Peter C. Wierenga
University of Amsterdam
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International Journal of Medical Informatics | 2010
Reza Khajouei; Niels Peek; Peter C. Wierenga; M. J. Kersten; Monique W. M. Jaspers
OBJECTIVES To study the effect of predefined order sets on the efficiency of computerized medication ordering, and to analyze the effect of different types of usability problems on ordering efficiency. METHODS Crossover study to comparing the efficiency of two methods of ordering (with and without use of predefined order sets) in a laboratory setting using a computerized physician order entry system (CPOE). The excess number of mouse clicks and keystrokes (the difference in number of mouse clicks and keystrokes needed by each physician and the minimally required numbers to accomplish the ordering tasks) for each method was measured and per physician, occurrences of usability problems during the task sessions were recorded. Observed usability problems were categorized using Zhang et al.s heuristic principles of good user interface design. The effect of different types of usability problems on the excess number of mouse clicks and keystrokes was statistically analyzed. RESULTS The median excess number of mouse clicks and keystrokes needed by physicians was 6.2 times lower in the method with predefined order sets (p<0.01). The excess number of mouse clicks and keystrokes was significantly increased by vague and erroneous system messages with a factor of 2.62 (95% CI 2.24-3.07), the use of unfamiliar language and terminology by a factor of 1.28 (95% CI 1.14-1.43), and non-informative system feedback by a factor of 1.15 (95% CI 1.03-1.28), respectively. Other categories of usability problems had little influence on ordering efficiency. CONCLUSIONS Predefined order sets can improve the efficiency of computerized ordering by reducing the excess number of mouse clicks and keystrokes. However, the efficiency of computerized ordering can be significantly impaired by usability problems due to vague and incorrect system messages, unfamiliar language, and non-informative system feedback.
PLOS ONE | 2011
Marjan Askari; Peter C. Wierenga; Saied Eslami; Stephanie Medlock; Sophia E. de Rooij; Ameen Abu-Hanna
Background Care of the elderly is recognized as an increasingly important segment of health care. The Assessing Care Of Vulnerable Elderly (ACOVE) quality indicators (QIs) were developed to assess and improve the care of elderly patients. Objectives The purpose of this review is to summarize studies that assess the quality of care using QIs from or based on ACOVE, in order to evaluate the state of quality of care for the reported conditions. Methods We systematically searched MEDLINE, EMBASE and CINAHL for English-language studies indexed by February 2010. Articles were included if they used any ACOVE QIs, or adaptations thereof, for assessing the quality of care. Included studies were analyzed and relevant information was extracted. We summarized the results of these studies, and when possible generated an overall conclusion about the quality of care as measured by ACOVE for each condition, in various settings, and for each QI. Results Seventeen studies were included with 278 QIs (original, adapted or newly developed). The quality scores showed large variation between and within conditions. Only a few conditions showed a stable pass rate range over multiple studies. Overall, pass rates for dementia (interquartile range (IQR): 11%–35%), depression (IQR: 27%–41%), osteoporosis (IQR: 34%–43%) and osteoarthritis (IQR: 29–41%) were notably low. Medication management and use (range: 81%–90%), hearing loss (77%–79%) and continuity of care (76%–80%) scored higher than other conditions. Out of the 278 QIs, 141 (50%) had mean pass rates below 50% and 121 QIs (44%) had pass rates above 50%. Twenty-three percent of the QIs scored above 75%, and 16% scored below 25%. Conclusions Quality of care per condition varies markedly across studies. Although there has been much effort in improving the care for elderly patients in the last years, the reported quality of care according to the ACOVE indicators is still relatively low.
Drugs & Aging | 2012
Peter C. Wierenga; Bianca M. Buurman; Juliette L. Parlevliet; Barbara C. van Munster; Susanne M. Smorenburg; Sharon K. Inouye; Sophia E. de Rooij
BACKGROUND Elderly patients are at a 4-fold higher risk of adverse drug events (ADEs) and drug-related hospitalization. Hospitalization of an elderly patient is often preceded by geriatric syndromes, like falls or delirium. OBJECTIVES The primary aim of this study was to investigate whether geriatric syndromes were associated with ADEs in acutely admitted elderly patients. METHODS Consecutive medical patients, aged 65 years or more, who were acutely admitted, were enrolled. An initial multidisciplinary evaluation was completed and baseline characteristics were collected. A fall before admission was retrieved from medical charts. Delirium was determined by the Confusion Assessment Method. RESULTS A total of 641 patients were included. Over 25% had an ADE present at admission, 26% presented with delirium and 12% with a fall. Delirium was associated with the use of antidepressants, antipsychotics and antiepileptics. In all ADEs (n = 167), ADEs were associated with a fall, with non-steroidal anti-inflammatory drugs or diuretics, but not with pre-existing functioning, delirium or older age. For ADEs involving psychoactive medication (n = 35), an association was found between delirium, falls, opioids and antipsychotics in bivariate analyses. A fall just before hospitalization (odds ratio [OR] 3.69 [95% CI 1.41, 9.67]), antipsychotics (OR 3.70 [95% CI 1.19, 11.60]) and opioids (OR 14.57 [95% CI 2.02, 105.30]) remained independently associated with an ADE involving psychoactive medication. CONCLUSION This prospective study demonstrated that, in a cohort of elderly hospital patients, a fall before admission and prevalent delirium are associated with several pharmacological groups and/or with ADE-related hospital admission.
Pharmacoepidemiology and Drug Safety | 2013
Marjan Askari; Saied Eslami; Mathijs Louws; Peter C. Wierenga; Dave A. Dongelmans; Rob Kuiper; Ameen Abu-Hanna
Drug‐drug interactions (DDIs) may compromise patient safety. However, there are no good estimates of their frequency or understanding of their nature in the intensive care unit (ICU). The objective of this study was to determine the frequency and nature of potential DDIs (pDDIs) in the ICU when assessed in light of documented and perceived clinical relevance.
International Journal of Medical Informatics | 2011
Stephanie Medlock; Dedan Opondo; Saeid Eslami; Marjan Askari; Peter C. Wierenga; Sophia E. de Rooij; Ameen Abu-Hanna
PURPOSE The aim of this study was to create a step-by-step method for transforming clinical rules for use in decision support, and to validate this method for usability and reliability. METHODS A sample set of clinical rules was identified from the relevant literature. Using an iterative approach with a focus group of mixed clinical and informatics experts, a method was developed for assessing and formalizing clinical rules. Two assessors then independently applied the method to a separate validation set of rules. Usability was assessed in terms of the time required and the error rate, and reliability was assessed by comparing the results of the two assessors. RESULTS The resulting method, called the Logical Elements Rule Method, consists of 7 steps: (1) restate the rule proactively; (2) restate the rule as a logical statement (preserving key phrases); (3) assess for conflict between rules; (4) identify concepts which are not needed; (5) classify concepts as crisp or fuzzy, find crisp definitions corresponding to fuzzy concepts, and extract data elements from crisp concepts; (6) identify rules which are related by sharing patients, actions, etc.; (7) determine availability of data in local systems. Validation showed that the method was usable with rules from various sources and clinical conditions, and reliable between users provided that the users agree on a terminology and agree on when the rule will be evaluated. CONCLUSIONS A method is presented to assist in assessing clinical rules for their amenability to decision support, and formalizing the rules for implementation. Validation shows that the method is usable and reliable between users. Use of a terminology increases reliability but also the error rate. The method is useful for future developers of systems which offer decision support based on clinical rules.
PLOS ONE | 2013
Joanna E. Klopotowska; Peter C. Wierenga; Clementine C. M. Stuijt; Lambertus Arisz; Marcel G. W. Dijkgraaf; Paul F. M. Kuks; Henk Asscheman; Sophia E. de Rooij; Loraine Lie-A-Huen; Susanne M. Smorenburg
Background Older patients are at high risk for experiencing Adverse Drug Events (ADEs) during hospitalization. To be able to reduce ADEs in these vulnerable patients, hospitals first need to measure the occurrence of ADEs, especially those that are preventable. However, data on preventable ADEs (pADEs) occurring during hospitalization in older patients are scarce, and no ‘gold standard’ for the identification of ADEs exists. Methodology The study was conducted in three hospitals in the Netherlands in 2007. ADEs were retrospectively identified by a team of experts using a comprehensive and structured patient chart review (PCR) combined with a trigger-tool as an aid. This ADE identification strategy was applied to a cohort of 250 older hospitalized patients. To estimate the intra- and inter-rater reliabilities, Cohen’s kappa values were calculated. Principal Findings In total, 118 ADEs were detected which occurred in 62 patients. This ADE yield was 1.1 to 2.7 times higher in comparison to other ADE studies in older hospitalized patients. Of the 118 ADEs, 83 (70.3%) were pADEs; 51 pADEs (43.2% of all ADEs identified) caused serious patient harm. Patient harm caused by ADEs resulted in various events. The overall intra-rater agreement of the developed strategy was substantial (κ = 0.74); the overall inter-rater agreement was only fair (κ = 0.24). Conclusions/Significance The ADE identification strategy provided a detailed insight into the scope of ADEs occurring in older hospitalized patients, and showed that the majority of (serious) ADEs can be prevented. Several strategy related aspects, as well as setting/study specific aspects, may have contributed to the results gained. These aspects should be considered whenever ADE measurements need to be conducted. The results regarding pADEs can be used to design tailored interventions to effectively reduce harm caused by medication errors. Improvement of the inter-rater reliability of a PCR remains challenging.
Pediatric Anesthesia | 2011
Elles M. Kemper; Maruschka P. Merkus; Peter C. Wierenga; Petra C. Van Rijn; Desiree B. M. van der Werff; Loraine Lie-A-Huen; Martin Offringa
In daily practice, it is difficult to find a registered drug for children, because about 70% of the drugs prescribed in children are not studied, off‐label or unlicensed in this age group. Clinical trials have usually been performed in adults, and then in daily practice dosages are adjusted for children without proper studies in that age group. In some countries, national formularies are being established to overcome the existing variance in prescribing between physicians. Complicating factors in finding the correct dosage for children include the heterogeneity between different age groups in the developmental stages of the organs influencing the absorption, distribution, metabolism, and excretion as well as differences in body composition during growth. Growth may also influence the effects and adverse effects of a drug used in a child. For oral administration of drugs in children, the bioavailability, the taste, the composition, and the absence of toxic ingredients for that age group are additional important factors. The EU has recently introduced legislation to stimulate the pharmaceutical industry to investigate the pharmacological effect and safety of new medicines in children. In response to this legislation, research networks are being established to provide the optimal infrastructure for pediatric drug investigation. The goals of this paper are to review the current problems in daily practice and to address the needs for evidence based pharmacotherapy in children.
Drug Safety | 2009
Peter C. Wierenga; Loraine Lie-A-Huen; Sophia E. de Rooij; Niek S. Klazinga; Henk-Jan Guchelaar; Susanne M. Smorenburg
AbstractBackground: To improve medication safety effectively, one should systematically analyse and assess the risks for medication errors and determine the possible causes. So far, no risk-analysis instrument exists in healthcare that can be used to analyse and visualize risks, causes and consequences of potential adverse events in a prospective manner. In high-risk industries such as petrochemistry and aviation, the Bow-Tie model is frequently used. This model combines causes, errors, preventive and recovery measures, and consequences in one model and gives insight into the magnitude and causes of existing safety risks. The aim of our project was to study the usefulness of the Bow-Tie model in the hospital setting for prospective analysis of risks in the medication process in order to develop a practicable method. Methods: The model was first adapted to the clinical setting. Thereafter, the risk-analysis model was applied in a large tertiary teaching hospital in multi-disciplinary sessions. The sessions and risk-analysis method were evaluated on the following aspects: applicability, comprehensibility, creation of awareness in and motivation of participants, and the capability of the ‘system approach’ (the approach taken by the Bow-Tie model, which focuses on the conditions under which individuals work and tries to build defences to avert errors or mitigate their effects, in contrast to a ‘person approach’, which focuses on errors of individuals, blaming them for forgetfulness, inattention etc.). Based on this evaluation, the risk analysis method was adjusted and consecutively applied in a general teaching hospital. After evaluation of the sessions in the second hospital a recommended method for risk analysis with the Bow-Tie model was defined. Results: The risk-analysis method with the Bow-Tie model in the first hospital gave insight into many medication safety-related risks. However, the method was insufficient on comprehensibility and on the creation of awareness and motivation owing to a great number of determined risks which made thorough analysis, drawing of Bow-Ties and prioritizing difficult. The adjusted method in the second hospital focused more on the in-depth analysis of a small number of important safety issues of a department with specific attention for underlying causes. This approach was considered better in applicability, comprehensibility and the creation of awareness. Furthermore, by analyzing underlying causes, more attention could be paid to latent conditions (which can translate into error-provoking conditions) within the system. Conclusion: We found the Bow-Tie to be an appropriate model for prospective risk analysis of medication safety in a hospital. By applying the model in two hospitals consecutively we developed a feasible method for risk-analysis sessions. Key factors of this recommended method are a focus on the prioritized selection of safety issues and specific attention to latent conditions within the system by analysing these safety issues in depth to the root causes with the help of the Bow-Tie model.
Drugs & Aging | 2011
Peter C. Wierenga; Joanna E. Klopotowska; Susanne M. Smorenburg; Hendrikus J. M. van Kan; Yuma A. Bijleveld; Marcel G. W. Dijkgraaf; Sophia E. de Rooij
Background: In 2001, the ACOVE (Assessing Care Of Vulnerable Elders) quality indicators (QIs) were developed in the US to measure the quality of care of vulnerable elderly patients. However, the ACOVE QI set was developed mainly to assess the overall quality of care of community-dwelling vulnerable elders (as opposed to hospitalized elderly). Therefore, they need to be adapted when used in a non-US hospital setting. In addition, the ACOVE QIs depend on patient and caretaker interviews to assess the quality of care.Objectives: The aim of this study was to develop and validate a set of explicitly phrased QIs to measure (without the need for interviews) the quality of pharmaceutical care of elderly hospitalized patients in the Netherlands.Study Design: The QI set was developed based on the ACOVE QIs, Dutch national guidelines, evidence from the literature and expert opinion. The QI set focused on in-hospital pharmaceutical care and was evaluated in terms of whether the QIs were able to assess the quality of care using medical records and a hospital information system. In three review rounds, the QI set was adapted and judged on face and content validity. The feasibility of implementation of the QI set and inter-rater reliability were determined.Setting: The study was conducted between September 2007 and August 2008 in a tertiary 1002-bed university hospital.Research Team: Two pharmacists were responsible for the selection and adaptation of QIs. An internist-geriatrician, a physician with experience in quality assurance and internal medicine and a senior hospital pharmacist formed the expert panel responsible for reviewing the QIs.Measurements: Fleiss’ κ values and the intraclass correlation coefficient were calculated for inter-rater reliability.Results: An 87-item QI set was accepted by the expert panel. Of this set, 49 QIs were based on ACOVE QIs and 38 QIs were newly added. The QI set demonstrated excellent inter-rater reliability and good feasibility.Conclusions: We developed a valid and reliable set of QIs to efficiently assess the quality of the in-hospital pharmaceutical care provided to elderly Dutch patients.
International Journal of Medical Informatics | 2011
Reza Khajouei; Peter C. Wierenga; Arie Hasman; Monique W. M. Jaspers