Zuleika Saz-Parkinson
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Zuleika Saz-Parkinson has a total of 240 co-authors. Here are the top co-authors by number of shared publications:
- Holger Jens Schünemann
Clinical Epidemiology and Research Center (CERC), Humanitas University & Humanitas Research Hospital, Milan, Italy
8 shared publications Elena Parmelli
European Commission Joint Research Centre, Ispra, Italy (E.P., Z.S.-P.)
7 shared publications- Pablo Alonso-Coello
Centre for Biomedical Research in Epidemiology and Public Health (CIBERESP) Madrid Spain
7 shared publications - Thomas Piggott
Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada; Peterborough Public Health, Peterborough, Ontario, Canada; Department of Family Medicine, Queens University, Kingston, Ontario, Canada
7 shared publications - Miranda W. Langendam
Department of Epidemiology and Data Science, Amsterdam UMC location VUmc, Amsterdam, the Netherlands
6 shared publications - Paolo Giorgi Rossi
Epidemiology Unit, AUSL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
5 shared publications
Latest Publications
- Top Cited Papers
- 1 March 2026
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 179 (3) , 430-439
GRADE Guidance: Update on Developing Good Practice Statements in Guidelines
Despite published guidance by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) Working Group on the use of good practice statements (GPSs), their appropriate development remains challenging. This article provides updated guidance with nuanced operationalization. The updated guidance was developed on the basis of examples and iterative discussions. The lead authors refined the approach according to the feedback from GRADE Working Group meetings and presented the summary of the results to all attendees of the GRADE Working Group meeting for feedback in September 2023 and for final approval in September 2024. The 5 signaling questions from the original guidance were leveraged, and the authors recommend that guideline developers select relevant Evidence to Decision criteria to assess the potential downstream consequences of implementing the statement. They have updated the definition of a GPS, classifying GPSs into the following 3 categories: those grounded in ethics and human rights; those grounded in essential principles, practices, and protocols; and those grounded in established scientific evidence. Practical examples accompany the steps as they relate to each type of GPS. In addition, the authors introduce a tool to streamline GPS development and enhance the reporting process. This GRADE guidance article provides an update on when and how to develop a GPS. Adherence to the guidance will add to the trustworthiness of guidelines and may facilitate reducing the inappropriate use or overuse of the GPS.
- 1 March 2026
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 179 (3) , 430-439
Top Cited PapersGRADE Guidance: Update on Developing Good Practice Statements in Guidelines
Despite published guidance by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) Working Group on the use of good practice statements (GPSs), their appropriate development remains challenging. This article provides updated guidance with nuanced operationalization. The updated guidance was developed on the basis of examples and iterative discussions. The lead authors refined the approach according to the feedback from GRADE Working Group meetings and presented the summary of the results to all attendees of the GRADE Working Group meeting for feedback in September 2023 and for final approval in September 2024. The 5 signaling questions from the original guidance were leveraged, and the authors recommend that guideline developers select relevant Evidence to Decision criteria to assess the potential downstream consequences of implementing the statement. They have updated the definition of a GPS, classifying GPSs into the following 3 categories: those grounded in ethics and human rights; those grounded in essential principles, practices, and protocols; and those grounded in established scientific evidence. Practical examples accompany the steps as they relate to each type of GPS. In addition, the authors introduce a tool to streamline GPS development and enhance the reporting process. This GRADE guidance article provides an update on when and how to develop a GPS. Adherence to the guidance will add to the trustworthiness of guidelines and may facilitate reducing the inappropriate use or overuse of the GPS.
- 1 November 2025
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 178 (11) , 1644-1652
GRADE Guidance: Using Thresholds for Judgments on Health Benefits and Harms in Decision Making (GRADE Guidance 42)
Users of GRADE (Grading of Recommendations Assessment, Development and Evaluation) make judgments about the size of intervention effects on desirable and undesirable people-important health outcomes or on benefits and harms. Benchmarking effect sizes by using decision thresholds (DTs) can help to facilitate these judgments and the process. This article provides GRADE guidance for use of DTs for judgments about the magnitude of desirable and undesirable health effects, such as in a health guideline or health technology assessment. Through iterative discussions and refinement in in-person and online meetings of a GRADE project group and through e-mail communication, the authors developed guidance for using DTs in Evidence-to-Decision (EtD) frameworks. The authors applied the approach and used these examples from guidelines and the results of a randomized methodological study to develop official GRADE guidance. Several alternatives for determining and using DTs are presented. In the first main approach, outcome-specific DTs for trivial, small, moderate, and large effects are determined through a calculation using empirically derived generic coefficients and the outcome's utility value and are compared with the effect estimate obtained from an evidence synthesis. In the second main approach, outcome-specific DTs are also determined, but through direct surveying of decision makers to explicitly assign thresholds for the prioritized health outcomes. The article also describes how these approaches can be combined. The suggested approaches provide transparency for judgments in EtD frameworks that are based on findings from evidence syntheses.
- 1 November 2025
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 178 (11) , 1644-1652
GRADE Guidance: Using Thresholds for Judgments on Health Benefits and Harms in Decision Making (GRADE Guidance 42)
Users of GRADE (Grading of Recommendations Assessment, Development and Evaluation) make judgments about the size of intervention effects on desirable and undesirable people-important health outcomes or on benefits and harms. Benchmarking effect sizes by using decision thresholds (DTs) can help to facilitate these judgments and the process. This article provides GRADE guidance for use of DTs for judgments about the magnitude of desirable and undesirable health effects, such as in a health guideline or health technology assessment. Through iterative discussions and refinement in in-person and online meetings of a GRADE project group and through e-mail communication, the authors developed guidance for using DTs in Evidence-to-Decision (EtD) frameworks. The authors applied the approach and used these examples from guidelines and the results of a randomized methodological study to develop official GRADE guidance. Several alternatives for determining and using DTs are presented. In the first main approach, outcome-specific DTs for trivial, small, moderate, and large effects are determined through a calculation using empirically derived generic coefficients and the outcome's utility value and are compared with the effect estimate obtained from an evidence synthesis. In the second main approach, outcome-specific DTs are also determined, but through direct surveying of decision makers to explicitly assign thresholds for the prioritized health outcomes. The article also describes how these approaches can be combined. The suggested approaches provide transparency for judgments in EtD frameworks that are based on findings from evidence syntheses.
- 1 May 2022
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 175 (5) , 735-739
Integrating Quality Assurance and Quality Improvement With Guidelines: Systematic Stakeholder-Driven Development of an Extension of the Guidelines International Network–McMaster Guideline Development Checklist
Frameworks and tools can help integrate development of clinical practice guidelines and tools for quality assurance and improvement. This article describes the Guidelines International Network–McMa...
- 1 May 2022
- Published by American College of Physicians in Annals of Internal Medicine
- Vol. 175 (5) , 735-739
Integrating Quality Assurance and Quality Improvement With Guidelines: Systematic Stakeholder-Driven Development of an Extension of the Guidelines International Network–McMaster Guideline Development Checklist
Frameworks and tools can help integrate development of clinical practice guidelines and tools for quality assurance and improvement. This article describes the Guidelines International Network–McMa...
- Open Access
- 15 April 2022
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 154, 197-203
The GIN-McMaster guideline tool extension for the integration of quality improvement and quality assurance in guidelines: a description of the methods for its development
- 15 April 2022
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 154, 197-203
Open AccessThe GIN-McMaster guideline tool extension for the integration of quality improvement and quality assurance in guidelines: a description of the methods for its development
- 1 January 2022
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 141, 161-171
A taxonomy and framework for identifying and developing actionable statements in guidelines suggests avoiding informal recommendations
- 1 January 2022
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 141, 161-171
A taxonomy and framework for identifying and developing actionable statements in guidelines suggests avoiding informal recommendations
- Open Access
- 26 November 2021
- Published by Springer Nature in British Journal of Cancer
- Vol. 126 (4) , 673-688
Benefits and harms of annual, biennial, or triennial breast cancer mammography screening for women at average risk of breast cancer: a systematic review for the European Commission Initiative on Breast Cancer (ECIBC)
Background: Although mammography screening is recommended in most European countries, the balance between the benefits and harms of different screening intervals is still a matter of debate. This review informed the European Commission Initiative on Breast Cancer (BC) recommendations. Methods: We searched PubMed, EMBASE, and the Cochrane Library to identify RCTs, observational or modelling studies, comparing desirable (BC deaths averted, QALYs, BC stage, interval cancer) and undesirable (overdiagnosis, false positive related, radiation related) effects from annual, biennial, or triennial mammography screening in women of average risk for BC. We assessed the certainty of the evidence using the GRADE approach. Results: We included one RCT, 13 observational, and 11 modelling studies. In women 50–69, annual compared to biennial screening may have small additional benefits but an important increase in false positive results; triennial compared to biennial screening may have smaller benefits while avoiding some harms. In younger women (aged 45–49), annual compared to biennial screening had a smaller gain in benefits and larger harms, showing a less favourable balance in this age group than in women 50–69. In women 70–74, there were fewer additional harms and similar benefits with shorter screening intervals. The overall certainty of the evidence for each of these comparisons was very low. Conclusions: In women of average BC risk, screening intervals have different trade-offs for each age group. The balance probably favours biennial screening in women 50–69. In younger women, annual screening may have a less favourable balance, while in women aged 70–74 years longer screening intervals may be more favourable.
- 26 November 2021
- Published by Springer Nature in British Journal of Cancer
- Vol. 126 (4) , 673-688
Open AccessBenefits and harms of annual, biennial, or triennial breast cancer mammography screening for women at average risk of breast cancer: a systematic review for the European Commission Initiative on Breast Cancer (ECIBC)
Background: Although mammography screening is recommended in most European countries, the balance between the benefits and harms of different screening intervals is still a matter of debate. This review informed the European Commission Initiative on Breast Cancer (BC) recommendations. Methods: We searched PubMed, EMBASE, and the Cochrane Library to identify RCTs, observational or modelling studies, comparing desirable (BC deaths averted, QALYs, BC stage, interval cancer) and undesirable (overdiagnosis, false positive related, radiation related) effects from annual, biennial, or triennial mammography screening in women of average risk for BC. We assessed the certainty of the evidence using the GRADE approach. Results: We included one RCT, 13 observational, and 11 modelling studies. In women 50–69, annual compared to biennial screening may have small additional benefits but an important increase in false positive results; triennial compared to biennial screening may have smaller benefits while avoiding some harms. In younger women (aged 45–49), annual compared to biennial screening had a smaller gain in benefits and larger harms, showing a less favourable balance in this age group than in women 50–69. In women 70–74, there were fewer additional harms and similar benefits with shorter screening intervals. The overall certainty of the evidence for each of these comparisons was very low. Conclusions: In women of average BC risk, screening intervals have different trade-offs for each age group. The balance probably favours biennial screening in women 50–69. In younger women, annual screening may have a less favourable balance, while in women aged 70–74 years longer screening intervals may be more favourable.
- Open Access
- 1 July 2021
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 135, 42-53
Challenges in applying the GRADE approach in public health guidelines and systematic reviews: a concept article from the GRADE Public Health Group
- 1 July 2021
- Published by Elsevier in Journal of Clinical Epidemiology
- Vol. 135, 42-53
Open AccessChallenges in applying the GRADE approach in public health guidelines and systematic reviews: a concept article from the GRADE Public Health Group
- Open Access
- 13 May 2021
- Published by Springer Nature in Health Research Policy and Systems
- Vol. 19 (1) , 1-9
Contextual differences considered in the Tunisian ADOLOPMENT of the European guidelines on breast cancer screening
Background: Breast cancer is a common disease in Tunisia and is associated with high mortality rates. The “Instance Nationale de l’Evaluation et de l’Accréditation en Santé” (INEAS) and the Tunisian Society of Oncology decided to develop practice guidelines on the subject. While the development of de novo guidelines on breast cancer screening is a demanding process, guideline adaptation appears more appropriate and context sensitive. The objective of this paper is to describe the adaptation process of the European Guidelines on Breast Cancer Screening and Diagnosis to the Tunisian setting in terms of the methodological process, contextual differences between the source and adoloped guideline, and changes in the recommendations. Methods: We used the ‘Grading of Recommendations Assessment, Development and Evaluation’ (GRADE)-ADOLOPMENT methodology to prioritize the topic, select the source guideline, and prioritize the questions and the outcomes. Once the source guideline was selected—the European Breast Cancer Guidelines—the European Commission´s Joint Research Centre shared with the project team in Tunisia all relevant documents and files. In parallel, the project team searched for local studies on the disease prevalence, associated outcomes’ baseline risks, patients’ values and preferences, cost, cost-effectiveness, acceptability, and feasibility. Then, the adoloping panel reviewed the GRADE evidence tables and the Evidence to Decision tables and discussed whether their own judgments were consistent with those from the source guideline or not. They based their judgments on the evidence on health effects, the contextual evidence, and their own experiences. Results: The most relevant contextual differences between the source and adoloped guidelines were related to the perspective, scope, prioritized questions, rating of outcome importance, baseline risks, and indirectness of the evidence. The ADOLOPMENT process resulted in keeping 5 out of 6 recommendations unmodified. One recommendation addressing “screening versus no screening with ultrasound in women with high breast density on mammography screening” was modified from ‘conditional against’ to ‘conditional for either’ due to more favorable ratings by the adoloping panel in terms of equity and feasibility. Conclusion: This process illustrates both the feasibility of GRADE-ADOLOPMENT approach and the importance of consideration of contextual evidence. It also highlights the value of collaboration with the organization that developed the source guideline.
- 13 May 2021
- Published by Springer Nature in Health Research Policy and Systems
- Vol. 19 (1) , 1-9
Open AccessContextual differences considered in the Tunisian ADOLOPMENT of the European guidelines on breast cancer screening
Background: Breast cancer is a common disease in Tunisia and is associated with high mortality rates. The “Instance Nationale de l’Evaluation et de l’Accréditation en Santé” (INEAS) and the Tunisian Society of Oncology decided to develop practice guidelines on the subject. While the development of de novo guidelines on breast cancer screening is a demanding process, guideline adaptation appears more appropriate and context sensitive. The objective of this paper is to describe the adaptation process of the European Guidelines on Breast Cancer Screening and Diagnosis to the Tunisian setting in terms of the methodological process, contextual differences between the source and adoloped guideline, and changes in the recommendations. Methods: We used the ‘Grading of Recommendations Assessment, Development and Evaluation’ (GRADE)-ADOLOPMENT methodology to prioritize the topic, select the source guideline, and prioritize the questions and the outcomes. Once the source guideline was selected—the European Breast Cancer Guidelines—the European Commission´s Joint Research Centre shared with the project team in Tunisia all relevant documents and files. In parallel, the project team searched for local studies on the disease prevalence, associated outcomes’ baseline risks, patients’ values and preferences, cost, cost-effectiveness, acceptability, and feasibility. Then, the adoloping panel reviewed the GRADE evidence tables and the Evidence to Decision tables and discussed whether their own judgments were consistent with those from the source guideline or not. They based their judgments on the evidence on health effects, the contextual evidence, and their own experiences. Results: The most relevant contextual differences between the source and adoloped guidelines were related to the perspective, scope, prioritized questions, rating of outcome importance, baseline risks, and indirectness of the evidence. The ADOLOPMENT process resulted in keeping 5 out of 6 recommendations unmodified. One recommendation addressing “screening versus no screening with ultrasound in women with high breast density on mammography screening” was modified from ‘conditional against’ to ‘conditional for either’ due to more favorable ratings by the adoloping panel in terms of equity and feasibility. Conclusion: This process illustrates both the feasibility of GRADE-ADOLOPMENT approach and the importance of consideration of contextual evidence. It also highlights the value of collaboration with the organization that developed the source guideline.
- Open Access
- 5 March 2021
- Published by Wiley in Cancer Medicine
- Vol. 10 (7) , 2191-2204
Digital breast tomosynthesis compared to diagnostic mammographic projections (including magnification) among women recalled at screening mammography: a systematic review for the European Commission Initiative on Breast Cancer (ECIBC)
Background: Diagnostic mammography projections (DxMM) have been traditionally used in the assessment of women recalled after a suspicious screening mammogram. Digital breast tomosynthesis (DBT) reduces the tissue overlap effect, thus improving image assessment. Some studies have suggested DBT might replace DxMM with at least equivalent performance.Objective: To evaluate the replacement of DxMM with DBT in women recalled at screening.Methods: We searched PubMed, EMBASE, and the Cochrane Library databases to identify diagnostic paired cohort studies or RCTs comparing DBT vs DxMM, published in English that: reported accuracy outcomes, recruited women recalled for assessment at mammography screening, and included a reference standard. Subgroup analysis was performed over lesion characteristics. We provided pooled accuracy estimates and differences between tests using a quadrivariate model. We assessed the certainty of the evidence using the GRADE approach.Results: We included ten studies that reported specificity and sensitivity. One study included 7060 women while the remaining included between 52 and 738 women. DBT compared with DxMM showed a pooled difference for the sensitivity of 2% (95% CI 1%–3%) and a pooled difference for the specificity of 6% (95%CI 2%–11%). Restricting the analysis to the six studies that included women with microcalcification lesions gave similar results. In the context of a prevalence of 21% of breast cancer (BC) in recalled women, DBT probably detects 4 (95% CI 2–6) more BC cases and has 47 (95%CI 16–87) fewer false‐positive results per 1000 assessments. The certainty of the evidence was moderate due to risk of bias.Conclusion: The evidence in the assessment of screen‐recalled findings with DBT is sparse and of moderate certainty. DBT probably has higher sensitivity and specificity than DxMM. Women, health care providers and policymakers might value as relevant the reduction of false‐positive results and related fewer invasive diagnostic procedures with DBT, without missing BC cases.
- 5 March 2021
- Published by Wiley in Cancer Medicine
- Vol. 10 (7) , 2191-2204
Open AccessDigital breast tomosynthesis compared to diagnostic mammographic projections (including magnification) among women recalled at screening mammography: a systematic review for the European Commission Initiative on Breast Cancer (ECIBC)
Background: Diagnostic mammography projections (DxMM) have been traditionally used in the assessment of women recalled after a suspicious screening mammogram. Digital breast tomosynthesis (DBT) reduces the tissue overlap effect, thus improving image assessment. Some studies have suggested DBT might replace DxMM with at least equivalent performance.Objective: To evaluate the replacement of DxMM with DBT in women recalled at screening.Methods: We searched PubMed, EMBASE, and the Cochrane Library databases to identify diagnostic paired cohort studies or RCTs comparing DBT vs DxMM, published in English that: reported accuracy outcomes, recruited women recalled for assessment at mammography screening, and included a reference standard. Subgroup analysis was performed over lesion characteristics. We provided pooled accuracy estimates and differences between tests using a quadrivariate model. We assessed the certainty of the evidence using the GRADE approach.Results: We included ten studies that reported specificity and sensitivity. One study included 7060 women while the remaining included between 52 and 738 women. DBT compared with DxMM showed a pooled difference for the sensitivity of 2% (95% CI 1%–3%) and a pooled difference for the specificity of 6% (95%CI 2%–11%). Restricting the analysis to the six studies that included women with microcalcification lesions gave similar results. In the context of a prevalence of 21% of breast cancer (BC) in recalled women, DBT probably detects 4 (95% CI 2–6) more BC cases and has 47 (95%CI 16–87) fewer false‐positive results per 1000 assessments. The certainty of the evidence was moderate due to risk of bias.Conclusion: The evidence in the assessment of screen‐recalled findings with DBT is sparse and of moderate certainty. DBT probably has higher sensitivity and specificity than DxMM. Women, health care providers and policymakers might value as relevant the reduction of false‐positive results and related fewer invasive diagnostic procedures with DBT, without missing BC cases.