Biomedical subjects

H De Vries

Publications and source records attributed to H De Vries.

At least 19 recordsLinked to original sources

PubMed2006

Identifying determinants of protocol adoption by midwives: a comprehensive approach.

Adoption of potentially effective preventive interventions often fails. This study aimed to identify factors that determine why midwifery practices decide to use a smoking cessation protocol, using a comprehensive model of both organizational and psychosocial factors. A cross-sectional survey was conducted among representatives of all 446 Dutch midwifery practices, of whom 251 (56%) responded. The results show that adoption of the protocol was facilitated by the presence of practice assistants and impeded by a large proportion of clients of foreign ethnic origin. The most successful information channel was the midwives' professional association. A consistent positive attitude (perceiving a lot of advantages, few disadvantages and a low level of ambivalence) and positive social norms toward using the protocol, a perceived large proportion of midwives who use the protocol and knowledge about the protocol significantly increased the likelihood of adoption. The decision to use the protocol was better explained by personal awareness and motivation factors than by organizational factors.

Adult↗

PubMed2006

Gas cooking, kitchen ventilation, and asthma, allergic symptoms and sensitization in young children--the PIAMA study.

BACKGROUND: Several studies reported inconsistent associations between using gas for cooking and respiratory symptoms or lung function in children. Kitchen ventilation characteristics may modify the relationship between gas cooking and respiratory health. The aim of this study was to investigate the effect of kitchen ventilation (while cooking) on the relationship between gas cooking, combustion product dispersal, and respiratory and allergic outcomes in children. METHODS: Data on respiratory and allergic symptoms and diagnoses were collected by yearly questionnaires in a population of over 3000 children participating in a birth cohort study on development of allergy and asthma. At 4 years of age, a sub-sample of 647 children provided blood samples for antibody testing. Data on gas cooking and kitchen ventilation were collected when the children were 5 years old. Based on these data a model was constructed to determine the chance of accumulation of combustion products (CACP) in the kitchen. RESULTS: No relationship was found between gas cooking and any of the respiratory or allergy outcomes except nasal symptoms. The overall results did not change when the 'CACP' was used as exposure variable instead, while the association for nasal symptoms decreased to borderline significance. CONCLUSION: Our results suggest that gas cooking per se is associated with nasal symptoms in young children and not with the other respiratory symptoms that were investigated. Taking kitchen ventilation characteristics into account did not lead to different conclusions in this population where, according to the classification system, the majority of households using gas for cooking have insufficient kitchen ventilation.

Air Pollution, Indoor↗

PubMed2005

General public's knowledge, interest and information needs related to genetic cancer: an exploratory study.

Single-group interviews were conducted with 49 people to get an idea of what and how the general public thinks about genetic cancer. Understanding what people think and need is crucial for adequate public health communication about genetic issues. Group discussions revealed that people believed that the vulnerability for cancer was largely dependent on their lifestyle, and that they were at risk if cancer ran in their family. Participants found it difficult to distinguish cancer from genetic cancer since in both cases the cause was related to cell problems. People felt that they lacked adequate knowledge of genetic cancer, which was also confirmed by the misconceptions revealed during the discussions. Participants mentioned both advantages (knowing one's risk, performing preventive actions, more openness, less taboo, and more knowledge) and disadvantages (fear arousal, difficult to time, undirected, tenability) of receiving genetic information. Although people felt ambivalent about wanting to receive genetic cancer information, as yet the general tendency seemed to be to postpone opening up to such information until there was a relevant case in the family. Subsequently, preferred information sources were family members and health professionals. According to the participants mass media should provide information on relevant features of genetic cancer to look out for. As yet, people showed little interest in biological genetic information.

Adult↗

PubMed2004

Model of unplanned smoking initiation of children and adolescents: an integrated stage model of smoking behavior.

BACKGROUND: Two lines of psychological research have attempted to spell out the stages of adolescent smoking initiation. The first has focused on behavioral stages of smoking initiation, while the second line emphasized motivational stages. METHODS: A large international sample of European adolescents (N = 10,170, mean age = 13.3 years) was followed longitudinally. Self-reported motivational and behavioral stages of smoking initiation were integrated, leading to the development of the Model of Unplanned Smoking Initiation of Children and Adolescents (MUSICA). The MUSICA postulates that youngsters experiment with smoking while they are in an unmotivated state as regards their plans for smoking regularly in the future. RESULTS: More than 95% of the total population resided in one of the seven stages distinguished by MUSICA. The probability of starting to smoke regularly during the 12 months follow-up period increased with advanced stage assignment at baseline. Unique social cognitive predictors of stage progression from the various stages were identified, but effect sizes of predictors of transitions were small. CONCLUSIONS: The integration of motivational and behavioral dimensions improves our understanding of the process of smoking initiation. In contrast to current theories of smoking initiation, adolescent uptake of smoking behavior was found to be an unplanned action.

Adolescent↗

PubMed2004

Breast self-examination: longitudinal predictors of intention and subsequent behaviour.

This study analysed in a longitudinal design the relationship between past breast self-examination (BSE) behaviour, determinants, intention and future BSE behaviour in a population of adult Dutch women. Past behaviour and psychosocial determinants were assessed at T1, followed 6 weeks later (T2) with the assessment of the intention to perform BSE monthly. Half a year after the first measurement the current BSE behaviour was assessed by means of a telephone survey (T3) (total end response 78%, n=364). The questionnaires included BSE behaviour, intention, attitude (pros and cons of BSE, anticipated regret, moral obligation), social influence (support, modelling) and self-efficacy. Other background variables assessed were past BSE behaviour, and demographics. Although 81% of the women stated that they performed BSE, only 41% of the women performed BSE correctly. Women who performed BSE correctly differed from women who did not on all psychosocial determinants assessed a half year earlier, with the exception of anticipated regret. Stepwise multiple regression analyses showed that the psychosocial determinants explained 51% of the variance in intention to perform BSE, assessed 6 weeks later; past behaviour accounted for 2% of extra explained variance. Logistic regression analyses showed that past behaviour, the psychosocial determinants and intention were significant predictors of correct BSE behaviour a half year later (Nagelkerke's total explained variance was 47%). It was concluded that misperceptions of correct BSE behaviour was highly prevalent. Both the psychosocial determinants as well as past behaviour were important predictors of intention to perform BSE and subsequent BSE behaviour.

Adult↗

PubMed2002

Sunbed use at home: risk behaviour and psychosocial determinants.

The objective of this study was to analyse the behaviour of people with regard to sunbed use at home, and to analyse the psychosocial determinants of intention and behaviour with regard to limiting the health risk of using sunbeds at home. Data were collected by means of a telephone survey among 349 adults from the Dutch general public who use sunbeds at home (response=95%). Determinants that were assessed were: attitude with respect to safer use and the use of sunbeds in general, the social influences people encounter to use sunbeds in a safer way, and the self-efficacy expectations people have of their ability to use sunbeds more safely. The results showed that there were great differences between people's perceptions of their safe sunbed behaviour, and their actual safety behaviour. Almost all respondents (94%) thought that their sunbed behaviour was safe, while in reality only 37% of the respondents used the sunbed in accordance with the safety guidelines. The safer users of sunbeds differed on many determinants from the unsafe users. Intention to minimize the health risk when using sunbeds could be predicted by a person's perceived self-efficacy, the overall attitude and anticipated regret beliefs (R2=0.52). Sunbed users should be made aware of their risk behaviour with regard to sunbeds as well as providing information on changing determinants, in order to positively change people's intentions and behaviour with regard to the safer use of sunbeds.

Adolescent↗

PubMed2001

Do self-help interventions in health education lead to cognitive changes, and do cognitive changes lead to behavioural change?

OBJECTIVES: The present study examined the extent to which self-help interventions change specific cognitions and the extent to which changes in such cognitions are related to behavioural changes. DESIGN: A randomized field experiment with follow-ups after 2 weeks and 3 months. METHOD: Smokers (N = 1546) were randomly assigned to one of four conditions offering smoking cessation self-help materials containing (1) outcome information, (2) self-efficacy enhancing information, (3) both sorts of information, or (4) no information. RESULTS: First, with regard to behavioural effects, only self-help interventions that included self-efficacy enhancing information were more effective than no information. Second, with regard to the cognitive changes, the data showed that outcome information led to increase in expected positive outcomes but also to increases in self-efficacy expectations. Further, self-efficacy-enhancing information led to increases in self-efficacy. Third, different cognitive changes between T1 and T2 were related to different types of quitting activity at T3 in different groups of smokers. CONCLUSIONS: Some types of information lead to specific cognitive changes, while other types have more generalized cognitive effects. Further, cognitive changes produced by a self-help intervention predict future quitting activity.

Clinical Trial↗

PubMed2000

Subtypes of precontemplating smokers defined by different long-term plans to change their smoking behavior.

Many smokers are not motivated to quit smoking. In the Stages of Change model these smokers are called precontemplators. When developing interventions designed to motivate these smokers to quit, it is of importance to know whether this group is homogeneous or not. In the present study, different groups of precontemplators were distinguished according to their long-term quitting smoking plan: 861 precontemplators were asked to indicate the one plan that best fitted their own plans with regard to their smoking behavior: (1) planning to never quit and not planning to cut down (n = 194), (2) planning to never quit but planning to cut down (n = 186), (3) planning to quit somewhere in the future but not within the next 5 years (n = 290), (4) planning to quit within the next 5 years (n = 136) and (5) planning to quit within the next year but not within the next 6 months (n = 54). These groups of smokers were compared on several variables cross-sectionally and longitudinally. The results indicate that the psychological factors that will have to be targeted in smoking cessation interventions in efforts to motivate smokers to quit could be assessed reliably in precontemplators. Furthermore, precontemplators with different quitting plans differed on several cognitive variables and the quitting plans at pre-test were predictive of quitting activity after 7 months. Precontemplators who received self-help smoking cessation materials made forward changes in quitting plans and these changes seemed to follow a certain order. Forward changes in plans were differentially related to positive outcome expectations, to self-efficacy expectations depending on the quitting plan and not to changes in negative outcomes. The present study is one step in mapping the psychology of low motivation to change behavior.

Adolescent↗

PubMed1999

Targeting smokers with low readiness to change with tailored and nontailored self-help materials.

BACKGROUND: Few smoking cessation self-help materials are available for smokers who are not planning to quit. However, computer-tailored interventions can be designed specifically for these smokers. METHODS: In a large randomized field trial (N = 843), two different tailored smoking cessation self-help interventions (multiple tailoring and single tailoring) and one standardized smoking cessation self-help guide were compared with a no-information control group and with each other. The contents of the tailored interventions were adapted to individuals' self-reported stage of change, outcome expectations, self-efficacy levels, and smoking behavior. RESULTS: The primary outcome measure was forward stage transition. The standardized self-help guide had no effect. Among smokers who were not planning to quit within the next 5 years the multiple-tailored intervention was more effective than the single-tailored intervention. This pattern was supported by the cognitive changes caused by the interventions. Among smokers who were planning to quit within the next 5 years but not within the next 6 months, none of the self-help materials had any effect. CONCLUSION: The present results show that the self-help material currently available in the Netherlands, the standardized self-help guide, was not effective among smokers with low readiness to change. However, computer-generated tailored interventions seem a promising means of communicating information on smoking and smoking cessation to these smokers.

Adult↗

PubMed1999

The development of computer-generated tailored interventions.

Tailoring information to individual characteristics of a person is a promising line of development of self-help interventions. This article presents a three-phase methodology for developing computer-generated tailored interventions. The first phase of the development concerns the formulation of intervention objectives on the basis of analyses of the cognitive determinants of behavior. The second phase concerns the core of the development of a tailored intervention. For each objective, a so-called tailoring matrix is developed which specifies the individual characteristics to which the message will be adapted to. The tailoring matrices are the basis of the tailored messages and the tailoring questionnaire which will assess the individual characteristics. In the third phase, all the separately written messages must be integrated to one coherent intervention text and the lay-out is designed. This methodology may result in largely different tailored interventions depending on the theoretical framework used, the adaptation of the messages and the inclusion of feedback.

Cognition↗

PubMed1999

Computer-tailored nutrition education: differences between two interventions.

The impact of two computer-tailored nutrition education interventions was assessed and compared in a randomized trial among 315 subjects with a pre-test-post-test comparison group design. Respondents in both the experimental and the comparison group received feedback tailored to their consumption of fat, fruit and vegetables. Respondents in the experimental group received additional psychosocial feedback tailored to their attitudes, perceived social support and self-efficacy expectations towards reducing their fat consumption and increasing their consumption of fruit and vegetables. A significant reduction in fat consumption and increase in the consumption of fruit and vegetables were found in both the experimental and the comparison group between pre-test and post-test. Respondents in the experimental group more often indicated that the feedback they received was interesting and easy to understand. Respondents in the comparison group more often reported having reduced their fat consumption because of the feedback they received. No significant differences in consumption of fat, fruit and vegetables were found at post-test between the experimental group and the comparison group. These results do not support the hypothesis that additional psychosocial information is an essential component of effective tailored feedback. The results indicate that tailored feedback might be effective in inducing dietary changes.

Adult↗

PubMed1999

Effectiveness of a social influence approach and boosters to smoking prevention.

This paper presents the short-term and long-term results of a randomized smoking prevention trial. The purpose was to evaluate two smoking prevention programs, a social influence (SI) program and a SI program with an additional decision-making component (SI(DM)). Moreover, the contribution of boosters was assessed as well. Fifty-two schools were randomly assigned to the SI program, the SI(DM) program or a control group. Half of the treatment schools were randomly assigned to the booster condition; the other half did not receive boosters. Both programs consisted of five lessons, each lasting 45 min, and were given in weekly sessions in grades 8 and 9 of high schools in the Netherlands. The most successful program was the SI program with boosters which resulted in a significantly lower increase in smoking rates (5.6 and 9.7%, respectively) compared to the control group (12.6 and 14.9%, respectively) at both 12 and 18 months follow-up. The results suggest that boosters can be an effective tool for maintaining or increasing the effectiveness of smoking prevention programs. It is recommended that the SI program with the booster be implemented at the national level, since this intervention showed the greatest behavioral effects.

Adolescent↗

PubMed1999

The reach and effectiveness of a national mass media-led smoking cessation campaign in The Netherlands.

OBJECTIVES: This study examined the reach, effectiveness, and cost-effectiveness of a mass media-led smoking cessation campaign including television shows, a television clinic, a quit line, local group programs, and a comprehensive publicity campaign. METHODS: A random sample of baseline smokers (n = 1338) was interviewed before and after the campaign and at a 10-month follow-up. A nonpretested control group (n = 508) of baseline smokers was incorporated to control for test effects. RESULTS: Most smokers were aware of the campaign, although active participation rates were low. Dose-response relations between exposure and quitting were found. The follow-up point prevalence abstinence rate attributable to the campaign was estimated to be 4.5% after control for test effects and secular trends. The cost per long-term quitter was about $12. CONCLUSIONS: In spite of a massive rise in tobacco promotion expenditures prior to the campaign and the absence of governmental control over the media, the campaign under study may have increased normal cessation rates substantially.

Community-Institutional Relations↗

PubMed1998

Tailored interventions to communicate stage-matched information to smokers in different motivational stages.

Smokers in stages of low readiness to quit (immotives and precontemplators) and smokers in stages of high readiness to quit (contemplators and preparers) were randomly allocated to 1 of 4 tailored intervention conditions offering outcome information, self-efficacy-enhancing information, both sorts of information, or no information. Data on 1,540 smokers, stratified by stage, were analyzed. The primary outcome measure was stage transition. The hypotheses with regard to stage-matched information for immotives and precontemplators were not verified. With regard to contemplators and preparers, the following was found: Compared with the control group, contemplators benefited the most from both sorts of information, whereas preparers benefited the most from self-efficacy-enhancing information only. Comparisons between contemplators and preparers who were assigned to the matched treatment and contemplators and preparers who were assigned to the mismatched treatment supported these findings.

Adult↗

PubMed1998

Tailoring information to enhance quitting in smokers with low motivation to quit: three basic efficacy questions.

Tailoring information to a target individual's features is a promising line of development in self-help interventions. In this article, 752 smokers with explicit low intention to quit were randomly assigned to 1 of 5 conditions: (a) multiple tailored letters with self-help guide, (b) multiple tailored letters only, (c) a single tailored letter with a self-help guide, (d) a single tailored letter only, or (e) a nontailored intervention. Follow-up assessment took place 4 months after the intervention. Results indicated that the single tailored intervention only had no surplus value compared with a nontailored look-alike intervention. The addition of a self-help guide to a tailored intervention was only useful in highly dependent smokers, and multiple tailoring was more effective than single tailoring. It remains important to elucidate why and for whom certain tailored interventions are more effective.

Adult↗

PubMed1998

Computerized tailored feedback to change cognitive determinants of smoking: a Dutch field experiment.

In the last decade, attempts have been made to improve the efficacy of minimal interventions by tailoring them to individual features. In the development of these tailored interventions, it is important to know which information in interventions is essential. Most smoking cessation interventions contain information on the outcomes of quitting and skills to be used in a quit attempt. The present study was designed to assess the cognitive changes caused by both sorts of information. Therefore, 246 smokers who were planning to quit within 6 months were randomly assigned to three different conditions. In the first condition, the respondents received a computer-generated tailored letter on the outcomes of smoking cessation. In the second condition, the respondents received a computer-generated tailored letter containing self-efficacy enhancing information, mainly on skills. In both conditions, the contents of the letters were based on the pre-test scores of the participants. Participants in the control condition did not receive any cessation information. The results show that information on the outcomes of quitting changed expected outcomes while information on coping skills changed self-efficacy expectations, in comparison with the control condition. Comparing both experimental conditions, information on the outcomes led to changes in expected outcomes, whereas information on coping skills did not lead to higher self-efficacy expectations than information on the outcomes of quitting. It is concluded that the hypothesized effects were partly verified.

Analysis of Variance↗

PubMed1998

Long-term effectiveness of computer-generated tailored feedback in smoking cessation.

Although tailored interventions consisting of only a few pages of information lead to more quitting than no intervention in the short term, the long-term efficacy of a single tailored intervention still has to be proven. In the present study smokers were reactively recruited and randomly allocated to one of four intervention conditions: (1) outcome information, (2) self-efficacy enhancing information, (3) both sorts of information or (4) no information. Smokers in the three experimental groups received computer-generated tailored feedback containing the condition-specific information, by mail. The results from the 14 months follow-up can be summarized as follows. Compared to the no information condition, all three experimental conditions led to significantly more smokers who had engaged in 24-h quit attempts. However, no experimental condition led to more 7-day quitting than the no information condition. With regard to continuous abstinence, the experimental condition offering a combination of outcome information and self-efficacy enhancing information had a significant effect, compared to the no information condition. It is concluded that a minimal six-page tailored intervention can be beneficial in supporting smokers to quit smoking, even after 14 months.

Adult↗

PubMed1998

Measuring support for tobacco control policy in selected areas of six countries.

OBJECTIVE: To explore the validity, reliability, and applicability of using a short, psychometrically sound survey instrument to measure population attitudes toward tobacco control policies. DESIGN: Surveys. SUBJECTS AND SETTING: Student respondents attending university in Australia (n = 403), Hong Kong (n = 336), the Netherlands (n = 351), South Africa (n = 291), the United Kingdom (n = 164) and the United States (n = 241); total n = 1786. MAIN OUTCOME MEASURE: The Smoking Policy Inventory (SPI), a 35-item scale. SPI scores were adjusted for age, income, gender, and smoking status. Estimates of internal consistency and tests of factorial invariance were conducted in each sample. RESULTS: Across all six countries, the SPI was found to be highly reliable and to have a consistent factor structure, indicating that the SPI scale represents a higher order construct that assesses general attitudes about tobacco control policy with five dimensions. In general, the degree of endorsement of anti-tobacco policies as measured by the SPI reflected the extent and strength of tobacco control legislation in those countries. Dutch students were the least likely, and Australian and Hong Kong students the most likely, to support tobacco control policies. CONCLUSIONS: It is possible to develop appropriate and meaningful measurement tools for assessing support of tobacco control policies. Strong evidence was found for internal reliability and structural invariance of the SPI. The SPI may be a useful mechanism for monitoring ongoing policy initiatives, making cross-cultural comparisons, and evaluating population receptiveness to proposed policy approaches.

Adolescent↗