Overlap of primary studies among systematic reviews (SRs) is one of the main methodological challenges when conducting overviews. If not assessed properly, overlapped primary studies may mislead findings, since they may have a major influence either in qualitative analyses or in statistical weight. Moreover, overlapping SRs may represent the existence of duplicated efforts. Matrices of evidence and the calculation of the overall corrected covered area (CCA) are appropriate methods to address this issue, but they seem to be not comprehensive enough. In this article we present Graphical Representation of Overlap for

Introduction: Evidence about COVID-19 and pregnancy has rapidly increased since December 2019, making it difficult to make rigorous evidence-based decisions. The objective of this overview of systematic reviews is to conduct a comprehensive analysis of the current evidence on prognosis of COVID-19 in pregnant women. Material and methods: We used Living OVerview of Evidence (L•OVE) platform for COVID-19, which continually retrieves studies from 46 data sources (including Pubmed/MEDLINE, Embase, other electronic databases, clinical trials registries, preprint repositories, among other sources relevant to COVID-19), mapping them into PICO questions. The search covered the period from the inception date of each database to September 13, 2020. We included systematic reviews assessing outcomes of pregnant women with COVID-19 and/or their newborns. Two authors independently screened the titles and abstracts, assessed full-texts to select the studies that met the inclusion criteria, extracted data, and appraised the risk of bias of each included systematic review. We measured the overlap of primary studies included among the selected systematic reviews by building a matrix of evidence, calculating the corrected covered area, and assessing the level of overlapping for every pair of systematic reviews. Results: Our search yielded 1132 references. 52 systematic reviews met inclusion criteria and were included in this overview. Only one review had a low risk of bias, three had an unclear risk of bias, and 48 had a high risk of bias. Most of the included reviews were highly overlapped among each other. In the included reviews, rates of maternal death varied from 0% to 11.1%, admission to intensive care from 2.1% to 28.5%, preterm deliveries before 37 weeks from 14.3% to 61.2%, and cesarean delivery from 48.3% to 100%. Regarding neonatal outcomes, neonatal death varied from 0% to 11.7% while the estimated infection status of the newborn varied between 0% and 11.5%. Conclusions: Only one of 52 systematic reviews had a low risk of bias. Results were heterogenous and the overlap of primary studies was frequently very high between pairs of systematic reviews. High quality evidence syntheses of comparative studies are needed to guide future clinical decisions.

Background Breast cancer (BC) clinical guidelines offer evidence-based recommendations to improve quality of healthcare for patients with or at risk of BC. Suboptimal adherence to recommendations has the potential to negatively affect population health. However, no study has systematically reviewed the impact of BC guideline adherence -as prognosis factor- on BC healthcare processes and health outcomes. The objectives are to analyse the impact of guideline adherence on health outcomes and on healthcare costs. Methods We searched systematic reviews and primary studies in MEDLINE and Embase, conducted in European Union (EU) countries (inception to May 2019). Eligibility assessment, data extraction, and risk of bias assessment were conducted by one author and crosschecked by a second. We used random-effects meta-analyses to examine the impact of guideline adherence on overall survival and disease-free survival, and assessed certainty of evidence using GRADE. Results We included 21 primary studies. Most were published during the last decade (90%), followed a retrospective cohort design (86%), focused on treatment guideline adherence (95%), and were at low (80%) or moderate (20%) risk of bias. Nineteen studies (95%) examined the impact of guideline adherence on health outcomes, while two (10%) on healthcare cost. Adherence to guidelines was associated with increased overall survival (HR = 0.67, 95%CI 0.59–0.76) and disease-free survival (HR = 0.35, 95%CI 0.15–0.82), representing 138 more survivors (96 more to 178 more) and 336 patients free of recurrence (73 more to 491 more) for every 1000 women receiving adherent CG treatment compared to those receiving non-adherent treatment at 5 years follow-up (moderate certainty). Adherence to treatment guidelines was associated with higher costs, but adherence to follow-up guidelines was associated with lower costs (low certainty). Conclusions Our review of EU studies suggests that there is moderate certainty that adherence to BC guidelines is associated with an improved survival. BC guidelines should be rigorously implemented in the clinical setting. Trial registration PROSPERO (CRD42018092884).

Background Self-management (SM) interventions are supportive interventions systematically provided by healthcare professionals, peers, or laypersons to increase the skills and confidence of patients in their ability to manage chronic diseases. We had two objectives: (1) to summarise the preferences and experiences of patients and their caregivers (informal caregivers and healthcare professionals) with SM in four chronic diseases and (2) to identify and describe the relevant outcomes for SM interventions from these perspectives. Methods We conducted a mixed-methods scoping review of reviews. We searched three databases until December 2020 for quantitative, qualitative, or mixed-methods reviews exploring patients' and caregivers' preferences or experiences with SM in type 2 diabetes mellitus (T2DM), obesity, chronic obstructive pulmonary disease (COPD), and heart failure (HF). Quantitative data were narratively synthesised, and qualitative data followed a three-step descriptive thematic synthesis. Identified themes were categorised into outcomes or modifiable factors of SM interventions. Results We included 148 reviews covering T2DM (n = 53 [35.8%]), obesity (n = 20 [13.5%]), COPD (n = 32 [21.6%]), HF (n = 38 [25.7%]), and those with more than one disease (n = 5 [3.4%]). We identified 12 main themes. Eight described the process of SM (disease progression, SM behaviours, social support, interaction with healthcare professionals, access to healthcare, costs for patients, culturally defined roles and perceptions, and health knowledge), and four described their experiences with SM interventions (the perceived benefit of the intervention, individualised care, sense of community with peers, and usability of equipment). Most themes and subthemes were categorised as outcomes of SM interventions. Conclusion The process of SM shaped the perspectives of patients and their caregivers on SM interventions. Their perspectives were influenced by the perceived benefit of the intervention, the sense of community with peers, the intervention's usability, and the level of individualised care. Our findings can inform the selection of patient-important outcomes, decisionmaking processes, including the formulation of recommendations, and the design and implementation of SM interventions.