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For long flights, the cruise is the longest phase and where the largest amount of fuel is consumed. An in-cruise optimization method has been implemented to calculate the optimal trajectory that reduces the flight cost. A three-dimensional grid has been created, coupling lateral navigation and vertical navigation profiles. With a dynamic analysis of the wind, the aircraft can perform a horizontal deviation or change altitudes via step climbs to reduce fuel consumption. As the number of waypoints and possible step climbs is increased, the number of flight trajectories increases exponentially; thus, a genetic algorithm has been implemented to reduce the total number of calculated trajectories compared to an exhaustive search. The aircraft’s model has been obtained from a performance database, which is currently used in the commercial flight management system studied in this paper. A 5% average flight cost reduction has been obtained.
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Study Design. Prospective cohort study.Objective. The aim of this study was to identify treatment response trajectories in patients with low back pain (LBP) during and after multidisciplinary care in a tertiary spine center, and to examine baseline patient characteristics that can distinguish trajectories.Summary of Background Data. Treatment response is often heterogeneous between patients with LBP. Knowledge on key characteristics that are associated with courses of disability could identify patients at risk for less favorable outcome. This knowledge will help improve shared decision-making.Methods. Adult patients with LBP completed questionnaires on disability (Pain Disability Index) and LBP impact (Impact Stratification of the National Institutes of Health minimal dataset) at baseline, 6, 12, 18, and 24 months’ follow-up. Latent class analyses were applied to identify trajectories of disability and LBP impact. Baseline sociodemographic and clinical patient characteristics were compared between trajectory subgroups.Results. Follow-up was available for 996 patients on disability and 707 patients on LBP impact. Six trajectories were identified for both outcome measures. Three disability trajectories remained stable at distinct levels of severity (68% of patients) and three trajectories showed patterns of recovery (32%). For LBP impact there was one stable trajectory (17%), two slightly improving (59%), two recovering (15%), and one with a pattern of recovery and relapse (15%). Significant differences between trajectories were observed for almost all baseline patient characteristics.Conclusion. On average, patients show moderate improvements in disability and LBP impact 2 years after visiting a multidisciplinary tertiary spine center. However, latent class analyses revealed that most patients belong to subgroups experiencing stable levels of disability and LBP impact. Differences in baseline patient characteristics were mostly associated with baseline levels of functioning, instead of (un)favorable outcome during follow-up.
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BACKGROUND: Although the importance of evaluating implementation fidelity is acknowledged, little is known about heterogeneity in fidelity over time. This study aims to generate insight into the heterogeneity in implementation fidelity trajectories of a health promotion program in multidisciplinary settings and the relationship with changes in patients' health behavior.METHODS: This study used longitudinal data from the nationwide implementation of an evidence-informed physical activity promotion program in Dutch rehabilitation care. Fidelity scores were calculated based on annual surveys filled in by involved professionals (n = ± 70). Higher fidelity scores indicate a more complete implementation of the program's core components. A hierarchical cluster analysis was conducted on the implementation fidelity scores of 17 organizations at three different time points. Quantitative and qualitative data were used to explore organizational and professional differences between identified trajectories. Regression analyses were conducted to determine differences in patient outcomes.RESULTS: Three trajectories were identified as the following: 'stable high fidelity' (n = 9), 'moderate and improving fidelity' (n = 6), and 'unstable fidelity' (n = 2). The stable high fidelity organizations were generally smaller, started earlier, and implemented the program in a more structured way compared to moderate and improving fidelity organizations. At the implementation period's start and end, support from physicians and physiotherapists, professionals' appreciation, and program compatibility were rated more positively by professionals working in stable high fidelity organizations as compared to the moderate and improving fidelity organizations (p < .05). Qualitative data showed that the stable high fidelity organizations had often an explicit vision and strategy about the implementation of the program. Intriguingly, the trajectories were not associated with patients' self-reported physical activity outcomes (adjusted model β = - 651.6, t(613) = - 1032, p = .303).CONCLUSIONS: Differences in organizational-level implementation fidelity trajectories did not result in outcome differences at patient-level. This suggests that an effective implementation fidelity trajectory is contingent on the local organization's conditions. More specifically, achieving stable high implementation fidelity required the management of tensions: realizing a localized change vision, while safeguarding the program's standardized core components and engaging the scarce physicians throughout the process. When scaling up evidence-informed health promotion programs, we propose to tailor the management of implementation tensions to local organizations' starting position, size, and circumstances.TRIAL REGISTRATION: The Netherlands National Trial Register NTR3961 . Registered 18 April 2013.
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Introduction: The implementation of oncology care pathways that standardize organizational procedures has improved cancer care in recent years. However, the involvement of “authentic” patients and caregivers in quality improvement of these predetermined pathways is in its infancy, especially the scholarly reflection on this process. We, therefore, aim to explore the multidisciplinary challenges both in practice, when cancer patients, their caregivers, and a multidisciplinary team of professionals work together on quality improvement, as well as in our research team, in which a social scientist, health care professionals, health care researchers, and experience experts design a research project together. Methods and design: Experience-based co-design will be used to involve cancer patients and their caregivers in a qualitative research design. In-depth open discovery interviews with 12 colorectal cancer patients, 12 breast cancer patients, and seven patients with cancer-associated thrombosis and their caregivers, and focus group discussions with professionals from various disciplines will be conducted. During the subsequent prioritization events and various co-design quality improvement meetings, observational field notes will be made on the multidisciplinary challenges these participants face in the process of co-design, and evaluation interviews will be done afterwards. Similar data will be collected during the monthly meetings of our multidisciplinary research team. The data will be analyzed according to the constant comparative method. Discussion: This study may facilitate quality improvement programs in oncologic care pathways, by increasing our real-world knowledge about the challenges of involving “experience experts” together with a team of multidisciplinary professionals in the implementation process of quality improvement. Such co-creation might be challenging due to the traditional paternalistic relationship, actual disease-/treatment-related constraints, and a lack of shared language and culture between patients, caregivers, and professionals and between professionals from various disciplines. These challenges have to be met in order to establish equality, respect, team spirit, and eventual meaningful participation.
ObjectivesTo identify distinct sets of disability trajectories in the year before and after a Medicare qualifying skilled nursing facility (Q-SNF) admission, evaluate the associations between the pre–and post–Q-SNF disability trajectories, and determine short-term outcomes (readmission, mortality).Design, setting, and participantsProspective cohort study including 754 community-dwelling older persons, 70+ years, and initially nondisabled in their basic activities of daily living. The analytic sample included 394 persons, with a first hospitalization followed by a Q-SNF admission between 1998 and 2012.Main outcomes and measuresDisability in the year before and after a Q-SNF admission using 13 basic, instrumental, and mobility activities. Secondary outcomes included 30-day readmission and 12-month mortality.ResultsThe mean (SD) age of the sample was 84.9 (5.5) years. We identified 3 disability trajectories in the year before a Q-SNF admission: minimal disability (37.3% of participants), mild disability (44.6%), and moderate disability (18.2%). In the year after a Q-SNF admission, all participants started with moderate to severe disability scores. Three disability trajectories were identified: substantial improvement (26.0% of participants), minimal improvement (36.5%), and no improvement (37.5%). Among participants with minimal disability pre–Q-SNF, 52% demonstrated substantial improvement; the other 48% demonstrated minimal improvement (32%) or no improvement (16%) and remained moderately to severely disabled in the year post–Q-SNF. Among participants with mild disability pre–Q-SNF, 5% showed substantial improvement, whereas 95% showed little to no improvement. Of participants with moderate disability pre–Q-SNF, 15% remained moderately disabled showing little improvement, whereas 85% showed no improvement. Participants who transitioned from minimal disability pre–Q-SNF to no improvement post–Q-SNF had the highest rates of 30-day readmission and 12-month mortality (rate/100 person-days 1.3 [95% CI 0.6–2.8] and 0.3 [95% CI 0.15–0.45], respectively).ConclusionsAmong older persons, distinct disability trajectories were observed in the year before and after a Q-SNF admission. The likelihood of improvement in disability was greatly constrained by the pre–Q-SNF disability trajectory. Most older persons remained moderately to severely disabled in the year following a Q-SNF admission.
Longitudinal criminological studies greatly improved our understanding of the longitudinal patterns of criminality. These studies, however, focused almost exclusively on traditional types of offending and it is therefore unclear whether results are generalizable to online types of offending. This study attempted to identify the developmental trajectories of active hackers who perform web defacements. The data for this study consisted of 2,745,311 attacks performed by 66,553 hackers and reported to Zone-H between January 2010 and March 2017. Semi-parametric group-based trajectory models were used to distinguish six different groups of hackers based on the timing and frequency of their defacements. The results demonstrated some common relationships to traditional types of crime, as a small population of defacers accounted for the majority of defacements against websites. Additionally, the methods and targeting practices of defacers differed based on the frequency with which they performed defacements generally.
Abstract: Background: Hip fracture in older patients often lead to permanent disabilities and can result in mortality. Objective: To identify distinct disability trajectories from admission to one-year post-discharge in acutely hospitalized older patients after hip fracture. Design: Prospective cohort study, with assessments at admission, three-months and one-year post-discharge. Setting and participants: Patients ≥ 65 years admitted to a 1024-bed tertiary teaching hospital in the Netherlands. Methods: Disability was the primary outcome and measured with the modified Katz ADL-index score. A secondary outcome was mortality. Latent class growth analysis was performed to detect distinct disability trajectories from admission and Cox regression was used to analyze the effect of the deceased patients to one-year after discharge. Results: The mean (SD) age of the 267 patients was 84.0 (6.9) years. We identified 3 disability trajectories based on the Katz ADL-index score from admission to one-year post-discharge: ‘mild’- (n=54 (20.2%)), ‘moderate’- (n=110 (41.2%)) and ‘severe’ disability (n=103 (38.6%)). Patients in all three trajectories showed an increase of disabilities at three months, in relation to baseline and 80% did not return to baseline one-year post-discharge. Seventy-three patients (27.3%) deceased within one-year post-discharge, particularly in the ‘moderate’- (n=22 (8.2%)) and ‘severe’ disability trajectory (n=47 (17.6%)). Conclusions: Three disability trajectories were identified from hospital admission until one-year follow-up in acutely hospitalized older patients after hip fracture. Most patients had substantial functional decline and 27% of the patient’s deceased one-year post-discharge, mainly patients in the ‘moderate’- ‘and severe’ disability trajectories.
