ACAnnelies Colliers

Annelies Colliers

*This is an algorithmically generated author record based on publicly available information.

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Previous Organizations / Institutes

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Annelies Colliers has a total of 174 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Did aetiology matter in illness duration and complications in patients presenting in primary care with acute respiratory tract infections early in the COVID-19 pandemic: An observational study in nine countries

    by Roderick P. Venekamp, Marinus J.C. Eijkemans, Nicolaas P.A. Zuithoff, Femke Böhmer, Slawomir Chlabicz, Annelies Colliers, Ana García-Sangenís, Lile Malania, Jozsef Pauer, Angela Tomacinschii, et al.

    Despite considerable research into COVID-19 sequelae, little is known about differences in illness duration and complications in patients presenting in primary care with symptoms of acute respiratory tract infections (RTI) that are and are not attributed to SARS-CoV-2 infection. To explore whether aetiology impacted course of illness and prediction of complications in patients presenting in primary care with symptoms of RTI early in the COVID-19 pandemic. Between April 2020-March 2021 general practitioners from nine European countries recruited consecutively contacting patients with RTI symptoms. At baseline, an oropharyngeal-nasal swab was obtained for aetiology determination using PCR after follow-up of 28 days. Time to self-reported recovery was analysed with Kaplan-Meier curves. Predictors (baseline variables of demographics, patient and disease characteristics) of a complicated course (composite of hospital admission and persisting signs/symptoms at 28 days follow-up) were explored with logistic regression modelling. Of 855 patients with RTI symptoms, 237 (27.7%) tested SARS-CoV-2 positive. The proportion not feeling fully recovered (15.6% vs 18.1%, p = 0.39), reporting being extremely tired (9.7% vs 12.8%, p = 0.21), and not having returned to usual daily activities (18.1% vs 14.4%, p = 0.18) at day 28 were comparable between SARS-CoV-2 positive (n = 237) and negative (n = 618) groups. However, among those feeling fully recovered (SARS-CoV-2 positive: 200 patients, SARS-CoV-2 negative: 506 patients), time to full recovery was significantly longer in SARS-CoV-2 patients (10.6 vs 7.7 days, p < 0.001). We found no evidence that predictors of a complicated course differed between groups (p = 0.07). Early in the pandemic, the proportion of patients not feeling fully recovered by 28 days was similar between SARS-CoV-2 positive and negative patients presenting in primary care with RTI symptoms, but it took somewhat longer for SARS-CoV-2 patients to feel fully recovered. More research is needed on predictors of a complicated course in RTI.

  • Open Access

    Qualitative study on shared decision making in cystitis management in general practice

    by Tessa Mzxk van Horrik, Annelies Colliers, Marco H Blanker, Eefje Gpm de Bont, Antoinette A van Driel, Bart J Laan, Suzanne E Geerlings, Roderick P Venekamp, Sibyl Anthierens, Tamara N Platteel

    Background: Cystitis is commonly treated with antibiotics, although non-antibiotic options could be considered for healthy non-pregnant women. Shared decision making (SDM) can be used in cystitis management to discuss the various treatment options but is not frequently applied in general practice. Aim: To identify barriers and facilitators for applying SDM in cystitis management in general practice. Design & setting: Qualitative explorative research in general practice with healthcare professionals (HCPs; GPs and GP assistants) and healthy non-pregnant women with a recent history of cystitis (patients). Method: Individual semi-structured interviews were conducted between May and October 2022. We applied a combination of thematic and framework analysis. Results: Ten GPs, seven GP assistants, and 15 patients were interviewed. We identified the following three main barriers and one key facilitator: (1) applying SDM is deemed inefficient; (2) HCPs assume that patients expect antibiotic treatment and some HCPs consider non-antibiotic treatment inferior; (3) patients are largely unaware of the various non-antibiotic treatment options for cystitis; and (4) HCPs recognise some benefits of applying SDM in cystitis management, including reduced antibiotic use and improved patient empowerment, and patients appreciate involvement in treatment decisions, but preferences for SDM vary. Conclusion: SDM is infrequently applied in cystitis treatment in general practice owing to the current focus on efficient cystitis management that omits patient contact, HCPs’ perceptions, and patient unawareness. Nevertheless, both HCPs and patients recognise the long-term benefits of applying SDM in cystitis management. Our findings facilitate the development of tailored interventions to increase the application of SDM, which should be co-created with HCPs and patients, and fit into the current efficient cystitis management.


  • Open Access

    Improving antibiotic prescribing quality in out-of-hours primary care: a mixed-methods study using participatory action research

    by Annelies Colliers, Samuel Coenen, Stefan Teughels, Yentry Boogaerts, Olivia Vandeput, Anouk Tans, Helene Vermeulen, Roy Remmen, Hilde Philips, Sibyl Anthierens

    Background: During out-of-hours (OOH) primary care, GPs overprescribe antibiotics for respiratory tract infections (RTIs). Many interventions have been shown to improve antibiotic prescribing quality, but their implementation in practice remains difficult. Participatory action research (PAR) aims to explore, implement and evaluate change in practice with an active involvement of local stakeholders, while generating knowledge through experience. Objectives: To evaluate whether PAR improves antibiotic prescribing quality for RTIs during OOH primary care and simultaneously identify the pivotal lessons learned. Methods: A mixed-methods study with a PAR approach in three OOH GP cooperatives (GPCs). Each GPC co-created a multifaceted intervention focusing on improving antibiotic use for RTIs through plan-do-study-act cycles. We quantified antibiotic prescribing quality indicators and formulated the lessons learned from a qualitative process analysis. Results: Interventions were chosen with the GPs and adapted to be context-relevant. The willingness to work on quality and engagement of local stakeholders led to ownership of the project, but was time-consuming. In one GPC, antibiotic prescribing significantly decreased for tonsillitis, bronchitis, otitis media and acute upper RTI. In all three GPCs, use of guideline-recommended antibiotics for otitis media significantly increased. Conclusions: Implementing multifaceted interventions through PAR can lower total and increase guideline-recommended antibiotic prescribing for RTIs in OOH primary care. Co-creating interventions with GPs to suit local needs is feasible, but reaching all GPs targeted is challenging.


  • Open Access

    The experiences of patients ill with COVID-19-like symptoms and the role of testing for SARS-CoV-2 in supporting them: A qualitative study in eight European countries during the first wave of the pandemic

    by Melanie E. Hoste, Marta Wanat, Nina Gobat, Marilena Anastasaki, Femke Böhmer, Sławomir Chlabicz, Annelies Colliers, Karen Farrell, Maria-Nefeli Karkana, John Kinsman, et al.

    Access to testing during the first wave of the COVID-19 pandemic was limited, impacting patients with COVID-19-like symptoms. Current qualitative studies have been limited to one country or were conducted outside Europe. To explore - in eight European countries - the experiences of patients consulting in primary care with COVID-19-like symptoms during the first wave of the pandemic. Sixty-six semi-structured interviews, informed by a topic guide, were conducted by telephone or in person between April and July 2020. Patients with COVID-19-like symptoms were purposively recruited in primary care sites in eight countries and sampled based on age, gender, and symptom presentation. Deductive and inductive thematic analysis techniques were used to develop a framework representing data across settings. Data adequacy was attained by collecting rich data. Seven themes were identified, which described the experiences of patients consulting. Two themes are reported in this manuscript describing the role of COVID-19 testing in this experience. Patients described significant distress due to their symptoms, especially those at higher risk of complications from COVID-19, and those with severe symptoms. Patients wanted access to testing to identify the cause of their illness and minimise the burden of managing uncertainty. Some patients testing positive for COVID-19 assumed they would be immune from future infection. Patients experiencing novel and severe symptoms, particularly those with comorbidities, experienced a significant emotional and psychological burden due to concerns about COVID-19. Testing provided reassurance over health status and helped patients identify which guidance to follow. Testing positive for SARS-CoV-2 led to some patients thinking they were immune from future infection, thus influencing subsequent behaviour.


  • Open Access

    Cost-effectiveness of adding oseltamivir to primary care for influenza-like-illness: economic evaluation alongside the randomised controlled ALIC4E trial in 15 European countries

    by Xiao Li, Joke Bilcke, Alike W. van der Velden, Robin Bruyndonckx, Samuel Coenen, Emily Bongard, Muirrean de Paor, Slawomir Chlabicz, Maciek Godycki-Cwirko, Nick Francis, et al.

    Background: Oseltamivir is usually not often prescribed (or reimbursed) for non-high-risk patients consulting for influenza-like-illness (ILI) in primary care in Europe. We aimed to evaluate the cost-effectiveness of adding oseltamivir to usual primary care in adults/adolescents (13 years +) and children with ILI during seasonal influenza epidemics, using data collected in an open-label, multi-season, randomised controlled trial of oseltamivir in 15 European countries.Methods: Direct and indirect cost estimates were based on patient reported resource use and official country-specific unit costs. Health-Related Quality of Life was assessed by EQ-5D questionnaires. Costs and quality adjusted life-years (QALY) were bootstrapped (N = 10,000) to estimate incremental cost-effectiveness ratios (ICER), from both the healthcare payers’ and the societal perspectives, with uncertainty expressed through probabilistic sensitivity analysis and expected value for perfect information (EVPI) analysis. Additionally, scenario (self-reported spending), comorbidities subgroup and country-specific analyses were performed.Results: The healthcare payers’ expected ICERs of oseltamivir were €22,459 per QALY gained in adults/adolescents and €13,001 in children. From the societal perspective, oseltamivir was cost-saving in adults/adolescents, but the ICER is €8,344 in children. Large uncertainties were observed in subgroups with comorbidities, especially for children. The expected ICERs and extent of decision uncertainty varied between countries (EVPI ranged €1–€35 per patient).Conclusion: Adding oseltamivir to primary usual care in Europe is likely to be cost-effective for treating adults/adolescents and children with ILI from the healthcare payers’ perspective (if willingness-to-pay per QALY gained > €22,459) and cost-saving in adults/adolescents from a societal perspective.


  • Open Access

    Safety netting advice for respiratory tract infections in out-of-hours primary care: A qualitative analysis of consultation videos

    by Annelies Colliers, Hilde Philips, Katrien Bombeke, Roy Remmen, Samuel Coenen, Sibyl Anthierens

    General practitioners (GPs) use safety netting advice to communicate with patients when and how to seek further help when their condition fails to improve or deteriorate. Although many respiratory ...


  • Open Access

    Antibiotic Prescribing Trends in Belgian Out-of-Hours Primary Care during the COVID-19 Pandemic: Observational Study Using Routinely Collected Health Data

    by Annelies Colliers, Jeroen De Man, Niels Adriaenssens, Veronique Verhoeven, Sibyl Anthierens, Hans De Loof, Hilde Philips, Samuel Coenen, Stefan Morreel

    Antibiotic overprescribing is one of the main drivers of the global and growing problem of antibiotic resistance, especially in primary care and for respiratory tract infections (RTIs). RTIs are the most common reason for patients to consult out-of-hours (OOH) primary care. The COVID-19 pandemic has changed the way general practitioners (GPs) work, both during office hours and OOH. In Belgian OOH primary care, remote consultations with the possibility of issuing prescriptions and telephone triage were implemented. We aimed to describe the impact of COVID-19 on GPs’ antibiotic prescribing during OOH primary care. In an observational study, using routinely collected health data from GP cooperatives (GPCs) in Flanders, we analyzed GPs’ antibiotic prescriptions in 2019 (10 GPCs) and 2020 (20 GPCs) during OOH consultations (telephone and face-to-face). We used autoregressive integrated moving average (ARIMA) modeling to identify any changes after lockdowns were implemented. In total, 388,293 contacts and 268,430 prescriptions were analyzed in detail. The number of antibiotic prescriptions per weekend, per 100,000 population was 11.47 (95% CI: 9.08–13.87) or 42.9% lower after compared to before the implementation of lockdown among all contacts. For antibiotic prescribing per contact, we found a decrease of 12.2 percentage points (95% CI: 10.6–13.7) or 56.5% among all contacts and of 5.3 percentage points (95% CI: 3.7–6.9) or 23.2% for face-to-face contacts only. The decrease in the number of prescriptions was more pronounced for cases with respiratory symptoms that corresponded with symptoms of COVID-19 and for antibiotics that are frequently prescribed for RTIs, such as amoxicillin (a decrease of 64.9%) and amoxicillin/clavulanate (a decrease of 38.1%) but did not appear for others such as nitrofurantoin. The implementation of COVID-19 lockdown measures coincided with an unprecedented drop in the number of antibiotic prescriptions, which can be explained by a decrease in face-to-face patient contacts, as well as a lower number of antibiotics prescriptions per face-to-face patient contact. The decrease was seen for antibiotics used for RTIs but not for nitrofurantoin, the first-choice antibiotic for urinary tract infections.


  • Open Access

    Antibiotic Prescribing and Doctor-Patient Communication During Consultations for Respiratory Tract Infections: A Video Observation Study in Out-of-Hours Primary Care

    by Annelies Colliers, Katrien Bombeke, Hilde Philips, Roy Remmen, Samuel Coenen, Sibyl Anthierens

    Objective: Communication skills can reduce inappropriate antibiotic prescribing, which could help to tackle antibiotic resistance. General practitioners often overestimate patient expectations for an antibiotic. In this study, we describe how general practitioners and patients with respiratory tract infections (RTI) communicate about their problem, including the reason for encounter and ideas, concerns, and expectations (ICE), and how this relates to (non-)antibiotic prescribing in out-of-hours (OOH) primary care.Methods: A qualitative descriptive framework analysis of video-recorded consultations during OOH primary care focusing on doctor-patient communication.Results: We analyzed 77 videos from 19 general practitioners. General practitioners using patient-centered communication skills received more information on the perspective of the patients on the illness period. For some patients, the reason for the encounter was motivated by their belief that a general practitioner (GP) visit will alter the course of their illness. The ideas, concerns, and expectations often remained implicit, but the concerns were expressed by the choice of words, tone of voice, repetition of words, etc. Delayed prescribing was sometimes used to respond to implicit patient expectations for an antibiotic. Patients accepted a non-antibiotic management plan well.Conclusion: Not addressing the ICE of patients, or their reason to consult the GP OOH, could drive assumptions about patient expectations for antibiotics early on and antibiotic prescribing later in the consultation.


  • Open Access

    Primary care for patients with respiratory tract infection before and early on in the COVID-19 pandemic: an observational study in 16 European countries

    by Alike W van der Velden, Eva A Bax, Emily Bongard, Rune Munck Aabenhus, Marilena Anastasaki, Sibyl Anthierens, Anca Balan, Femke Böhmer, Pascale Bruno, Slawomir Chlabicz, et al.

    Objective To describe primary health care (consultation characteristics and management) for patients contacting their general practitioner (GP) with a respiratory tract infection (RTI) early on in the COVID-19 pandemic in contrasting European countries, with comparison to prepandemic findings. Setting Primary care in 16 countries (79 practices), when no routine SARS-CoV-2 testing was generally available. Design and participants Before (n=4376) and early in the pandemic (n=3301), patients with RTI symptoms were registered in this prospective audit study. Outcome measures Consultation characteristics (type of contact and use of PPE) and management characteristics (clinical assessments, diagnostic testing, prescribing, advice and referral) were registered. Differences in these characteristics between countries and between pandemic and prepandemic care are described. Results Care for patients with RTIs rapidly switched to telephone/video consultations (10% in Armenia, 91% in Denmark), and when consultations were face-to-face, GPs used PPE during 97% (95% CI 96% to 98%) of contacts. Laboratory testing for SARS-CoV-2 in primary care patients with RTIs was rapidly implemented in Denmark (59%) and Germany (31%), while overall testing for C reactive protein decreased. The proportion of patients prescribed antibiotics varied considerably between countries (3% in Belgium, 48% in UK) and was lower during the pandemic compared with the months before, except for Greece, Poland and UK. GPs provided frequent and varied COVID-related advice and more frequently scheduled a follow-up contact (50%, 95% CI 48% to 52%). GPs reported a slightly higher degree of confidence in the likely effectiveness of their management in face-to-face (73% (very) confident, 95% CI 71% to 76%) than in virtual consultations (69%, 95% CI 67% to 71%). Conclusions Despite between-country variation in consultation characteristics, access to SARS-CoV-2 laboratory testing and medication prescribing, GPs reported a high degree of confidence in managing their patients with RTIs in the emerging pandemic. Insight in the highly variable pandemic responses, as measured in this multicountry audit, can aid in fine-tuning national action and in coordinating a pan-European response during future pandemic threats.