Ondrej Majek

Dr. Ondrej Majek


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 May 2020 in Journal of Medical Internet Research
Verified
Journal Article
Open access
MKMartin Komenda
Martin Komenda
VBVojtěch Bulhart
Vojtěch Bulhart
MKMatěj Karolyi
Matěj Karolyi
JJJiří Jarkovský
Jiří Jarkovský
JMJan Mužík
Jan Mužík
LDLadislav Dušek
Ladislav Dušek
Background: The beginning of the coronavirus disease (COVID-19) epidemic dates back to December 31, 2019, when the first cases were reported in the People’s Republic of China. In the Czech Republic, the first three cases of infection with the novel coronavirus were confirmed on March 1, 2020. The joint effort of state authorities and researchers gave rise to a unique team, which combines methodical knowledge of real-world processes with the know-how needed for effective processing, analysis, and online visualization of data. Objective: Due to an urgent need for a tool that presents important reports based on valid data sources, a team of government experts and researchers focused on the design and development of a web app intended to provide a regularly updated overview of COVID-19 epidemiology in the Czech Republic to the general population. Methods: The cross-industry standard process for data mining model was chosen for the complex solution of analytical processing and visualization of data that provides validated information on the COVID-19 epidemic across the Czech Republic. Great emphasis was put on the understanding and a correct implementation of all six steps (business understanding, data understanding, data preparation, modelling, evaluation, and deployment) needed in the process, including the infrastructure of a nationwide information system; the methodological setting of communication channels between all involved stakeholders; and data collection, processing, analysis, validation, and visualization. Results: The web-based overview of the current spread of COVID-19 in the Czech Republic has been developed as an online platform providing a set of outputs in the form of tables, graphs, and maps intended for the general public. On March 12, 2020, the first version of the web portal, containing fourteen overviews divided into five topical sections, was released. The web portal’s primary objective is to publish a well-arranged visualization and clear explanation of basic information consisting of the overall numbers of performed tests, confirmed cases of COVID-19, COVID-19-related deaths, the daily and cumulative overviews of people with a positive COVID-19 case, performed tests, location and country of infection of people with a positive COVID-19 case, hospitalizations of patients with COVID-19, and distribution of personal protective equipment. Conclusions: The online interactive overview of the current spread of COVID-19 in the Czech Republic was launched on March 11, 2020, and has immediately become the primary communication channel employed by the health care sector to present the current situation regarding the COVID-19 epidemic. This complex reporting of the COVID-19 epidemic in the Czech Republic also shows an effective way to interconnect knowledge held by various specialists, such as regional and national methodology experts (who report positive cases of the disease on a daily basis), with knowledge held by developers of central registries, analysts, developers of web apps, and leaders in the health care sector.

Verified
Journal Article
Open access
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KBKATHARINA Beyer
KATHARINA Beyer
RLRenée C.A. Leenen
Renée C.A. Leenen
LVLionne Venderbos
Lionne Venderbos
JHJozien Helleman
Jozien Helleman
FDFréderique Béatrice Denijs
Fréderique Béatrice Denijs
OCon behalf of the PRAISE-U Consortium
on behalf of the PRAISE-U Consortium
With the new policy recommendation in 2022 to explore the possibilities of screening for prostate cancer by the European Commission, the landscape for prostate cancer early detection is evolving. In line with this recommendation, the PRAISE-U project aims to evaluate the early detection and diagnosis of prostate cancer through customised and risk-based screening programmes, with the goal to align protocols across European Union member states. This systematic review is part of the PRAISE-U project, with the goal to review the policy, medical guideline recommendations, and the current level of opportunistic screening presented in the scientific literature on prostate cancer early detection from 2016 to 2023 in European Union member states. An extensive literature search was performed on 1 June 2023 in a large number of databases, including Embase.com, Medline (Ovid), Web of Science Core Collection, Google Scholar, and Policy Commons. We identified 318 articles (qualitative, quantitative, and reviews), of which 41 were included in the full-text screening. Seventeen articles were ultimately identified as eligible for inclusion. The included articles revealed significant variations towards PSA-based early detection policies for prostate cancer in nine European countries. Despite official recommendations, opportunistic screening was prevalent across all nine countries regardless of recommendations for or against PSA-based early detection. This systematic review suggests that the current early detection policies are not fit for purpose. High levels of opportunistic screening and overdiagnosis persist, prompting policy recommendations for standardised guidelines, informed decision making, and increased awareness to improve efficiency and effectiveness in early detection.

8 July 2022 in PLOS ONE
Verified
Journal Article
Open access
PDF file
LBLuděk Berec
Luděk Berec
MŠMartin Šmíd
Martin Šmíd
LPLenka Přibylová
Lenka Přibylová
OMOndrej Majek
Ondrej Majek
TPTomáš Pavlík
Tomáš Pavlík
JTJan Trnka
Jan Trnka
Studies demonstrating the waning of post-vaccination and post-infection immunity against covid-19 generally analyzed a limited range of vaccines or subsets of populations. Using Czech national health data from the beginning of the covid-19 pandemic till November 20, 2021 we estimated the risks of reinfection, breakthrough infection, hospitalization and death by a Cox regression adjusted for sex, age, vaccine type and vaccination status. Vaccine effectiveness against infection declined from 87% at 0-2 months after the second dose to 53% at 7-8 months for BNT162b2 vaccine, from 90% at 0-2 months to 65% at 7-8 months for mRNA-1273, and from 83% at 0-2 months to 55% at 5-6 months for the ChAdOx1-S. Effectiveness against hospitalization and deaths declined by about 15% and 10%, respectively, during the first 6-8 months. Boosters (third dose) returned the protection to the levels observed shortly after dose 2. In unvaccinated, previously infected individuals the protection against infection declined from 97% after 2 months to 72% at 18 months. Our results confirm the waning of vaccination-induced immunity against infection and a smaller decline in the protection against hospitalization and death. Boosting restores the original vaccine effectiveness. Post-infection immunity also decreases over time.

8 June 2023 in European Urology Open Science
Verified
Journal Article
Open access
OMOndrej Majek
Ondrej Majek
MBMarek Babjuk
Marek Babjuk
MRMonique J. Roobol
Monique J. Roobol
OBOla Bratt
Ola Bratt
HPHendrik Van Poppel
Hendrik Van Poppel
VVVlastimil Válek
Vlastimil Válek
An updated Council of the EU recommendation on cancer screening was adopted in December 2022 during the Czech EU presidency. The recommendation included prostate cancer as a suitable target disease for organised screening, and invited countries to proceed with piloting and further research. To support further discussions and actions to promote early detection of prostate cancer, an international conference in November 2022 (Prostaforum 2022) resulted in a joint declaration. Here we describe the EU policy background, summarise the preparation of the declaration and the key underlying evidence and expert recommendations, and report the text of the declaration. The declaration summarises the striking inequalities in prostate cancer burden in Europe and calls on all stakeholders to consider and support concrete steps for advancement of organised early detection of prostate cancer. Our aim is to request endorsement of the text and potential initiation of practical actions by all stakeholders to support the aims of the declaration. Prostate cancer is among the most frequent cancers and is one of the most common causes of cancer death among men. The European Union has recommended new pilot programmes for prostate cancer screening. The Prostaforum 2022 declaration invites all stakeholders to support this new recommendation with specific steps.

10 May 2011 in BMC Public Health
Verified
Journal Article
Open access
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OMOndrej Majek
Ondrej Majek
JDJan Danes
Jan Danes
MSMiroslava Skovajsova
Miroslava Skovajsova
HBHelena Bartonkova
Helena Bartonkova
LBLucie Buresova
Lucie Buresova
LDLadislav Dušek
Ladislav Dušek
Background: The Czech Breast Cancer Screening Programme (CBCSP) was initiated in September 2002 by establishing a network of accredited centres. The aim of this article is to describe progress in the programme quality over time after the inception of the organised programme. Methods: The CBCSP is monitored using an information system consisting of three principal components: 1) the national cancer registry, 2) a screening registry collecting data on all screening examinations, further assessments and final diagnoses at accredited programme centres, and 3) administrative databases of healthcare payers. Key performance indicators from the European Guidelines have been adopted for continuous monitoring. Results: Breast cancer incidence in the Czech Republic has steadily been increasing, however with a growing proportion of less advanced stages. The mortality rate has recently stabilised. The screening registry includes 2,083,285 records on screening episodes between 2002 and 2008. In 2007-2008, 51% of eligible women aged 45-69 were screened. In 2008, the detection rates were 6.1 and 3.7 per 1,000 women in initial and subsequent screening respectively. Corresponding recall rates are 3.9% and 2.2%, however, it is necessary to pay attention to further assessment performed during the screening visits. Benign to malignant open biopsy ratio was 0.1. Of invasive cases detected in screening, 35.6% was less than 10 mm in diameter. Values of early performance indicators, as measured by both crude and standardized estimates, are generally improving and fulfil desirable targets set by European Guidelines. Conclusions: Mammography screening in the Czech Republic underwent successful transformation from opportunistic prevention to an organised programme. Values of early indicators confirm continuous improvement in different aspects of process quality. Further stimulation of participation through invitation system is necessary to exploit the full potential of screening mammography at the population level.

25 March 2014 in BMC Gastroenterology
Verified
Journal Article
Open access
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LSLubomir Slavicek
Lubomir Slavicek
TPTomas Pavlik
Tomas Pavlik
JTJiri Tomasek
Jiri Tomasek
ZBZbynek Bortlicek
Zbynek Bortlicek
TBTomas Buchler
Tomas Buchler
LDLadislav Dušek
Ladislav Dušek
Patients aged 65 years and older represent the majority of patients with metastatic colorectal cancer (mCRC). However, this patient population is often underrepresented in clinical trials and probably undertreated in the clinical practice.