Assessment of a venous thromboembolism prophylaxis shared decision-making intervention (DASH-TOP) using the decisional conflict scale: a mixed-method study.

BACKGROUND: Venous thromboembolism (VTE) in pregnancy is a major cause of maternal morbidity and death. The use of low-molecular-weight heparin (LMWH), despite being the standard of care to prevent VTE, comes with some challenges. Shared decision-making (SDM) interventions are recommended to support patients and clinicians in making preference-sensitive decisions. The quality of the SDM process has been widely assessed with the decisional conflict scale (DCS). Our aim is to report participants' perspectives of each of the components of an SDM intervention (DASH-TOP) in relation to the different subscales of the DCS. METHODS: Design: A convergent, parallel, mixed-methods design. PARTICIPANTS: The sample consisted of 22 health care professionals, students of an Applied Clinical Research in Health Sciences (ICACS) master program. INTERVENTION: We randomly divided the participants in three groups: Group 1 received one component (evidence -based information), Group 2 received two components (first component and value elicitation exercises), and Group 3 received all three components (the first two and a decision analysis recommendation) of the SDM intervention. ANALYSIS: For the quantitative strand, we used a non-parametric test to analyze the differences in the DCS subscales between the three groups. For the qualitative strand, we conducted a content analysis using the decisional conflict domains to deductively categorize the responses. RESULTS: Groups that received more intervention components experienced less conflict and better decision-making quality, although the differences between groups were not statistically significant. The decision analysis recommendation improved the efficacy with the decision-making process, however there are some challenges when implementing it in clinical practice. The uncertainty subscale showed a high decisional conflict for all three groups; contributing factors included low certainty of the evidence-based information provided and a perceived small effect of the drug to reduce the risk of a VTE event. CONCLUSIONS: The DASH-TOP intervention reduced decisional conflict in the decision -making process, with decision analysis being the most effective component to improve the quality of the decision. There is a need for more implementation research to improve the delivery of SDM interventions in the clinical encounter.

Decision Analysis in SHared decision making for Thromboprophylaxis during Pregnancy (DASH-TOP): a sequential explanatory mixed-methods pilot study.

OBJECTIVES: To gain insight into formal methods of integrating patient preferences and clinical evidence to inform treatment decisions, we explored patients' experience with a personalised decision analysis intervention, for prophylactic low-molecular-weight heparin (LMWH) in the antenatal period. DESIGN: Mixed-methods explanatory sequential pilot study. SETTING: Hospitals in Canada (n=1) and Spain (n=4 sites). Due to the COVID-19 pandemic, we conducted part of the study virtually. PARTICIPANTS: 15 individuals with a prior venous thromboembolism who were pregnant or planning pregnancy and had been referred for counselling regarding LMWH. INTERVENTION: A shared decision-making intervention that included three components: (1) direct choice exercise; (2) preference elicitation exercises and (3) personalised decision analysis. MAIN OUTCOME MEASURES: Participants completed a self-administered questionnaire to evaluate decision quality (decisional conflict, self-efficacy and satisfaction). Semistructured interviews were then conducted to explore their experience and perceptions of the decision-making process. RESULTS: Participants in the study appreciated the opportunity to use an evidence-based decision support tool that considered their personal values and preferences and reported feeling more prepared for their consultation. However, there were mixed reactions to the standard gamble and personalised treatment recommendation. Some participants could not understand how to complete the standard gamble exercises, and others highlighted the need for more informative ways of presenting results of the decision analysis. CONCLUSION: Our results highlight the challenges and opportunities for those who wish to incorporate decision analysis to support shared decision-making for clinical decisions.

Sex-Related Differences in Patient Characteristics, Risk Factors, and Symptomatology in Older Adults with Pulmonary Embolism: Findings from the SERIOUS-PE Study.

Sex-specific factors are implicated in pulmonary embolism (PE) presentation in young patients, as indicated by increased risk in pregnancy. Whether sex differences exist in PE presentation, comorbidities, and symptomatology in older adults, the age group in which most PEs occur, remains unknown. We identified older adults (aged ≥65 years) with PE in a large international PE registry replete with information about relevant clinical characteristics (RIETE registry, 2001-2021). To provide national data from the United States, we assessed sex differences in clinical characteristics and risk factors of Medicare beneficiaries with PE (2001-2019). The majority of older adults with PE in RIETE (19,294/33,462, 57.7%) and in the Medicare database (551,492/948,823, 58.7%) were women. Compared with men, women with PE less frequently had atherosclerotic diseases, lung disease, cancer, or unprovoked PE, but more frequently had varicose veins, depression, prolonged immobility, or history of hormonal therapy (p < 0.001 for all). Women less often presented with chest pain (37.3 vs. 40.6%) or hemoptysis (2.4 vs. 5.6%) but more often with dyspnea (84.6 vs. 80.9%) (p < 0.001 for all). Measures of clot burden, PE risk stratification, and use of imaging modalities were comparable between women and men. PE is more common in elderly women than in men. Cancer and cardiovascular disease are more common in men, whereas transient provoking factors including trauma, immobility, or hormone therapy are more common in elderly women with PE. Whether such differences correlate with disparities in treatment or differences in short- or long-term clinical outcomes warrants further investigation.

Sex Differences in PrEsentation, Risk Factors, Drug and Interventional Therapies, and OUtcomes of Elderly PatientS with Pulmonary Embolism: Rationale and design of the SERIOUS-PE study.

BACKGROUND: Sex is an important factor associated with pulmonary embolism (PE) disease presentation and outcomes, which may be related to pathobiological, social, and treatment-based differences. We are seeking to illuminate sex differences in pulmonary embolism presentation, care, and outcomes using an international registry and a national US database of people 65 years and older, the age group in which the majority of these events occur. METHODS: The Sex Differences in PrEsentation, Risk Factors, Drug and Interventional Therapies, and OUtcomes of Elderly PatientS with Pulmonary Embolism (SERIOUS-PE) study has been designed to address knowledge gaps in this area. This study will use data from the Registro Informatizado Enfermedad TromboEmbolica (RIETE) registry and the US Medicare Fee-For-Service beneficiaries. RIETE is a large international registry of patients with venous thromboembolism with data collected on PE presentation, risk factors, co-morbidities, drug and interventional therapies, as well as 30-day and 1-year outcomes (including recurrent VTE, major bleeding, and mortality). Data from US Medicare Fee-For-Service beneficiaries will be used to understand the sex differences in PE hospitalizations, advanced therapies, and outcomes at 30-day and 1-year follow-up. Assessment of outcomes in both databases will be performed in unadjusted models, as well as those adjusted for demographics, co-morbidities, and treatments, to understand whether the potential sex differences in outcomes are related to differences in risk factors and co-morbidities, potential disparities in treatment, or a plausible biological difference in women versus men. Linear trends will be assessed over time. RESULTS: RIETE data from March 2001 through March 2021 include 33,462 elderly patients with PE, of whom 19,294 (57.7%) were women and 14,168 (42.3%) were men. In the Medicare Fee-For-Service database, between January 2001 and December 31, 2019, 1,030,247 patients were hospitalized with a principal discharge diagnosis of PE, of whom 599,816 (58.2%) were women and 430,431 (41.8%) were men. CONCLUSIONS: Findings from the SERIOUS-PE study will help address important knowledge gaps related to sex differences in presentation and risk factors, treatment patterns, and outcomes of older adults with PE. The results may guide changes in prognostic prediction rules based on sex-specific findings, identify sex-based disparities in care delivery that should be addressed by quality improvement, or uncover potential differences in response to available therapies that warrant testing in dedicated randomized trials.

More work needed on decision analysis for shared decision-making: A scoping review.

OBJECTIVE: To explore and characterize published evidence on the ways decision analysis has been used to inform shared decision-making. STUDY DESIGN AND SETTING: For this scoping review, we searched five bibliographic databases (from inception until February 2021), reference lists of included studies, trial registries, a thesis database and websites of relevant interest groups. Studies were eligible if they evaluated the application of decision analysis in a shared decision-making encounter. Pairs of reviewers independently screened and selected studies for inclusion, extracted study information using a data extraction form developed by the research team and assessed risk of bias for all studies with an experimental or quasi-experimental design. Data were narratively synthesized. RESULTS: We identified 27 studies that varied greatly with regard to their patient population, design, content and delivery. A range of outcomes were evaluated to explore the effectiveness and acceptability of decision analytic interventions, with little information about the implementation process. Most studies found that decision analysis was broadly beneficial. CONCLUSION: Despite the compelling rationale on the potential for decision analysis to support shared decision-making, rigorous randomized controlled trials are needed to confirm these interventions' effectiveness, while qualitative studies should seek to understand their potential implementation.

Women's values and preferences for thromboprophylaxis during pregnancy: a comparison of direct-choice and decision analysis using patient specific utilities.

BACKGROUND: Women with a history of venous thromboembolism (VTE) have an increased recurrence risk during pregnancy. Low molecular weight heparin (LMWH) reduces this risk, but is costly, burdensome, and may increase risk of bleeding. The decision to start thromboprophylaxis during pregnancy is sensitive to women's values and preferences. Our objective was to compare women's choices using a holistic approach in which they were presented all of the relevant information (direct-choice) versus a personalized decision analysis in which a mathematical model incorporated their preferences and VTE risk to make a treatment recommendation. METHODS: Multicenter, international study. Structured interviews were on women with a history of VTE who were pregnant, planning, or considering pregnancy. Women indicated their willingness to receive thromboprophylaxis based on scenarios using personalized estimates of VTE recurrence and bleeding risks. We also obtained women's values for health outcomes using a visual analog scale. We performed individualized decision analyses for each participant and compared model recommendations to decisions made when presented with the direct-choice exercise. RESULTS: Of the 123 women in the study, the decision model recommended LMWH for 51 women and recommended against LMWH for 72 women. 12% (6/51) of women for whom the decision model recommended thromboprophylaxis chose not to take LMWH; 72% (52/72) of women for whom the decision model recommended against thromboprophylaxis chose LMWH. CONCLUSIONS: We observed a high degree of discordance between decisions in the direct-choice exercise and decision model recommendations. Although which approach best captures individuals' true values remains uncertain, personalized decision support tools presenting results based on personalized risks and values may improve decision making.

Evaluating patient values and preferences for thromboprophylaxis decision making during pregnancy: a study protocol.

BACKGROUND: Pregnant women with prior venous thromboembolism (VTE) are at risk of recurrence. Low molecular weight heparin (LWMH) reduces the risk of pregnancy-related VTE. LMWH prophylaxis is, however, inconvenient, uncomfortable, costly, medicalizes pregnancy, and may be associated with increased risks of obstetrical bleeding. Further, there is uncertainty in the estimates of both the baseline risk of pregnancy-related recurrent VTE and the effects of antepartum LMWH prophylaxis. The values and treatment preferences of pregnant women, crucial when making recommendations for prophylaxis, are currently unknown. The objective of this study is to address this gap in knowledge. METHODS: We will perform a multi-center cross-sectional interview study in Canada, USA, Norway and Finland. The study population will consist of 100 women with a history of lower extremity deep vein thrombosis (DVT) or pulmonary embolism (PE), and who are either pregnant, planning pregnancy, or may in the future consider pregnancy (women between 18 and 45 years). We will exclude individuals who are on full dose anticoagulation or thromboprophylaxis, who have undergone surgical sterilization, or whose partners have undergone vasectomy. We will determine each participant's willingness to receive LMWH prophylaxis during pregnancy through direct choice exercises based on real life and hypothetical scenarios, preference-elicitation using a visual analog scale ("feeling thermometer"), and a probability trade-off exercise. The primary outcome will be the minimum reduction (threshold) in VTE risk at which women change from declining to accepting LMWH prophylaxis. We will explore possible determinants of this choice, including educational attainment, the characteristics of the women's prior VTE, and prior experience with LMWH. We will determine the utilities that women place on the burden of LMWH prophylaxis, pregnancy-related DVT, pregnancy-related PE and pregnancy-related hemorrhage. We will generate a "personalized decision analysis" using participants' utilities and their personalized risk of recurrent VTE as inputs to a decision analytic model. We will compare the personalized decision analysis to the participant's stated choice. DISCUSSION: The preferences of pregnant women at risk of VTE with respect to the use of antithrombotic therapy remain unexplored. This research will provide explicit, quantitative expressions of women's valuations of health states related to recurrent VTE and its prevention with LMWH. This information will be crucial for both guideline developers and for clinicians.

2009 evidence-based clinical practice guidelines for diagnosing a first episode of lower extremities deep vein thrombosis in ambulatory outpatients.

INTRODUCTION: The GRADE working group has recently suggested a rigorous framework for clinical practice guidelines (CPG) addressing diagnostic tests and test strategies based on the impact of alternative approaches on patient-important outcomes. The framework mandates explicit evidence summaries, ratings of the quality of evidence, and specifying recommendations as strong or weak. OBJECTIVES: To test the feasibility and performance of the GRADE approach, we applied this framework to well-researched issues in the diagnoses of deep venous thrombosis (DVT). METHODS: A 16-member panel with interest in thromboembolism and CPG development identified pertinent clinical questions. Our search for relevant studies included existing CPG and systematic reviews. We summarized the data in form of evidence tables and developed recommendations including, when needed, a formal consensus process. RESULTS AND CONCLUSIONS: We provide three groups of recommendations for clinicians practicing in settings with access to different types of D-dimer tests -- highly sensitive, moderately sensitive, and no availability of D-dimer. We consider the use of clinical prediction rules in guiding the diagnostic process, the potential for negative D-dimer or venous ultrasound (US) to rule out disease, and the role of follow-up testing (US following positive D-dimer result, D-dimer following negative US, and serial US) depending on the probability of DVT at the start of diagnostic process. We recommend the following: that clinicians without access to a highly or moderately sensitive D-dimer test rely on US to guide DVT diagnosis; that those with access use the highly sensitive D-dimer to determine, in patients with low or moderate probability of DVT (by the Wells rule) whether US is needed; that in patients with low pre-test probability (pre-TP) and a negative D-dimer (either highly or moderately sensitive) they follow patients without further testing; that in patients with high pre-test probability they perform a compression ultrasound without D-dimer testing.

Human-derived D-dimer for external quality assessment: results of four surveys in Ontario.

External quality assessment (EQA) of D-dimer assays has been limited by a lack of standardized human-derived testing material. In 2006 and 2007, the Quality Management Program--Laboratory Services, Toronto, Canada, investigated the use of commercially prepared lyophilized human plasma spiked with human-derived D-dimer components manufactured by Affinity Biologicals, Hamilton, Canada. Four surveys were performed. Participants reported the level or presence of D-dimer using quantitative or qualitative methods. Participants performing quantitative testing provided their unit of measure and reference interval. Results were considered correct if they fell within the range appropriate for each sample (normal/negative or abnormal/positive). Overall, survey results were excellent, with 4.0% (95% confidence interval [CI], 1.3%-9.1%), 0.8% (CI, 0.0%-1.5%), 2.3% (CI, 0.5%-6.6%), and 2.3% (CI, 0.4%-6.6%) of participants reporting an incorrect result in the first, second, third, and fourth surveys, respectively. A commercially prepared D-dimer is a suitable material for EQA testing.

Accuracy and usefulness of a clinical prediction rule and D-dimer testing in excluding deep vein thrombosis in cancer patients.

INTRODUCTION: Deep vein thrombosis (DVT) can be safely and reliably excluded in patients with a low clinical probability and a negative D-dimer result but the accuracy and utility of such a strategy is less certain in cancer patients. We sought to compare the performance of the Wells pretest probability (PTP) model and D-dimer testing between patients with and without cancer and to examine the utility of the two PTP model classification schemes (low/moderate/high versus unlikely/likely) in excluding DVT in patients with cancer. MATERIALS AND METHODS: Pooled analysis of databases from three prospective diagnostic studies evaluating consecutive outpatients with suspected DVT. RESULTS: A total of 2696 patients were evaluated. DVT was diagnosed in 403 (15%) patients overall and in 83 of 200 (41.5%) cancer patients. The PTP distribution and the prevalence of DVT in each PTP category were significantly different between patients with and without cancer, regardless of the classification used (p<0.01). In patients with cancer, the negative predictive values of a low or unlikely PTP score in combination with a negative D-dimer result were 100% (95% CI 69.8%-100%) and 100% (95% CI 82.8%-96.6%), respectively. However, the specificities ranged from 46.2% (95%CI 27.1%-66.3%) to 57.1% (95%CI 41.1%-71.9%). Further testing was required in 94% of cancer patients using the low/moderate/high PTP classification and in 88% using the unlikely/likely stratification. CONCLUSIONS: As in patients without cancer, the combination of a low or unlikely PTP with a negative D-dimer result can exclude DVT in patients with cancer. However, this strategy has limited utility because very few cancer patients present with this combination.