An assessment of the informative value of data sharing statements in clinical trial registries

BACKGROUND

The provision of data sharing statements (DSS) for clinical trials has been made mandatory by different stakeholders. DSS are a device to clarify whether there is intention to share individual participant data (IPD). What is missing is a detailed assessment of whether DSS are providing clear and understandable information about the conditions for data sharing of IPD for secondary use.

METHODS

A random sample of 200 COVID-19 clinical trials with explicit DSS was drawn from the ECRIN clinical research metadata repository. The DSS were assessed and classified, by two experienced experts and one assessor with less experience in data sharing (DS), into different categories (unclear, no sharing, no plans, yes but vague, yes on request, yes with specified storage location, yes but with complex conditions).

RESULTS

Between the two experts the agreement was moderate to substantial (kappa=0.62, 95% CI [0.55, 0.70]). Agreement considerably decreased when these experts were compared with a third person who was less experienced and trained in data sharing ("assessor") (kappa=0.33, 95% CI [0.25, 0.41]; 0.35, 95% CI [0.27, 0.43]). Between the two experts and under supervision of an independent moderator, a consensus was achieved for those cases, where both experts had disagreed, and the result was used as "gold standard" for further analysis. At least some degree of willingness of DS (data sharing) was expressed in 63.5% (127/200) cases. Of these cases, around one quarter (31/127) were vague statements of support for data sharing but without useful detail. In around half of the cases (60/127) it was stated that IPD could be obtained by request. Only in in slightly more than 10% of the cases (15/127) it was stated that the IPD would be transferred to a specific data repository. In the remaining cases (21/127), a more complex regime was described or referenced, which could not be allocated to one of the three previous groups. As a result of the consensus meetings, the classification system was updated.

CONCLUSION

The study showed that the current DSS that imply possible data sharing are often not easy to interpret, even by relatively experienced staff. Machine based interpretation, which would be necessary for any practical application, is currently not possible. Machine learning and / or natural language processing techniques might improve machine actionability, but would represent a very substantial investment of research effort. The cheaper and easier option would be for data providers, data requestors, funders and platforms to adopt a clearer, more structured and more standardised approach to specifying, providing and collecting DSS.

TRIAL REGISTRATION

The protocol for the study was pre-registered on ZENODO ( https://zenodo.org/record/7064624#.Y4DIAHbMJD8 ).

Comparative analysis of diagnostic ultrasound and histopathology for detecting cervical lymph node metastases in head and neck cancer

PURPOSE

We evaluated the current performance of diagnostic ultrasound (US) for detecting cervical lymph node (LN) metastases based on objective measures and subjective findings in comparison to the gold standard, histopathological evaluation.

PATIENTS AND METHODS

From 2007 to 2016, we prospectively included patients with head and neck cancer who were scheduled for surgical therapy including neck dissection. LNs were examined by multimodal US by a level III head and neck sonologist and individually assigned to a map containing six AAO-HNS neck LN levels preoperatively. During the operation, LNs were dissected and then assessed by routine histopathology, with 86% of them examined individually and the remaining LNs (14%) per AAO-HNS neck LN level. The optimal cutoff points (OCPs) of four defined LN diameters and 2D and 3D roundness indices per AAO-HNS neck LN level were determined.

RESULTS

In total, 235 patients were included, and 4539 LNs were analyzed by US, 7237 by histopathology and 2684 by both methods. Of these, 259 (9.65%) were classified as suspicious for metastasis by US, whereas 299 (11.14%) were found to be positive by histopathology. Subjective US sensitivity and specificity were 0.79 and 0.99, respectively. The OCPs of the individual LN diameters and the 2D and 3D roundness index were determined individually for all AAO-HNS neck LN levels. Across all levels, the OCP for the 2D index was 1.79 and the 3D index was 14.97. The predictive performance of all distances, indices, and subjective findings improved with increasing metastasis size. Anticipation of pN stage was best achieved with subjective US findings and the smallest diameter (Cohen's κ = 0.713 and 0.438, respectively).

CONCLUSION

Our LN mapping and meticulous 1:1 node-by-node comparison reveals the usefulness of US for detecting metastatic involvement of neck LNs in head and neck carcinomas as compared to histopathology. The predictive ability for small tumor deposits less than 8 mm in size remains weak and urgently needs improvement.

Effectiveness of a complex regional advance care planning intervention to improve care consistency with care preferences: study protocol for a multi-center, cluster-randomized controlled trial focusing on nursing home residents (BEVOR trial)

Background

According to recent legislation, facilitated advance care planning (ACP) for nursing home (NH) residents is covered by German sickness funds. However, the effects of ACP on patient-relevant outcomes have not been studied in Germany yet. This study investigates whether implementing a complex regional ACP intervention improves care consistency with care preferences in NH residents.

Methods

This is a parallel-group cluster-randomized controlled trial (cRCT) with 48 NHs (≈ 3840 resident beds) between 09/2019 and 02/2023. The intervention group will receive a complex, regional ACP intervention aiming at sustainable systems redesign at all levels (individual, institutional, regional). The intervention comprises comprehensive training of ACP facilitators, implementation of reliable ACP processes, organizational development in the NH and other relevant institutions of the regional healthcare system, and education of health professionals caring for the residents. Control group NHs will deliver care as usual.

Primary outcome is the hospitalization rate during the 12-months observation period. Secondary outcomes include the rate of residents whose preferences were known and honored in potentially life-threatening events, hospital days, index treatments like resuscitation and artificial ventilation, advance directives, quality of life, psychological burden on bereaved families, and costs of care.

The NHs will provide anonymous, aggregated data of all their residents on the primary outcome and several secondary outcomes (data collection 1). For residents who have given informed consent, we will evaluate care consistency with care preferences and further secondary outcomes, based on chart reviews and short interviews with residents, surrogates, and carers (data collection 2). Process evaluation will aim to explain barriers and facilitators, economic evaluation the cost implications.

Discussion

This study has the potential for high-quality evidence on the effects of a complex regional ACP intervention on NH residents, their families and surrogates, NH staff, and health care utilization in Germany. It is the first cRCT investigating a comprehensive regional ACP intervention that aims at improving patient-relevant clinical outcomes, addressing and educating multiple institutions and health care providers, besides qualification of ACP facilitators. Thereby, it can generate evidence on the potential of ACP to effectively promote patient-centered care in the vulnerable population of frail and often chronically ill elderly.

Trial registration

ClinicalTrials.gov ID NCT04333303. Registered 30 March 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06576-3.

[Can an online risk assessment tool for identification of hereditary colorectal cancer reach the at-risk population and influence screening compliance?]

BACKGROUND AND AIM

Lynch syndrome is a frequent autosomal dominant cancer predisposition leading to an estimated incidence of 3000-4000 new cancer diagnoses of colorectal and endometrial cancer in Germany per year. The underlying hereditary condition is largely underestimated and underrecognized by physicians. The usually young at-risk population, feeling insecure about their personal risk assessment, seeks information online. The aim of this study was to evaluate whether this online risk assessment tool for identification of increased risk for hereditary cancer predisposition reaches the target population and whether it succeeds in positively influencing intensified screening compliance.

METHODS

The underlying algorithm for the test is based on the Bethesda and Amsterdam criteria and recent literature on polyposis syndromes. In the context of interrogating family and personal history, a total of five risk categories were defined. In addition to the cancers as defined in the above mentioned criteria, precursor lesions (polyps) were integrated into the risk estimate. Prior to launching, the algorithm was validated in family pedigrees of 102 mutation carriers with identified MLH-1 or MSH-2 mutations.

RESULTS

During the time interval analysed, which was between October 2008 and April 2011 a total of 656 participants were included. Among these 19.1 % (125/656) belonged to the target population at increased familial or hereditary risk. 72.8 % (91/125) were yet healthy with known cancer-affected relatives. Merely 34.4 % (11/32) of the high-risk population were currently participating in a risk adjusted screening program. After completion of the online test 62.5 % (20/32) felt motivated to reconsider and adjust accordingly with increased surveillance. The test received an overall "good" evaluation (83 %) based on handling, performance and information content.

CONCLUSION

This online risk-assessment tool was mainly completed by healthy (not cancer-affected) individuals with an increased risk for familial or hereditary colorectal cancer predisposition. The family pedigrees were comparable to these of known mutation carriers. The at-risk population was positively motivated to intensify screening strategies and the test received an overall positive evaluation.

Effect of bosentan on skin fibrosis in patients with systemic sclerosis: a prospective, open-label, non-comparative trial

OBJECTIVES

To assess the effect of the ET-receptor antagonist bosentan on skin fibrosis and functionality in patients with SSc.

METHODS

In this prospective, open-label, non-comparative trial, a total of 10 patients with SSc received 62.5 mg of bosentan twice daily for 4 weeks and then 125 mg twice daily for 20 weeks. The primary endpoint was skin thickening as measured by the modified Rodnan skin score (mRSS). Further assessments included 20 MHz ultrasound, examination of digital ulcers (DUs) and evaluation of hand function by examining patients' fist closure. Furthermore, patients with SSc used the UK SSc Functional Score (UKFS), the modified scleroderma HAQ (SHAQ) and its visual analogue scale (VAS) to rate their disability related to specific organ systems.

RESULTS

The mean change from baseline mRSS (the primary endpoint) was 6.4 at Week 24 of bosentan treatment, which was statistically significant (P < 0.001). Patients with both diffuse and limited SSc exhibited a statistically significant mean difference in the mRSS. Moreover, there was a significant healing of DUs noted between baseline and at Week 24 of bosentan treatment (P < 0.001); however, the 20 MHz ultrasound and the fist closure evaluation revealed no significant differences. There were also no statistically significant changes between baseline and Week 24 in the UKFS, the modified SHAQ and its VAS.

CONCLUSION

In addition to the well-known effect of bosentan in prevention of DUs, the results of this study demonstrate that bosentan may also be effective at reducing skin fibrosis in patients with SSc.

Dynamics of symmetry breaking and tachyonic preheating

We reconsider the old problem of the dynamics of spontaneous symmetry breaking (SSB) using 3D lattice simulations. We develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic preheating is so efficient that SSB typically completes within a single oscillation as the field rolls towards the minimum of its effective potential. We show that, contrary to previous expectations, preheating in hybrid inflation is typically tachyonic. Our results may also be relevant for the theory of the formation of topological defects and of disoriented chiral condensates in heavy ion collisions.

In vivo and in vitro stability of modified poly(urethaneurea) blood sacs

In the present study, we investigate the in vivo and in vitro stability of modified poly(urethaneurea) (BioSpan MS/0.4) blood sacs. Blood sacs were utilized primarily in left ventricular assist devices that were implanted in calves for times ranging from 5 to 160 days. Cyclic testing in vitro was also conducted on similar sacs. Various analytical methods were employed to characterize the sacs after in vivo or in vitro service and corresponding retained "control" sacs. These methods included ATR-FTIR spectroscopy, scanning electron microscopy and gel permeation chromatography. In general, the characteristics of implanted and in vitro cycled sacs were similar to their control sacs. Thermal and microtensile properties were unchanged after testing. The same was true for the ATR-FTIR spectra, indicating relative chemical stability for the time frames explored here. The only significant changes occurred in molecular weight and gross surface morphology. A modest increase in weight average molecular weight was observed for most implanted blood sacs, indicating some type of chain extension or branching reaction in vivo. Although the surface morphologies of implanted blood sacs were often similar to their control sacs, we sometimes observed limited pitting on the nonblood contacting surfaces in regions of the sac that experience maximum bending during service.

Conformal boundary conditions and three-dimensional topological field theory

We present a general construction of all correlation functions of a two-dimensional rational conformal field theory, for an arbitrary number of bulk and boundary fields and arbitrary topologies. The correlators are expressed in terms of Wilson graphs in a certain three-manifold, the connecting manifold. The amplitudes constructed this way can be shown to be modular invariant and to obey the correct factorization rules.

Steady state hemodynamic and energetic characterization of the Penn State/3M Health Care Total Artificial Heart

Total Artificial Heart (TAH) development at Penn State University and 3M Health Care has progressed from design improvements and manufacturing documentation to in vitro and in vivo testing to characterize the system's hemodynamic response and energetic performance. The TAH system is completely implantable and intended for use as an alternative to transplantation. It includes a dual pusher plate pump and rollerscrew actuator, welded electronics and battery assembly, transcutaneous energy transmission system, telemetry, and a compliance chamber. In vitro testing was conducted on a Penn State mock circulatory loop with glycerol/water solution at body temperature. Tests were performed to characterize the preload and afterload response, left atrial pressure control, and power consumption. A sensitive preload response was demonstrated with left atrial pressure safely maintained at less than 15 mm Hg for flow rates up to 7.5 L/min. Variations in aortic pressure and pulmonary vascular resistance were found to have minimal effects on the preload sensitivity and left atrial pressure control. In vivo testing of the completely implanted system in its final configuration was carried out in two acute studies using implanted temperature sensors mounted on the electronics, motor, and energy transmission coil in contact with adjacent tissue. The mean temperature at the device-tissue interface was less than 4 degrees C above core temperature.

An investigation of the in vivo stability of poly(ether urethaneurea) blood sacs

In this paper we investigate the biostability of a series of Biolon blood sacs that were utilized in electric total artificial hearts for time periods of up to 19 weeks. A battery of experimental probes, including scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), were used to characterize the bulk and surface properties of explanted and control blood sacs. Gel permeation chromatography (GPC) experiments showed that generally there was a dramatic increase in average molecular weight at longer implantation times. However, SEM and GPC observations suggest significant deterioration of the flex regions of right blood sacs after 17 weeks of service. XPS experiments indicated appreciable silicon and hydrocarbon concentrations on blood-contacting surfaces both before and after implantation, and we speculate as to their origin.

An annular compliance chamber for the Pennsylvania State University electric total artificial heart

To eliminate the need for a separate parapleural compliance chamber, we are currently investigating the feasibility of an annular compliance chamber. This chamber wraps around the energy converter and fits between the blood pumps of the Pennsylvania State University electric total artificial heart. For the 100 cc total artificial heart, the compliance chamber volume is 76 ml and the tissue contacting surface area is approximately 85 cm2. The chamber is made of Dacron velour covered segmented polyether polyurethane urea. The annular compliance chamber was evaluated in vitro by comparing pump balance control performance against that obtained with an open vent. In the CVP range of 5-12 mmHg, LAP was maintained within 1 mmHg of the values obtained with a vent. Studies continue to determine the range of volumes over which the chamber is effective, differences in rates of diffusion, and performance during changes in barometric pressure.

Electromyographic characteristics of small bowel motility in the rat

Rats are widely used in intestinal motility studies, but no precise observation has yet been carried out on the organization of motility throughout the whole small bowel of the rat. The aim of this work was to investigate the characteristics of small intestinal motility of the rat using an electromyographic technique. The variables describing the pattern of occurrence of the migrating myoelectric complex (MMC) were studied as well as the relative distribution of the 3 phases within the MMC cycles. The mean duration of the MMC was 20 min on the jejunum, and it increased up to twofold along the ileum. The propagation of the MMCs was regular in the jejunum, but about half the MMCs disappeared along the ileum and did not reach the caecum. The electromyographic characteristics of the jejunum are greatly different from those of the ileum, and the motility of a segment is not representative of the whole small bowel motility. Considering these particularities of intestinal motility, rats differ in many details from other species.

[Intestinal motility and continuous enteral nutrition: electromyographic study in dogs]

In fasting dogs, intestinal motility is characterized by the recurrence of a cyclic pattern, named the myoelectric complex; when inhibited by meals, the myoelectric complex is replaced by typical postprandial activity. Numerous studies have been performed concerning small intestinal motility but they all concerned acute food intakes. On the contrary, the aim of our work was to investigate the influence of continuous enteral nutrition in dogs for different caloric loads. The results showed that after a temporary inhibition caused by the onset of continuous enteral nutrition, the myoelectric complexes reappeared, first with long and irregular intervals of recurrence, later and finally with the same characteristics observed during the fasting state. We conclude that small intestinal motility can present the typical features of the fasting state, in spite of the presence of nutrients in the digestive tract. The factors inducing postprandial inhibition of myoelectric complexes loose their effectiveness after a period of time which depends on the caloric load in continuous enteral nutrition.

[Intestinal motility following jejunal resection: electromyography study in the rat]

The influences of massive resections on motility of the small intestine remain poorly known. The aim of our study was to determine the effects of jejunal resection on the pattern of occurrence of the migrating myoelectric complex and its postprandial inhibition. The experiments were performed over a period of 1 month after surgery. Transections were done on the jejunum or on the ileum in sham-operated animals. Ten days after resection, the motility of the anastomosed jejunal and ileal segments was dissociated. After one month, a functional continuity appeared through the anastomosis: the whole intestine worked synchronously at the same rhythm as the ileum. Food intake induced an increase in the frequency of the migrating myoelectric complexes measured 10 days after surgery. An adaptative phenomenon appeared after 30 days, the postprandial motor activity returning to its control level.