Ruud Houben

Maastricht Universitair Medisch Centrum, Maestricht, Limburg, Netherlands

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Publications (59)244.71 Total impact

  • International journal of radiation oncology, biology, physics 04/2015; 49. DOI:10.1016/j.ijrobp.2015.02.048 · 4.18 Impact Factor
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    ABSTRACT: To realize safe, high-quality treatment, employees should behave according to patient safety standards. Periodic measurement of safety behavior could provide management-relevant information to adjust the implementation of interventions and maximize improvement. Therefore, we constructed a factorial survey measuring safety awareness and intentions for behavior. Cross-sectional results of the factorial survey were compared with results from the Hospital Survey on Patient Safety Culture, distributed in MAASTRO radiotherapy in 2010 to 2011. Respondents were presented 20 scenarios about incidents, randomly varying on work pressure, person causing incident, whether patient level was reached, severity of harm, notification by patient, and management support. After each scenario, questions were asked about safety awareness and behavior. χ and multilevel regression analyses were used. Response rates were 64% (n = 54) for the culture survey and 62% (n = 52) for the factorial survey on intentions. The culture survey reflected positive opinions regarding nonpunitive response and incident reporting, in accordance with high scores (factorial survey) on safety awareness (9.0; scale, 1-10) and reporting intentions (8.7). Whether an incident reached the patient level predicted safety awareness and intentions for safety behavior (β = -1.3/-3.08) most strongly. Severity of harm showed minimal additional effects (β = -0.24/-0.42). The factorial survey presented practical information on safety awareness and intentions for behavior. Therefore, it created additional opportunities for improving safety interventions. Because behavior is expected to change before values, one could hypothesize that factorial surveys would be more sensitive to change than culture surveys. Longitudinal research should further study the surveys' sensitivity to measure changes.
    Journal of Patient Safety 04/2015; DOI:10.1097/PTS.0000000000000192 · 0.88 Impact Factor
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    Annals of Oncology 04/2015; 26(suppl 1):i35-i35. DOI:10.1093/annonc/mdv050.14 · 6.58 Impact Factor
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    ABSTRACT: Objectives: To simultaneously improve patient care processes and clinical research activities by starting a hypothesis-driven reorganisation trajectory mimicking the rigorous methodology of a prospective clinical trial. Methods: The design of this reorganisation trajectory was based on the model of a prospective trial. It consisted of 1) listing problems and analysing their potential causes, 2) defining interventions, 3) defining endpoints and 4) measuring the effect of the interventions (i.e. at baseline and after one and two years). The primary endpoint for patient care was the number of organisational root causes of incidents/ near incidents; for clinical research it was the number of patients in trials. There were several secondary endpoints. We analysed the data using two sample z-tests, chi square, a Mann Whitney U test and the one-way ANOVA with Bonferroni correction. Results: The number of organisational root causes was reduced by 27% (p<0.001). There was no effect on the percentage of patients included in trials. Conclusions: The reorganisational trajectory was successful for the primary endpoint of patient care and had no effect on clinical research. Some confounding events hampered our ability to draw strong conclusions. Nevertheless, the transparency of this approach can give medical professionals more confidence in moving forward with other organisational changes in the same way. Advances in knowledge: This paper is novel because managerial interventions were set up similarly to a prospective clinical trial. This study is the first of its kind in radiotherapy and this approach can contribute to discussions about the effectiveness of managerial interventions.
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    ABSTRACT: Stereotactic ablative body radiotherapy (SABR) is a non-invasive treatment option for inoperable patients or patients with irresectable liver tumors. Outcome and toxicity were evaluated retrospectively in this single-institution patient cohort. Between 2010 and 2014, 39 lesions were irradiated in 33 consecutive patients (18 male, 15 female, median age of 68 years). All the lesions were liver metastases (n = 34) or primary hepatocellular carcinomas (n = 5). The patients had undergone four-dimensional respiration-correlated PET-CT for treatment simulation to capture tumor motion. We analyzed local control with a focus on CT-based response at three months, one year and two years after treatment, looking at overall survival and the progression pattern. All patients were treated with hypofractionated image-guided stereotactic radiotherapy. The equivalent dose in 2 Gy fractions varied from 62.5 Gy to 150 Gy, delivered in 3-10 fractions (median dose 93.8 Gy, alpha/beta = 10). The CT-based regression pattern three months after radiotherapy revealed partial regression in 72.7% of patients with a complete remission in 27.3% of the cases. The site of first progression was predominantly distant. One- and two-year overall survival rates were 85.4% and 68.8%, respectively. No toxicity of grade 2 or higher according to the NCI Common Terminology Criteria for Adverse Events v4.0 was observed. SABR is a safe and efficient treatment for selected inoperable patients or irresectable tumors of the liver. Future studies should combine SABR with systemic treatment acting in synergy with radiation, such as immunological interventions or hypoxic cell radiosensitizers to prevent distant relapse. Copyright © 2014 Elsevier Ltd. All rights reserved.
    European Journal of Surgical Oncology 11/2014; 41(2). DOI:10.1016/j.ejso.2014.10.053 · 2.89 Impact Factor
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    ABSTRACT: Objective: Increased tumor metabolism and hypoxia are related to poor prognosis in solid tumors, including non-small cell lung cancer (NSCLC). PET imaging is a non-invasive technique frequently used to visualize and quantify tumor metabolism and hypoxia. The aim of this study was to perform an extensive comparison of tumor metabolism using FDG PET and hypoxia using HX4 PET imaging. Materials/Methods: FDG- and HX4-PET/CT images of 25 NSCLC patients were co-registered. At a global tumor-level, HX4 and FDG parameters were extracted from the gross-tumor-volume. The HX4-high fraction and high volume were defined using a tumor-to-blood ratio>1.4. This study used a SUV>50% of SUVmax for FDG-high fraction and high volume. We evaluated the spatial correlation between HX4 and FDG uptake within the tumor, to quantify the (mis)match between the volumes with high FDG and HX4 uptake. Results: At a tumor-level, significant correlations were observed between FDG and HX4 parameters. For the primary GTV, the HX4-high fraction was three times smaller compared to the FDG-high fraction. In 53% of the primary lesions, less than 1cm3 of the HX4-high-volume was outside the FDG-high volume; for 37% this volume was 1.9-12cm3. Remarkably, a distinct uptake pattern was observed in 11%, with large hypoxic volumes localized outside the FDG-high volume. Conclusion: Hypoxic tumor volumes are smaller than metabolic active volumes. Approximately half of the lesions showed a good spatial correlation between the PET tracers. In the other cases, a (partial)mismatch was observed. The addition of HX4-PET imaging has the potential to individualize patient treatment.
    Clinical Cancer Research 10/2014; DOI:10.1158/1078-0432.CCR-14-1524 · 8.19 Impact Factor
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    ABSTRACT: The importance of a safety culture to maximize safety is no longer questioned. However, achieving sustainable culture improvements are less evident. Evidence is growing for a multifaceted approach, where multiple safety interventions are combined. Lean management is such an integral approach to improve safety, quality and efficiency and therefore, could be expected to improve the safety culture. This paper presents the effects of lean management activities on the patient safety culture in a radiotherapy institute.
    European journal of oncology nursing: the official journal of European Oncology Nursing Society 09/2014; 19(1). DOI:10.1016/j.ejon.2014.08.001 · 1.79 Impact Factor
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    ABSTRACT: Objective: The aim of this review is to investigate the effect of timing of the reconstruction and radiotherapy, with respect to complication rate and cosmetic outcome, with a special focus on the timing of the placement of the definite implant. Methods: PubMed was searched for publications between January 2000 and December 2012. Of 37 eligible studies, timing of reconstruction, type, and incidence of complications were recorded. First, we calculated the weighted mean including confidence intervals for complications and cosmetic outcome overall, and for the following subgroups: (1) Autologous reconstruction after radiotherapy; (2) Definite implant reconstruction after radiotherapy; (3) Autologous reconstruction before radiotherapy; (4) Definite implant reconstruction before radiotherapy. A second analysis was performed using only studies that directly compared group 1 versus 3 and 2 versus 4. Results: A large variation in complication rates (8.7-70.0%) and in acceptable cosmetic outcome (41.4-93.3%) was reported. The first analysis showed more complications and a higher revision rate if an implant reconstruction was performed after radiotherapy; for autologous reconstruction fibrosis occurred more often if reconstruction was applied first. The second analysis showed no significant differences in total complication rate. Only implant failure occurred more often if applied after radiotherapy (odds ratio (OR) 3.03 [1.59-5.77]). No differences were found in both patient and physician satisfaction. Conclusions: A definite implant reconstruction placed before radiotherapy limits the rate of complications. For autologous reconstruction, less fibrosis is seen if reconstruction is performed after radiotherapy, but timing had no significant impact on total complication rate. (c) 2014 Elsevier Ltd. All rights reserved.
    European journal of cancer (Oxford, England: 1990) 08/2014; 50(16). DOI:10.1016/j.ejca.2014.07.023 · 4.82 Impact Factor
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    ABSTRACT: Purpose: To realize safe radiotherapy treatment, processes must be stabilized. Standard operating procedures (SOP'S) were expected to stabilize the treatment process and perceived task importance would increase sustainability in compliance. This paper presents the effects on compliance to safety related tasks of a process redesign based on lean principles. Method: Compliance to patient safety tasks was measured by video recording of actual radiation treatment, before (T-0), directly after (T-1) and 1.5 years after (T-2) a process redesign. Additionally, technologists were surveyed on perceived task importance and reported incidents were collected for three half-year periods between 2007 and 2009. Results: Compliance to four out of eleven tasks increased at T-1, of which improvements on three sustained (T-2). Perceived importance of tasks strongly correlated (0.82) to compliance rates at Ty. The two tasks, perceived as least important, presented low base-line compliance, improved (T-1), but relapsed at T-2. The reported near misses (patient-level not reached) on accelerators increased (P < 0.001) from 144 (2007) to 535 (2009), while the reported misses (patient-level reached) remained constant. Conclusions: Compliance to specific tasks increased after introducing SOP's and improvements sustained after 1.5 years, indicating increased stability. Perceived importance of tasks correlated positively to compliance and sustainability. Raising the perception of task importance is thus crucial to increase compliance. The redesign resulted in increased willingness to report incidents, creating opportunities for patient safety improvement in radiotherapy treatment.
    European journal of oncology nursing: the official journal of European Oncology Nursing Society 06/2014; 18(5). DOI:10.1016/j.ejon.2014.05.003 · 1.79 Impact Factor
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    ABSTRACT: In this open-label phase I study, the maximum-tolerated dose of cetuximab with concurrent chemoradiotherapy (C-CRT) in stage III non-small-cell lung cancer together with individualized, isotoxic accelerated radiotherapy (RT) was investigated. Patients with stage III non-small-cell lung cancer, World Health Organization performance status 0-1, forced expiratory volume in 1 second more than 50%, carbon monoxide diffusing capacity more than 50%, weight loss less than 10%, and no severe comorbidity were enrolled. Patients without progression after one to two cycles of gemcitabine-carboplatin were included and treated with cetuximab 400 mg/kg d7 and 250 mg/kg weekly together with RT and cisplatin (50 mg/m d1, 8; 40 mg/m d22)-vinorelbine for 5 weeks. Vinorelbine was escalated in three steps; (1) 10 mg/m d1, 8 and 8 mg/m d22, 29; (2) 20 mg/m d1, 8 and 8 mg/m d22, 29; (3) 20 mg/m d1, 8; 15 mg/m d22, 29. An individualized prescribed RT dose based on normal tissue dose constraints was applied (e.g., mean lung dose 19 Gy). The primary endpoint was the maximum-tolerated dose 3 months after the end of C-CRT; secondary endpoints were toxicity and metabolic response as assessed by positron emission tomography. Between September 2007 and October 2010, 25 patients (12 men, 13 women, mean age 59 years) were included. The mean RT dose was 62 ± 6.6 Gy. The vinorelbine dose could be escalated to dose level 3. Twelve of 25 patients experienced greater than or equal to grade 3 toxicity (esophagitis 3, rash 1, diarrhea 1, cough 1, dyspnea 1, vomiting 1, and pulmonary embolism 1). No dose-limiting toxicities were observed. One patient with a complete pathological response in dose level 3 developed a fatal hemoptysis 4 months after RT. Metabolic remissions were observed in 19 of 22 patients. C-CRT with cetuximab and cisplatin-vinorelbine is safe to deliver at full dose. The recommended phase II dose is therefore cetuximab 400 mg/m d7 and 250 mg/m weekly, cisplatin 50 mg/m d1, 8; 40 mg/m d22 and vinorelbine 20 mg/m d1, 8; 15 mg/m d22, 29 for 5 weeks together with RT.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 05/2014; 9(5):710-6. DOI:10.1097/JTO.0000000000000151 · 5.80 Impact Factor
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    ABSTRACT: Purpose To date studies do not agree on the effects of irradiation on bone mineral density. The aim of this study was to investigate changes in mandibular bone mineral density after irradiation in various doses with and without surgery. Materials and Methods The investigators implemented a descriptive animal experiment. The sample was composed of sixteen female Göttingen minipigs, randomly assigned into four groups, and were irradiated with equivalent doses of 0, 25, 50 and 70 Gray to the mandibular region. Three months after irradiation, mandibular left premolars and molars were removed and dental implants were placed. CT-scans were made before and 6 months after irradiation. The measured bone density was related to a bone phantom to calculate the bone mineral density quotient (BMDQ). The outcome variable was BMDQ. Other study variables were irradiation dose, and operation. Descriptive and univariate analyses were computed and the p value was set at 0,05. Results In the left hemimandible, compared to the control group a significant decrease in BMDQ was observed 0,01 (0Gy), -0,01 (25Gy), -0,06 (50Gy), and -0,11 (70Gy) (p=0,023). The right hemimandible compared to the control group, also showed significant decrease in BMDQ -0,02 (0Gy), -0,08 (25Gy), -0,09 (50Gy), and -0,11 (70Gy) (p=0,007). Conclusion This study presents a large animal model to simulate tissue reactions induced by various doses of irradiation in the mandible. We found a significant decrease in BMDQ after irradiation, but no significant correlation could be found between the irradiation dose and a decrease in BMDQ.
    Journal of Oral and Maxillofacial Surgery 05/2014; 72(11). DOI:10.1016/j.joms.2014.05.025 · 1.28 Impact Factor
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    ABSTRACT: Objectives Both bone and brain are frequent sites of metastasis in non-small cell lung cancer (NSCLC). Conflicting data exist whether EGFR mutant (+) patients are more prone to develop brain metastases or have a better outcome with brain metastases compared to EGFR/KRAS wild type (WT) or KRAS+ patients. For bone metastases this has not been studied. Methods In this retrospective case-control study all EGFR+ (exon 19 and 21) patients diagnosed at two pathology departments were selected (2004/2008 to 2012). For every EGFR+ patient a consecutive KRAS+ and WT patient with metastatic NSCLC (mNSCLC) was identified. Patients with another malignancy within 2 years of mNSCLC diagnosis were excluded. Data regarding age, gender, performance score, histology, treatment, bone/brain metastases diagnosis, skeletal related events (SRE) and subsequent survival were collected. Results 189 patients were included: 62 EGFR+, 65 KRAS+, 62 WT. 32%, 35% and 40% respectively had brain metastases (p = 0.645). Mean time to brain metastases was 20.8 [±12.0], 10.8 [±9.8], 16.4 [±10.2] months (EGFR + -KRAS+ p = 0.020, EGFR + -WT p = 0.321). Median post brain metastases survival was 12.1 [5.0-19.1], 7.6 [1.2-14.0], 10.7 [1.5-19.8] months (p = 0.674). 60%, 52% and 50% had metastatic bone disease (p = 0.528). Mean time to development of metastatic bone disease was 13.4 [±10.6], 23.3 [±19.4], 16.4 [±9.6] months (p = 0.201). Median post metastatic bone disease survival was 15.0 [10.6-20.3], 9.0 [5.2-12.9], 3.2 [0.0-6.9] months (p = 0.010). Time to 1st SRE was not significantly different. Conclusions Incidence of brain and bone metastases was not different between EGFR+, KRAS+ and WT patients. Post brain metastases survival, time from mNSCLC diagnosis to metastatic bone disease and 1st SRE did not differ either. Post metastatic bone disease survival was significantly longer in EGFR+ patients. Although prevention of SRE's is important for all patients, the latter finding calls for a separate study for SRE preventing agents in EGFR+ patients.
    Lung cancer (Amsterdam, Netherlands) 04/2014; 84(1). DOI:10.1016/j.lungcan.2014.01.006 · 3.74 Impact Factor
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    ABSTRACT: Radiation-esophagitis and weight loss are frequently observed toxicities in patients treated with concurrent chemo-radiotherapy (CT-RT) for non-small cell lung cancer (NSCLC) and might be related. The purpose was to investigate whether weight loss already starts early after initiation of CT-RT and precedes radiation-esophagitis. In a retrospective cohort, weight and esophagitis grade ≥2 were assessed during the first weeks of (CT-)RT in patients treated with concurrent (n = 102) or sequential (n = 92) therapy. In a prospective validation study, data on body weight, esophagitis grade ≥2, nutritional intake and muscle strength were obtained before, during and following CT-RT. In the retrospective cohort, early weight loss was observed in concurrently treated patients (p = 0.002), independent of esophagitis ≥ grade 2. Early weight loss was also observed in the prospective cohort (p = 0.003) and was not accompanied by decreases in nutritional intake. In addition lower limb muscle strength rapidly declined (p = 0.042). In the later weeks of treatment, further body weight loss occurred (p < 0.001) despite increased nutritional supplementation and body weight was only partly recovered after 4 weeks post CT-RT (p = 0.003). Weight loss during concurrent CT-RT for NSCLC starts early and prior to onset of esophagitis, requiring timely and intense nutritional rehabilitation.
    Journal of Cachexia, Sarcopenia and Muscle 01/2014; 5(2). DOI:10.1007/s13539-013-0127-5 · 7.41 Impact Factor
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    ABSTRACT: Purpose To realize safe radiotherapy treatment, processes must be stabilized. Standard operating procedures (SOP's) were expected to stabilize the treatment process and perceived task importance would increase sustainability in compliance. This paper presents the effects on compliance to safety related tasks of a process redesign based on lean principles. Method Compliance to patient safety tasks was measured by video recording of actual radiation treatment, before (T0), directly after (T1) and 1.5 years after (T2) a process redesign. Additionally, technologists were surveyed on perceived task importance and reported incidents were collected for three half-year periods between 2007 and 2009. Results Compliance to four out of eleven tasks increased at T1, of which improvements on three sustained (T2). Perceived importance of tasks strongly correlated (0.82) to compliance rates at T2. The two tasks, perceived as least important, presented low base-line compliance, improved (T1), but relapsed at T2. The reported near misses (patient-level not reached) on accelerators increased (P < 0.001) from 144 (2007) to 535 (2009), while the reported misses (patient-level reached) remained constant. Conclusions Compliance to specific tasks increased after introducing SOP's and improvements sustained after 1.5 years, indicating increased stability. Perceived importance of tasks correlated positively to compliance and sustainability. Raising the perception of task importance is thus crucial to increase compliance. The redesign resulted in increased willingness to report incidents, creating opportunities for patient safety improvement in radiotherapy treatment.
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    ABSTRACT: This study tests whether using a screening instrument improves referral to psychosocial care providers (e.g. psychologist) and facilitates patient-radiotherapist communication. A cluster randomized controlled trial was used. Fourteen radiotherapists were randomly allocated to the experimental or control group and 568 of their patients received care in accordance with the group to which their radiotherapist was allocated. Patients in the experimental group were asked to complete a screening instrument before and at the end of the radiation treatment period. All patients were requested to complete questionnaires concerning patient-physician communication after the first consultation and concerning psychosocial care 3 and 12 months post-intervention. Patients who completed the screening instrument were referred to social workers at an earlier stage than patients who did not (P<0.01). No effects were observed for numbers of referred patients, or for improved patient-radiotherapist communication. Our results suggest that a simple screening procedure can be valuable for the timely treatment of psychosocial problems in patients. Future efforts should be directed at appropriate timing of screening and enhancing physicians' awareness regarding the importance of identifying, discussing and treating psychosocial problems in cancer patients. Psychosocial screening can be enhanced by effective radiotherapist-patient communication.
    Patient Education and Counseling 08/2013; 93:: 289-297. DOI:10.1016/j.pec.2013.06.015 · 2.60 Impact Factor
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    ABSTRACT: This study examined the short-term and long-term effects of using a screening instrument on psychological distress and health-related quality of life (HRQoL) among cancer patients receiving radiotherapy. In addition, we investigated the effect of early psychosocial treatment on patients' overall health-related outcomes as previous research showed that patients in the screening condition were referred to a psychosocial caregiver at an earlier stage. A cluster randomised controlled trial with a randomisation at the levels of 14 radiotherapists, 568 patients was conducted. Patients were asked to complete questionnaires at 3 and 12 months follow-up. Mixed models analyses showed no significant intervention effects on patients' overall extent of psychosocial distress and HRQoL, both on the short and long terms. Post-hoc analyses revealed significant interactions of the intervention with early referral and improved HRQoL and anxiety, suggesting that earlier referral might influence short-term HRQoL and experienced anxiety in patients. Our results suggest that the use of a psychosocial screening instrument among patients receiving radiotherapy in itself does not sufficiently improve patients' health-related outcome. The effective delivery of psychosocial care depends upon several components such as identification of distress and successful implementation of screening procedures. One of the challenges is to get insight in the effects of early referral of cancer patients for psychosocial support because early referral might have a favourable effect on some of the patients' health-related outcomes. Copyright © 2013 John Wiley & Sons, Ltd.
    Psycho-Oncology 07/2013; DOI:10.1002/pon.3340 · 4.04 Impact Factor
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    ABSTRACT: BACKGROUND: Long-term survival can be obtained with local treatment of lung metastases from colorectal cancer. However, it is unclear as to what the optimal local therapy is: surgery, radiofrequency ablation (RFA) or stereotactic radiotherapy (SBRT). METHODS: A systematic review included 27 studies matching with the a priori selection criteria, the most important being ⩾50 patients and a follow-up period of ⩾24months. No SBRT studies were eligible. The review was therefore conducted on 4 RFA and 23 surgical series. RESULTS: Four of the surgical studies were prospective, all others were retrospective. No randomized trial was found. The reporting of data differed between the studies, which led to difficulties in the analyses. Treatment-related mortality rates for RFA and surgery were 0% and 1.4-2.4%, respectively, whereas morbidity rates were reported inconsistently but seemed the lowest for surgery. CONCLUSION: Due to the lack of phase III trials, no firm conclusions can be drawn, although most evidence supports surgery as the most effective treatment option. High-quality trials comparing currently used treatment modalities such as SBRT, RFA and surgery are needed to inform treatment decisions.
    Cancer Treatment Reviews 06/2013; DOI:10.1016/j.ctrv.2013.05.004 · 6.47 Impact Factor
  • Lung Cancer 05/2013; 80:S33–S34. DOI:10.1016/S0169-5002(13)70294-0 · 3.74 Impact Factor
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Publication Stats

898 Citations
244.71 Total Impact Points

Institutions

  • 2007–2014
    • Maastricht Universitair Medisch Centrum
      • Central Diagnostic Laboratory
      Maestricht, Limburg, Netherlands
    • Maastro Clinic
      Maestricht, Limburg, Netherlands
  • 2001–2014
    • Maastricht University
      • • GROW School for Oncology & Developmental Biology
      • • Department of Clinical Psychological Science
      Maestricht, Limburg, Netherlands