Hilde Tobi

Wageningen University, Wageningen, Gelderland, Netherlands

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Publications (64)162.27 Total impact

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    ABSTRACT: City rankings that aim to measure the environmental sustainability of European cities may contribute to the evaluation and development of environmental policy of European cities. The objective of this study is to identify and evaluate the methodological characteristics of these city rankings. First, a methodology was developed to systematically identify methodological characteristics of city rankings within different steps of the ranking development process. Second, six city rankings European Energy Award, European Green Capital Award, European Green City Index, European Soot-free City Ranking, RES Champions League, Urban Ecosystem Europe were examined. Official websites and any methodological documents found on those websites were content analyzed using the developed methodology. Interviews with representatives of the city rankings were conducted to acquire any additional information. Results showed that the city rankings varied greatly with respect to their methodological characteristics and that all city rankings had methodological weaknesses. Developers of city rankings are advised to use the methodology developed in this study to find methodological weaknesses and improve their ranking. In addition, developers ought to be more transparent about the methodological characteristics of their city rankings. End-users of city rankings are advised to use the developed methodology to identify and evaluate the methodological characteristics of city rankings before deciding to act on ranking results.
    Ecological Indicators 01/2014; 43:132–142. · 2.89 Impact Factor
  • Hilde Tobi
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    ABSTRACT: An area of application of measurement with increasing relevance to science and society is interdisciplinary research. Measurement in interdisciplinary research poses new challenges to the theory of measurement, especially when scientists with different disciplinary cultures collaborate. A common framework that allows and invites communication about the process of measurement, including the content and form of the entities under study, is needed. The present paper aims to contribute to such a framework by operational widely-defined measurement and how the portfolio representation of measurement fits within operational widely-defined measurement and supports measurement of the kind of complex attributes often investigated in interdisciplinary research.
    Measurement. 01/2014; 48:228–231.
  • Hilde Tobi, Jarl K. Kampen
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    ABSTRACT: Likert-type of questions are prone to differences in response styles. The aim of the present study is to examine possible cross-cultural differences regarding scale effects resulting from different answer categories. This study aims to extend the literature on scale effects to a foreign language. An English questionnaire containing two experimental questions was presented to students enrolled in international MSc programs. In addition to the experimental questions, the questionnaire contained filler questions, demographic questions, and questions on English proficiency. The questionnaires differed only from each other with respect to answer categories and scale presented with the experimental questions. The questionnaire was presented during class, to 526 students coming from over 70 different countries. These countries were classified according to continent and language into 10 groups of which nine were large enough to be included in the analysis. After considering possible confounding factors, like age, gender, English language proficiency, and disciplinary background, scale effects were shown to be present across groups of countries. These differences seriously affect rankings. Concludingly, scale effects persist in non-native language questionnaires, and the effect sizes differ across cultures.
    Quality and Quantity 01/2013; · 0.73 Impact Factor
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    ABSTRACT: The purpose of this paper is to provide empirical evidence on how various user groups related to Marine Protected Areas (MPAs) interpret desirable data attributes, whether their interpretations differ and to what extent. Moreover, this study aims to make a methodological contribution to the interpretive information systems (IS) literature by showing the potential of Spradley’s (1979) ethnographic methods for understanding the human context in IS research and practice. Semi-structured interviews of MPA managers, academics, government officials, and environmentalists were analysed in four steps. Our findings show that each of the five data attributes studied encompassed more than one and often partly overlapping meanings. Commonalities and differences in interpretations between groups were observed. Users’ organisational background helped to explain these differences; cross-cutting themes that seemed to guide users’ interpretations and actions were perceived legitimacy and accountability of practices along the data value chain. Systematic use of ethnographically-informed methods allowed the detection of subtle differences in how users constructed meaning. As these different interpretations may lead to misunderstandings during requirements engineering, Spradley’s approach could prove useful as a tool not only to elicit and analyse requirements, but also to facilitate unambiguous communication to reach mutual understanding among participants. This may help to improve IS development and thus enhance IS use for participatory governance and management in MPAs.
    Environmental Modelling and Software 01/2013; 41:185-198. · 3.48 Impact Factor
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    ABSTRACT: Day care at green care farms (GCFs) is a new care modality for community-dwelling older people with dementia. In view of the more physical and normal daily life activities available at GCFs than at RDCFs, we investigated whether functional decline differed between subjects from both day care settings. In this observational cohort study, primary caregivers of 47 subjects from GCFs and 41 subjects from RDCFs rated the subjects’ functional performance three times during one year. They also provided information on the subjects’ diseases and medication use. Generally, no significant change over time in functional performance, the number of diseases and the number of medications was observed, and no differences in these rates of change were found between subjects from both day care settings. This study suggests that GCFs are not more effective in maintaining functional performance or slowing down its decline in community-dwelling older people with dementia than RDCFs.
    Dementia 01/2012; 11(4):503-519.
  • J. K. Kampen, H. Tobi
    Journal of Applied Ecology - J APPL ECOL. 01/2012;
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    ABSTRACT: The study was undertaken in the Ejura-Sekyedumasi District of Ghana to investigate how household headship characteristics and labour availability relate with the household’s decision to keep and spend time on small ruminants. Key informants were interviewed prior to a census of all the 407 households in two villages, to collect demographic, crop, and livestock data, which was used in bivariate and logistic regression analyses. A subsequent time use study involved a stratified sample of 24 households, and the t- test was used to compare households. In general, female-headed households (FHH) were of lower socio-economic status, and had fewer adult household members and less livestock, compared to male-headed households (MHH). The final logistic regression model had a 77.1% success rate in predicting households keeping small ruminants, with socio-economic status and sex of the household head, presence of poultry and the number of active adults as significant predictors. Characteristics of FHH that kept small ruminants were not significantly different from their male counterparts, but the former spent less time feeding their animals. The odds of keeping small ruminants were ultimately 2.1 times higher for male-headed households. The low socio-economic status of most FHH with less labour availability is a disincentive for small ruminant rearing
    Livestock Research for Rural Development 23 (2011) 1. 01/2011;
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    ABSTRACT: With the ongoing demographic shift, the quality of life and health promotion among older individuals are becoming increasingly important. Recent research suggests that Sense of Coherence positively affects quality of life. Hence, a valid and reliable measurement of Sense of Coherence is pivotal. The 13-item Orientation to Life Questionnaire (OLQ-13) can be used to measure Sense of Coherence. The purpose of the present study is to assess the psychometric properties, validity, and reliability, of the OLQ-13 in community-dwelling individuals, aged 65 and older. The OLQ-13 scale was administered as part of a healthy aging project for non-institutionalized people aged 65 years and older. Internal consistency and reliability were assessed by means of inter-item and test-halves correlations and Cronbach's alpha. Construct validity was explored using cluster analysis and exploratory factor analysis (n = 703) and tested using confirmatory factor analysis on a separate subset of individuals (n = 658). Item face validity was investigated by means of 12 semi-structured interviews. The reliability and the validity of the OLQ-13 in this population of non-institutionalized individuals aged 65 years and older was ambiguous, at least partly due to the poor performance of two items (b and d), which was confirmed by results from the qualitative part of this study. The psychometric properties of the proposed OLQ-11, obtained by deleting the two items, were better. In particular, the interpretation of exploratory factor solution improved. Whereas the underlying theoretical constructs could not be linked to the exploratory analyses of OLQ-13, this was to some extent possible in OLQ-11. The superior validity of OLQ-11 over OLQ-13 was supported by the better model fit in the confirmatory factor analysis. The present mixed-method study suggests the proposed OLQ-11 as a more suitable instrument for measuring Sense of Coherence than the OLQ-13 in a population of ageing individuals. This study confirms that the validity and reliability of OLQ-13 may differ substantially in different populations.
    Health and Quality of Life Outcomes 01/2011; 9:37. · 2.27 Impact Factor
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    ABSTRACT: This study aimed to compare dietary intake of older people with dementia receiving day care at regular day care facilities (RDCFs) or at so-called green care farms (GCFs). A comparative cross-sectional study was performed at 10 GCFs and 10 RDCFs in the Netherlands. 30 subjects from GCFs and 23 subjects from RDCFs, aged 65 years or over, were included in the study. Subjects from GCFs were mostly married males who were aged younger than the subjects from RDCFs who were mostly widowed females. Dietary intake of the subjects was observed and/or recorded both at home and during their time at the day care facility. In the GCF group, average total energy intake was significantly higher than in the RDCF group (8.8 MJ/d vs. 7.2 MJ/d). Also total carbohydrates and protein intakes were higher in the GCF group than in the RDCF group (with 257 g/d vs. 204 g/d, and 76 g/d vs. 65 g/d respectively). In addition, average total fluid intake was significantly higher in the GCF group than in the RDCF group (2577 g/d vs. 1973 g/d). Multiple linear regression analyses revealed that after taking possible confounders into account, day care type was still significantly related to the intake of energy, carbohydrates and fluids. This study suggests beneficial effects of this new type of day care on dietary intake by community-dwelling older people with dementia.
    The Journal of Nutrition Health and Aging 05/2010; 14(5):352-7. · 2.39 Impact Factor
  • H. Tobi, L. J. Kalverdijk
    Journal of Clinical Microbiology - J CLIN MICROBIOL. 01/2010; 7(4).
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    ABSTRACT: This study aimed at investigating the use of psychosocial interventions and psychotropic co-medication among stimulant-treated children with attention-deficit hyperactivity disorder (ADHD) in relation to the presence of psychiatric co-morbidity. Stimulant users younger than 16 years were identified in 115 pharmacies and a questionnaire was sent to their stimulant prescribing physician. Of 773 questionnaires sent out, 556 were returned and were suitable for analysis (72%). The results are based on 510 questionnaires concerning stimulant-treated children for whom a diagnosis of ADHD was reported. Of the 510 children diagnosed with ADHD, 31% had also received one or more other psychiatric diagnoses, mainly pervasive developmental disorder or oppositional defiant disorder/conduct disorder. We found an association between the presence of co-morbidity and the use of psychosocial interventions for the child (P < 0.001) and the parents (P < 0.001). In the ADHD-only group, 26% did not receive any form of additional interventions, while psychosocial interventions varied from 8 to 18% in children with ADHD and psychiatric co-morbidity. The presence of diagnostic co-morbidity was also associated with the use of psychotropic co-medication (overall, P = 0.012) and antipsychotics (P < 0.001). Stimulant-treated youths with ADHD and psychiatric co-morbidity received more psychosocial interventions and psychotropic co-medication than children with ADHD-only. The type of psychosocial interventions and psychotropic co-medication received by the children and their parents, depended on the specific co-morbid psychiatric disorder being present.
    European Child & Adolescent Psychiatry 11/2009; 19(2):159-66. · 3.70 Impact Factor
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    ABSTRACT: New drugs and new formulations enter the growing market for ADHD medication. The growing awareness of possible persistence of ADHD impairment beyond childhood and adolescence resulting in increased pharmacotherapy of ADHD in adults, is also a good reason for making an inventory of the what is generally known about pharmacotherapy in ADHD. To discuss current issues in the possible pharmacotherapy treatment of ADHD in children, adolescents and adults with respect to the position of pharmacotherapy in ADHD treatment guidelines, the pharmacoepidemiological trends, and current concerns about the drugs used. A search of the literature with an emphasis on the position of pharmacotherapy in ADHD treatment guidelines, the pharmacoepidemiological trends, and current concerns about the drugs used in pharmacotherapy. According to the guidelines, the treatment of ADHD in children consists of psychosocial interventions in combination with pharmacotherapy when needed. Stimulants are the first-choice drugs in the pharmacological treatment of ADHD in children despite a number of well known and frequently reported side effects like sleep disorders and loss of appetite. With regard to the treatment of adults, stimulant treatment was recommended as the first-choice pharmacotherapy in the single guideline available. Both in children and adults, there appears to be an additional though limited role for the nonadrenergic drug atomoxetine. The increase of ADHD medication use, in children, adolescents and in adults, can not only be interpreted as a sign of overdiagnosis of ADHD. Despite the frequent use of stimulants, there is still a lack of clarity on the effects of long-term use on growth and nutritional status of children. Cardiovascular effects of both stimulants and atomoxetine are rare but can be severe. The literature suggests that atomoxetine may be associated with suicidal ideation in children. Although pharmacotherapy is increasing common in the treatment of ADHD in both children and adults, there are still a lot of questions about side effects and how best to counter them. This suggests an important role for close monitoring of children and adults treated with stimulants or atomoxetine.
    International Journal of Clinical Pharmacy 07/2009; 31(5):509-16. · 0.92 Impact Factor
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    ABSTRACT: The authors examined prevalence, incidence, and duration of antipsychotic drug use in the northern and eastern regions of the Netherlands between 1997 and 2005 among youths in regard to age, gender, and class of drug. Prescription drug dispensing data were collected from community pharmacies in the northern Netherlands (www.iadb.nl). Prevalence, incidence, and duration of use were studied among roughly 100,000 youths ranging in age from infancy to age 19 years, calculated by age group (zero to four years, five to nine years, ten to 14 years, and 15 to 19 years), for boys and girls, and for first- and second-generation antipsychotics. Duration of use was compared between youths who started antipsychotic treatment in 1998-1999 and those who started in 2001-2002. From 1997 to 2005, prevalence increased from 3.0 to 6.8 per thousand. Prevalence was highest among ten-year-olds to 14-year-olds (11 per thousand), especially among boys (17 per thousand). The increased prevalence was mainly attributable to an increased use of second-generation antipsychotics and to a longer duration of use. Median duration of use doubled from .8 year in 1998-1999 to 1.6 years in 2001-2002. Second-generation antipsychotic drugs were increasingly prescribed, and for longer periods of time, to younger children, probably because of new indications. This practice increases the exposure of a young population to (partly unknown) risks.
    Psychiatric Services 06/2008; 59(5):554-60. · 2.01 Impact Factor
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    ABSTRACT: Attention-deficit hyperactivity disorder (ADHD) is the most common mental health disorder in youths. Stimulants are the drugs of first choice in the treatment of ADHD. It has been suggested that full costs associated with the treatment of ADHD may be reduced by once-daily administration regimens of stimulants. To estimate the cost effectiveness of treatment with long-acting methylphenidate osmotic release oral system (OROS) [Concerta] for youths with ADHD for whom treatment with immediate-release (IR) methylphenidate is suboptimal. We developed a Markov model to obtain an incremental cost-effectiveness ratio (ICER). The analysis covered 10 years, with a Markov cycle of 1 day. Costs (in 2005 euros ) included medication, consultations and treatment interventions, and additional costs for attending special education. Quality-adjusted life-years (QALYs) were used as the effectiveness measure. Outcome probabilities were taken from the medical literature and an expert panel of five child psychiatrists and paediatricians. Univariate sensitivity analyses were performed to assess the robustness of the base-case estimate. Multivariate sensitivity analysis was used to estimate a worst- and best-case ICER. The ICER of methylphenidate-OROS treatment in youths with ADHD for whom treatment with IR methylphenidate is suboptimal was euro 2004 per QALY. Total costs after 10 years were euro 15,739 for the IR methylphenidate pathway and euro 16,015 for the methylphenidate-OROS pathway. In the univariate sensitivity analysis, the ICER was sensitive to changes in resource use and the probability of stopping stimulant treatment in favour of IR methylphenidate. An ICER of 0 was reached with a 6.2% price reduction of methylphenidate-OROS. Methylphenidate-OROS is a cost-effective treatment for youths with ADHD for whom treatment with IR methylphenidate is suboptimal. Higher medication costs of methylphenidate-OROS were compensated for by savings on resource use, yielding similar 10-year costs compared with treatment with IR methylphenidate. Our analysis is sensitive to both clinical parameters and (differences in) resource utilization and costs between the groups modelled, warranting further research within clinical trials and observational databases, and into the full scope of costs.
    CNS Drugs 02/2008; 22(2):157-70. · 4.83 Impact Factor
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    ABSTRACT: To show the necessity of distinguishing several patterns of drug prescribing that may lead to co-medication. It is demonstrated how these different patterns can be investigated using large databases containing pharmacy data or reimbursement data. Two examples illustrate how the particular pattern of co-medication studied will influence the reported proportion of patients having co-medication, the use of antidepressants among people using anticonvulsants, and the use of antihistamines among people receiving penicillines. Depending on definition and period considered, the percentage of anticonvulsant users co-medicated with antidepressants ranged from 5.8% (95%CI 5.0%, 6.8%) to 14.5% (95%CI 13.2%, 15.9%) in 2000. Comparing 2002 with 2000, the ratio of proportions ranged from 1.3 to 2.1. The percentage of people who received penicillines and were co-medicated with antihistamines ranged from 0.5% (95%CI 0.4%, 0.6%) to 9.7% (95%CI 9.3%, 10.2%) in 2000. Comparing 2002 with 2000, the ratio of proportions ranged from 1.2 to 1.6. The co-medication patterns investigated yielded clinical as well as statistically significant different estimates. The estimates differed up to a factor 2.5 for the drugs usually prescribed for long periods, and a factor 12 for drugs prescribed for short periods. Hence, we propose to distinguish the patterns 'co-prescribing', 'concomitant medication,' and 'possibly concurrent medication.' The research question determines the co-medication pattern of interest, and the drug and disease under study determine the time window.
    Pharmacoepidemiology and Drug Safety 05/2007; 16(4):405-11. · 2.90 Impact Factor
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    ABSTRACT: This study investigated the interrelationship between psychopharmacotherapy in general and the use of specific psychotropic drugs and pervasive developmental disorder and other behavior problems in children and adolescents with mental retardation. A total of 862 participants 4 to 18 years of age, including all levels of mental retardation, were recruited through facilities for children with mental retardation in Friesland, The Netherlands. Information on medication was collected through parent interviews. Behavior problems were investigated with a standardized parent questionnaire (Developmental Behavior Checklist). A pervasive developmental disorder classification was based on the Pervasive Developmental Disorder in Mental Retardation Scale, completed by psychologists or teachers. Logistic regression analysis was used to investigate the relationship between the use of psychotropic drugs and pervasive developmental disorder and other behavioral problems, in the presence of possible confounders. One of 10 participants used psychotropic medication. The main factors associated with psychotropic drug use were pervasive developmental disorder and disruptive behavior. The level of functioning was also associated. Self-absorbed behavior was statistically significantly associated with clonidine use and disruptive behavior with stimulant use. Pervasive developmental disorder and communication problems were the main factors associated with the use of antipsychotic drugs. Age also played a role, whereas gender, living situation, and level of mental retardation did not. Antipsychotic drugs were associated with pervasive developmental disorder, whereas clonidine and stimulants were associated with self-absorbed and disruptive behavior, respectively. Although clonidine and risperidone are not registered for the problems reported and the other nonstimulants were only sometimes used on-label, their use was associated with specific psychiatric or behavioral problems.
    PEDIATRICS 01/2007; 118(6):e1860-6. · 4.47 Impact Factor
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    ABSTRACT: An N-of-1 trial is a double-blind placebo-controlled randomized trial to objectively and systematically evaluate the individual's response. This approach seems extraordinarily suitable for assessing the efficacy of stimulants in the treatment of attention deficit hyperactivity disorder (ADHD). The aim is to examine the use of N-of-1 trials among youths in the Netherlands, the protocols used, and the continuation of stimulant treatment thereafter. Physicians requesting N-of-1 trials with stimulants were interviewed about their rationale and protocol. Prevalence and continuation were investigated by extracting N-of-1 trials among youths <20 years of age from a large pharmacy dispensing database for 2000-2004. The main purpose of N-of-1 trials mentioned by physicians was the assessing of individuals' response and dose-finding. Trial length, dosing schedule and efficacy assessment differed per physician. Trials consisted of a maximum of two treatment periods per dose. The annual percentage of youths starting stimulant treatment with an N-of-1 trial fluctuated between 0.6% (3/462) and 3.3% (10/301). No statistical significant difference could be detected between the continuation of stimulant treatment with or without an N-of-1 trial (p = 0.71). N-of-1 trials with stimulants are infrequently and not optimally used in the Netherlands. The results of N-of-1 protocols described by physicians are of questionable value, due to the small number of treatment periods per dose. More uniformity in the protocols would make it easier to encompass the N-of-1 methodology in physicians' daily practice.
    European Journal of Clinical Pharmacology 01/2007; 63(1):57-63. · 2.74 Impact Factor
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    ABSTRACT: To compare antidepressant prevalence data in youths across three western European countries (Denmark, Germany, and the Netherlands) with US regional data in terms of age and gender and to show proportional subclass antidepressant (ATD) use. A population-based analysis of administrative claims data for the year 2000 was undertaken in 0 to 19-year-old enrollees who were part of the insured populations from four countries having a total of from 72,570 to 480,680 members. ATD medication utilization in the US dataset (1.63%) exceeded that of three Western European countries (prevalence ranged from 0.11 to 0.54%) by at least 3-fold. There were major variations in the use of subclasses: tricyclic antidepressants (TCAs) predominated in Germany while selective serotonin reuptake inhibitors (SSRIs) predominated in the US, Denmark and the Netherlands. Cross-national variations should be further explored to understand the factors related to these differences and how prevalence differences relate to effectiveness and safety. Community-based cohorts should be followed to establish outcomes in the usual practice setting.
    Pharmacoepidemiology and Drug Safety 12/2006; 15(11):793-8. · 2.90 Impact Factor
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    ABSTRACT: To investigate the dosage and duration of inhaled steroids prescribed to children and to compare the prescribed doses with recommended doses for the treatment of asthma in children. For 2514 Dutch children aged 0-12 years who had used inhaled steroids in 2002, pharmacy dispensing data were obtained from the InterAction database, type of steroid (beclomethason, budesonide, fluticasone) and type of user (first time or existing) and the average prescribed doses according to age were determined and compared with the doses as recommended in the national Dutch Nederlands Huisartsen Genootschap (NHG) guideline. Furthermore, for all first-time users the duration of therapy with inhaled steroids was determined using a Kaplan-Meier analysis. The major findings were that: (i) overall 43% of children starting inhaled steroids were prescribed doses that are half the recommended dose or less; (ii) overall 8% of the children starting inhaled steroids were prescribed doses that were twice the recommended dose or more, up to 50% in the 12-year-olds fluticasone group; and (iii) only 8% of the children who started with inhaled steroids used them continuously for a full year. Doses of inhaled steroids for many children deviate from those recommended, with lower doses more frequently occurring than higher doses. Less than 10% of the children receive prescriptions for a prolonged period of time.
    British Journal of Clinical Pharmacology 11/2006; 62(4):383-90. · 3.58 Impact Factor
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    ABSTRACT: The aim of this study was to describe current practices around initiation and follow-up care of stimulant treatment among stimulant-treated children in a nationwide survey among parents. A total of 115 pharmacies detected current stimulant users <16 years old in their pharmacy information system and sent parents a questionnaire regarding their child's stimulant treatment. Parents returned 924 of 1,307 questionnaires (71%). The median age of the stimulant users was 10 years and 85% were boys. In all, 91% were diagnosed with attention-deficit/hyperactivity disorder (ADHD). In 77% of the cases, the child or parents received other therapies besides stimulants-21% received psychotropic co-medication, with melatonin (11%) and antipsychotics (7%) being mentioned most frequently. Stimulant use was primarily initiated by child psychiatrists (51%) and pediatricians (32%), but most children received repeat prescriptions from general practitioners (61%). Of these 924 children, 19% did not receive any follow-up care, and transfer of prescribing responsibility increased the risk of not receiving follow-up care. The 732 children (79%) who were monitored visited a physician approximately twice a year. During follow-up visits, pediatricians performed physical check ups significantly more often. Stimulant treatment in The Netherlands is initiated mainly by specialists such as child psychiatrists and pediatricians. In the current study, follow-up care for stimulant-treated children in The Netherlands appeared to be poor, suggesting an urgent need for improvement.
    Journal of Child and Adolescent Psychopharmacology 09/2006; 16(4):432-40. · 2.77 Impact Factor

Publication Stats

725 Citations
162.27 Total Impact Points

Institutions

  • 2009–2014
    • Wageningen University
      • Research Methodology Group
      Wageningen, Gelderland, Netherlands
    • Pharmo Institute for Drug Outcomes Research
      Utrecht, Utrecht, Netherlands
  • 1999–2008
    • University of Groningen
      • • Department of Psychiatry
      • • PharmacoEpidemiology and PharmacoEconomics (PE²) Unit
      Groningen, Province of Groningen, Netherlands
  • 2006
    • Medisch Centrum Leeuwarden
      Leewarden, Friesland, Netherlands