in confidence, attitude and thereby motivation to change. Cues to action arising from these determinants are categorized as own illness or illness among friends and relatives, changes in self-perception, exceeded limits determined by the behavior in question, and social pressure. Shifts in the possibilities for change, such as change of partner or other life events, produce changes also affecting health behavior. A strategy to initiate changes in health behavior could be to create cues to action through personal experiences in the context of a specific health behavior or to establish contact to people when they are experiencing new life circumstances.

Adult↗
PubMed1997

Nutrition education interventions in a community setting: 2 Dutch examples.

This article presents the results of two studies among participants of two Dutch nutrition education interventions, i.e. a self-help program and a living room group session. Both interventions aim to reduce fat intake in the general population and were developed as part of the Dutch community health project 'Healthy Bergeyk'. The objectives of the studies were to assess number of participants, participant characteristics, use of the self-help program, participant satisfaction and self-reported effects. Telephone interviews and written questionnaires were completed by inhabitants after participating in the interventions. The results are encouraging and the interventions seem to be useful as part of community projects.

Adult↗
PubMed1997

A pre-intervention survey to determine understanding of HIV and AIDS in farm worker communities in Zimbabwe.

A cumulative total of 41,298 AIDS cases have been reported in Zimbabwe as of March 1995. Of concern is the growing evidence of high levels of seroprevalence among rural farm workers. A pre-intervention survey was conducted by interview in one district to examine behavioral factors likely to place farm workers in marginalized rural communities at risk for sexually transmitted diseases (STD) and HIV infection. Seven hundred seventy commercial farm workers from 17 randomly selected commercial farm participated in the study. We found that farm worker communities, which are characterized by educationally disadvantaged women when compared with men (p < .001), have had little exposure to AIDS prevention activities. Beliefs that AIDS is brought about by divine or ancestral retribution were upheld by less education women (p < .001). A significant association was found with respect to perceived risk to HIV and low self-efficacy among uneducated women who articulated helplessness and an inability to protect themselves from HIV infection. Among more educated men, we found acknowledgment about multipartnering and that changes in behavior are more likely to develop as a result of changes in normative values (p = .075). Condom use among men, which is probably the most effective barrier against STD infection, was shown to be associated with age (p < .01) and education (p < .01). The study concludes with recommendations for an appropriate intervention.

Adolescent↗
PubMed1996

Patients' perceptions on informed consent and the quality of information disclosure in clinical trials.

In a survey on 26 clinical trials we studied how patients experience and evaluate the information disclosure on the clinical trial they are enrolled in and which factors influence patients' perceptions of information disclosure. Our objective was to obtain more insight thereby in how informed consent is applied in the daily practice of clinical trials. Interviews were held with 198 adult patients and 32 trial-clinicians. Instead of focusing on patient comprehension of the information disclosed we analyzed patient perceptions of informed consent. Patients proved to be quite satisfied with the oral and written information disclosure. Patients' perceptions of the manner and content of information disclosure are influenced by more general attitudes towards medical care, research and institutions. Patients' trust in medical experiments, belief in the integrity of physicians and interest in medical affairs have an impact on the way patients perceive information disclosure. To improve the quality of the informed consent procedure, we propose a patient motivation classification (PMC) to enable trial-clinicians to gain more insight into patient motivation. Relevant factors found in our data have been used as criteria for classification. An informed decision making checklist (IDC) is suggested for patients as a general outline for patient education, covering relevant socio-psychological factors of enrollment.

Attitude to Health↗
PubMed1996

Glycoprotein D-negative pseudorabies virus can spread transneuronally via direct neuron-to-neuron transmission in its natural host, the pig, but not after additional inactivation of gE or gI.

Envelope glycoprotein D (gD) is essential for entry of pseudorabies virus (PRV) into cells but is not required for the subsequent steps in virus replication. Phenotypically complemented gD mutants can infect cells and can spread, both in vitro and in mice, by direct cell-to-cell transmission. Progeny virions released by infected cells are noninfectious because they lack gD. The aim of this study was to determine the role of gD in the neuropathogenicity of PRV in its natural host, the pig. We investigated whether gD-negative PRV can spread transneuronally via synaptically linked neurons of the olfactory and trigeminal routes. High doses of a phenotypically complemented gD mutant and gD mutants that are unable to express either gI or gI plus gE were inoculated intranasally in 3- to 5-week-old pigs. Compared with the wild-type virus, the virulence of the gD mutant was reduced. However, pigs inoculated with the gD mutant still developed fever and respiratory signs. Additional inactivation of either gI or gI plus gE further decreased virulence for pigs. Immunohistochemical examination of infected pigs showed that a PRV gD mutant could replicate and spread transneuronally into the central nervous system (CNS). Compared with the wild-type virus, the gD mutant had infected fewer neurons of the CNS on day 2. Nevertheless, on day 3, the gD-negative PRV had infected more neurons and viral antigens were present in second- and third-order neurons in the olfactory bulb, brain stem, and medulla oblongata. In contrast, gD mutants which are unable to express either gI or gI plus gE infected a limited number of first-order neurons in the olfactory epithelium and in the trigeminal ganglion and did not spread transneuronally or infect the CNS. Thus, transsynaptic spread of PRV in pigs can occur independently of gD. Possible mechanisms of transsynaptic transport of PRV are discussed.

Animals↗
PubMed1996

Planned development and evaluation of AIDS/STD education for secondary school students in The Netherlands: short-term effects.

This study evaluated the effects of an AIDS/STD curriculum for 9th- and 10th-grade students in the Netherlands. Curriculum development was based on (1) theory-based need assessments among students and teachers, (2) pilot testing of data-based and theory-based methods and materials, and (3) cooperation between researchers and students, teachers, and gatekeepers within the school system. Using a quasi-experimental design, program effects on students' attitudes, beliefs, and sexual behavior were compared with those of current AIDS/STD education practice. The results indicated that the experimental curriculum had a stronger favorable impact on students' attitudes and beliefs regarding using condoms consistently. Regarding sexual risk behavior, a differential curriculum effect could be demonstrated. These findings support the contention that current AIDS/STD education can be improved by (1) using empirical data, (2) applying multiple theories from the social sciences, and (3) involving representatives within the school system in the development process.

Acquired Immunodeficiency Syndrome↗
PubMed1996

HIV seropositive gay men: understanding adoption of safe sexual practices.

The aim of this study was to determine the best predictors of safe sex practices among HIV seropositive gay men. A group of 96 homosexual men living with HIV completed a questionnaire that investigated theoretical constructs of the Ajzen's (1988) theory of planned behavior with respect to condom use for anal intercourse and sexual practices without anal intercourse. Other variables such as Triandis's (1977) construct of personal normative belief, psychological distress, and alcohol and drug use before sexual encounters were also investigated. Results indicated that the best predictor of intention to use condoms was perceived behavioral control. Personal normative belief was another important predictor of this intention. Although the best predictor of intention to have only sex without anal intercourse was perceived subjective norm, this intention was also significantly explained by perceived behavioral control. Moreover, perceived behavioral control was a significant predictor of having only sex without anal intercourse. Public health interventions among HIV seropositive gay men should aim mainly at increasing perception of behavioral control.

Adult↗
PubMed1995

Barriers to wearing bicycle safety helmets in The Netherlands.

OBJECTIVE: To explore behavioral factors that determine whether children (aged 7 to 13 years) wear bicycle safety helmets. DESIGN: Cross-sectional survey. SETTING: Three Dutch primary schools in Breda, Maastricht, and Terneuzen, the Netherlands. PARTICIPANTS: Two hundred fifty-nine children aged 7 to 13 years. INTERVENTION: Wearing a bicycle safety helmet for 6 consecutive weeks. RESULTS: Information about experiences with the bicycle safety helmet was gathered via questionnaires. Wearing a bicycle safety helmet was described as inconvenient, time-consuming, and uncomfortable. Children also perceived negative reactions from their social environment. CONCLUSIONS: Planned health promotion activities will be essential for the introduction of bicycle safety helmets to be successful. These activities should focus particularly on developing a comfortable bicycle safety helmet, creating facilities to store bicycle safety helmets, and changing negative social norms regarding wearing a bicycle safety helmet.

Adolescent↗
PubMed1995

Behavioral determinants of mothers' safety measures to prevent injuries of pre-school children.

Home-related injuries are a major threat to pre-school children in the western world. In this study the behavioral determinants of 18 parental safety measures were assessed. To select behavioral determinants, the Attitude-Social influence-Self-efficacy/barriers model was used with the inclusion of variables from the Health Belief Model and the Protection Motivation Theory. A written questionnaire was completed by 1129 Dutch mothers of pre-school children. Most safety measures were explained (rather) well by the same set of determinants. Main determinants for adopting or not adopting a safety measure were the mother's belief in the necessity of the safety measure according to the child's age, her belief about her partner's opinion on the necessity and her belief about the success of taking the measure. Subsequent important determinants were the mother's belief about the inconvenience and instrumentality of the safety measure; the perceived susceptibility had a minor or moderate influence on most measures. This study did not indicate that more highly educated mothers were more knowledgeable about safety-related subjects. The theoretical implications of this study are discussed.

Accidents, Home↗
PubMed1995

Diffusion of AIDS curricula among Dutch secondary school teachers.

This study reports data from a sample of 698 Dutch secondary school teachers intending to provide classroom AIDS education. The study addresses determinants of awareness knowledge about and adoption of four nationally disseminated AIDS curricula. The results indicated that knowledge acquisition was largely dependent on diffusion networks within schools. Transition from awareness knowledge to adoption appeared to be mediated by perceived instrumentality, subjective norms, perceived colleague behavior, and teachers' sexual morality. Preferences for using one curriculum rather than another were related to the same variables, although financial costs became slightly more important. It is concluded that effective dissemination strategies should combine (1) development of validated materials with clear instruction for implementation, (2) focused mass media communication, (3) close collaboration of curriculum designers, linking agents, and teachers, and (4) access to in-person assistance.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Determinants of safe and risk-taking sexual behavior among gay men: a review.

Since the outbreak of the AIDS epidemic, gay men have made impressive changes in their sexual behavior. Notwithstanding these changes, there are several studies that show considerable within-subject variability in risk categories, indicating that for a substantial number of gay men it is difficult to be consistently safe. A large number of studies have examined the relationship between sexual behavior and determinants of that behavior. This review reports and discusses the findings with regard to demographic, situational, behavioral, and psychosocial determinants.

HIV Infections↗