Quality of missing data reporting and handling in palliative care trials demonstrates that further development of the CONSORT statement is required: a systematic review

Eligible Infants Included in Neonatal Clinical Trials and Reasons for Noninclusion: A Systematic Review

Importance

Results of clinical trials can only represent included participants, and many neonatal trials fail due to insufficient participation. Infants not included in research may differ from those included in meaningful ways, biasing the sample and limiting the generalizability of findings.

Objective

To describe the proportion of eligible infants included in neonatal clinical trials and the reasons for noninclusion.

Evidence Review

A systematic search of Cochrane CENTRAL was performed by retrieving articles meeting the following inclusion criteria: full-length, peer-reviewed articles describing clinical trial results in at least 20 human infants from US neonatal intensive care units, published in English, and added to Cochrane CENTRAL between 2017 and 2022. Retrieved articles were screened for inclusion by 2 independent researchers.

Findings

In total 120 articles met inclusion criteria and 91 of these (75.8%) reported the number of infants eligible for participation, which totaled 26 854 in aggregate. Drawing from these, an aggregate of 11 924 eligible infants (44.4%) were included in reported results. Among all eligible infants, most reasons for noninclusion in results were classified as modifiable or potentially modifiable by the research team. Parents declining to participate (8004 infants [29.8%]) or never being approached (2507 infants [9.3%]) were the 2 predominant reasons for noninclusion. Other modifiable reasons included factors related to study logistics, such as failure to appropriately collect data on enrolled infants (859 of 26 854 infants [3.2%]) and other reasons (1907 of 26 854 infants [7.1%]), such as loss to follow-up or eligible participants that were unaccounted for. Nonmodifiable reasons, including clinical change or death, accounted for a small proportion of eligible infants who were not included (858 of 26 854 infants [3.2%]).

Conclusions and Relevance

This systematic review of reporting on eligible infants included and not included in neonatal clinical trials highlights the need for improved documentation on the flow of eligible infants through neonatal clinical trials and may also inform recruitment expectations for trialists designing future protocols. Improved adherence to standardized reporting may clarify which potential participants are being missed, improving understanding of the generalizability of research findings. Furthermore, these findings suggest that future work to understand why parents decline to participate in neonatal research trials and why some are never approached about research may help increase overall participation.

Top Ten Tips Palliative Care Clinicians Should Know About Interpreting a Clinical Trial

Evidence-based practice is foundational to high-quality palliative care delivery. However, the clinical trials that compose the evidence base are often methodologically imperfect. Applying their conclusions without critical application to the clinical practice context can harm patients. The tips provided can help clinicians infer judiciously from clinical trial results and avoid credulously accepting findings without critique. We suggest that statistical and mathematical expertise is unnecessary, but rather a keen curiosity about investigators' rationale for certain design choices and how these choices can affect results is key. For a more comprehensive understanding of clinical trials, this article can be used with the authors' corresponding ten tips article that focuses on designing a clinical trial.

REFORMS: Consensus-based Recommendations for Machine-learning-based Science

Machine learning (ML) methods are proliferating in scientific research. However, the adoption of these methods has been accompanied by failures of validity, reproducibility, and generalizability. These failures can hinder scientific progress, lead to false consensus around invalid claims, and undermine the credibility of ML-based science. ML methods are often applied and fail in similar ways across disciplines. Motivated by this observation, our goal is to provide clear recommendations for conducting and reporting ML-based science. Drawing from an extensive review of past literature, we present the REFORMS checklist (recommendations for machine-learning-based science). It consists of 32 questions and a paired set of guidelines. REFORMS was developed on the basis of a consensus of 19 researchers across computer science, data science, mathematics, social sciences, and biomedical sciences. REFORMS can serve as a resource for researchers when designing and implementing a study, for referees when reviewing papers, and for journals when enforcing standards for transparency and reproducibility.

Impact of Short-Course Palliative Radiation Therapy on Pancreatic Cancer-Related Pain: Prospective Phase 2 Nonrandomized PAINPANC Trial

PURPOSE

Clinical evidence is limited regarding palliative radiation therapy for relieving pancreatic cancer-related pain. We prospectively investigated pain response after short-course palliative radiation therapy in patients with moderate-to-severe pancreatic cancer-related pain.

METHODS AND MATERIALS

In this prospective phase 2 single center nonrandomized trial, 30 patients with moderate-to-severe pain (5-10, on a 0-10 scale) of pancreatic cancer refractory to pain medication, were treated with a short-course palliative radiation therapy; 24 Gy in 3 weekly fractions (2015-2018). Primary endpoint was defined as a clinically relevant average decrease of ≥2 points in pain severity, compared with baseline, within 7 weeks after the start of treatment. Secondary endpoint was global quality of life (QoL), with a clinically relevant increase of 5 to 10 points (0-100 scale). Pain severity reduction and QoL were assessed 9 times using the Brief Pain Inventory and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C15-PAL, respectively. Both outcomes were analyzed using joint modeling. In addition, acute toxicity based on clinician reporting and overall survival (OS) were assessed.

RESULTS

Overall, 29 of 30 patients (96.7%) received palliative radiation therapy. At baseline, the median oral morphine equivalent daily dose was 129.5 mg (range, 20.0-540.0 mg), which decreased to 75.0 mg (range, 15.0-360.0 mg) after radiation (P = .021). Pain decreased on average 3.15 points from baseline to 7 weeks (one-sided P = .045). Patients reported a clinically relevant mean pain severity reduction from 5.9 to 3.8 points (P = .011) during the first 3 weeks, which further decreased to 3.2 until week 11, ending at 3.4 (P = .006) in week 21 after the first radiation therapy fraction. Global QoL significantly improved from 50.5 to 60.8 during the follow-up period (P = .001). Grade 3 acute toxicity occurred in 3 patients and no grade 4 to 5 toxicity was observed. Median OS was 11.8 weeks, with a 13.3% 1-year actuarial OS rate.

CONCLUSIONS

Short-course palliative radiation therapy for pancreatic cancer-related pain was associated with rapid, clinically relevant reduction in pain severity, and clinically relevant improvement in global QoL, with mostly mild toxicity.

Trial arm outcome variance difference after dropout as an indicator of missing-not-at-random bias in randomized controlled trials

Randomized controlled trials (RCTs) are vulnerable to bias from missing data. When outcomes are missing not at random (MNAR), estimates from complete case analysis (CCA) and multiple imputation (MI) may be biased. There is no statistical test for distinguishing between outcomes missing at random (MAR) and MNAR. Current strategies rely on comparing dropout proportions and covariate distributions, and using auxiliary information to assess the likelihood of dropout being associated with the outcome. We propose using the observed variance difference across trial arms as a tool for assessing the risk of dropout being MNAR in RCTs with continuous outcomes. In an RCT, at randomization, the distributions of all covariates should be equal in the populations randomized to the intervention and control arms. Under the assumption of homogeneous treatment effects and homoskedastic outcome errors, the variance of the outcome will also be equal in the two populations over the course of follow-up. We show that under MAR dropout, the observed outcome variances, conditional on the variables included in the model, are equal across trial arms, whereas MNAR dropout may result in unequal variances. Consequently, unequal observed conditional trial arm variances are an indicator of MNAR dropout and possible bias of the estimated treatment effect. Heterogeneous treatment effects or heteroskedastic outcome errors are another potential cause of observing different outcome variances. We show that for longitudinal data, we can isolate the effect of MNAR outcome-dependent dropout by considering the variance difference at baseline in the same set of patients who are observed at final follow-up. We illustrate our method in simulation for CCA and MI, and in applications using individual-level data and summary data.

Palliative clinical trials in advanced chronic liver disease: Challenges and opportunities

Patients with advanced chronic liver disease have a complex symptom burden and many are not candidates for curative therapy. Despite this, provision of palliative interventions remains woefully inadequate, with an insufficient evidence base being a contributory factor. Designing and conducting palliative interventional trials in advanced chronic liver disease remains challenging for a multitude of reasons. In this manuscript we review past and ongoing palliative interventional trials. We identify barriers and facilitators and offer guidance on addressing these challenges. We hope that this will reduce the inequity in palliative care provision in advanced chronic liver disease.

[Transition from intensive care to palliative care : A retrospective analysis of 102 consultation requests]

BACKGROUND

The transition of patients from the intensive care unit (ICU) to the palliative care (PC) ward often implies changes including establishing a palliative concept. Adaptation of therapeutic goals can be challenging for medical staff, patients and relatives; however, descriptions of these transition trajectories are rare.

OBJECTIVE

The aim of this retrospective study was to characterize the consultation requests of the ICU to the PC consultation team as well as the patients by a description of trajectories and interventions.

METHODS

Retrospective analysis of all patients receiving intensive care at RWTH Aachen University Hospital in 2019 for whom a PC consultation was requested. The patient population transferred from the ICU to the PC ward was compared with the non-transferred population. In each case, the primary consultation was evaluated regarding the following factors: question, vigilance, length of time from consultation request to its performance, and primary focus of the question. The question focus was categorized into "symptom control", "counselling" and "transfer" (tick options). In addition, a free text field was available for further notes. Exploration of diagnoses was complemented by accessing the electronic health records.

RESULTS

A total of 102 consultation requests from the ICU to the PC ward were evaluated. The morbidity of patients was high, and most patients had at least one of the following diagnoses: pulmonary (62%), cardiovascular (61%), and/or neurological disease (55%). Of the patients 32 (31%) were transferred to the PC ward, among whom weakness (94%), fatigue (77%), anxiety (55%), pain (53%), and dyspnea (48%) were the most frequently noted symptoms. Of the transferred patients 5 (16%) could be discharged to home, nursing home, hospice or other. In total, 35 (34%) of all patients who were seen by palliative care specialists on ICUs in 2019 could be discharged alive. The most frequent reasons for nonadmission were lack of capacity of the PC ward (33%), dying while being on the waiting list (20%), and refusal by the patient (20%). Of the patients, 7 (26%) died within 48 h after they had been transferred to the PC ward. Performed consultation services "symptom control" (χ2 = 10.17; p < 0.05) and "counselling" (χ2 = 12.82; p < 0.001), which were requested by the intensive care physicians, showed a significant linkage with the respective intervention performed by the palliative care team. On the other hand, no statistically significant difference was found for requested and performed "transfer" of patients from ICUs to PC ward. Comparing the transferred versus non-transferred patient population, a significantly more frequent transfer of patients with malignant tumors (p = 0.00) was observed.

CONCLUSION

The need for palliative care support in the ICUs exceeded the admission capacity of the PC ward. Future studies should further examine palliative care models in intensive care medicine.

[DNVF Memorandum: Health Services Research in the Last Year of Life]

This memorandum outlines current issues concerning health services research on seriously ill and dying people in the last year of their lives as well as support available for their relatives. Patients in the last phase of life can belong to different disease groups, they may have special characteristics (e. g., people with cognitive and complex impairments, economic disadvantage or migration background) and be in certain phases of life (e. g., parents of minor children, (old) age). The need for a designated memorandum on health services research in the last year of life results from the special situation of those affected and from the special features of health services in this phase of life. With reference to these special features, this memorandum describes methodological and ethical specifics as well as current issues in health services research and how these can be adequately addressed using quantitative, qualitative and mixed methods. It has been developed by the palliative medicine section of the German Network for Health Services Research (DNVF) according to the guidelines for DNVF memoranda.

Reporting of Patient-Reported Outcome Measures in Randomized Controlled Trials on Shoulder Rotator Cuff Injuries Is Suboptimal and Requires Standardization

Purpose

Methods

Results

Conclusions

Clinical Relevance

The evaluation of reporting of patient-reported outcomes in MDD: A meta-epidemiological study of clinical trials

Major depressive disorder (MDD) is a multifaceted disease that profoundly affects quality of life. Patient reported outcomes (PROs) are used in randomized controlled trials (RCTs) to better understand patient perspectives on interventions. Therefore, we sought to assess the completeness of reporting PROs in RCTs addressing MDD. We identified RCTs evaluating MDD containing a PRO measure published between 2016 and 2020 from MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials. Inclusion of studies was performed in duplicate. The completion of reporting of RCTs was assessed using the Consolidated Standards of Reporting Trials (CONSORT-PRO) adaptation. Bivariate regression analyses were used to evaluate reporting completeness and trial characteristics. A total of 49 RCTs were included in our analysis, with a mean CONSORT-PRO completion score of 56.7% (SD = 17.3).Our findings show a significant association with completeness of reporting and the following: secondary PRO trials were less completely reported as compared to primary PRO trials (t = -3.19, p = .003); studies with a follow-up period between six months and year were more completely reported as compared to three months or less (6 months to a year, t = 2.34, p = .024); and increased trial sample size was associated with more completeness of reporting (t = 3.17, p = .003). As compared to brain stimulation, the intervention types classified as combination, other, and psychotherapy had greater completeness of reporting (combination, t = 2.35, p = .024; other, t = 3.13, p = .003; psychotherapy, t = 3.41, p = .001). There were no other significant findings. Our study found the completeness of PRO reporting to be inconsistent in RCTs regarding MDD. Moreover, we advocate for the need to establish a core outcome set relevant to the management of adults diagnosed with MDD and facilitate training on the application of PRO data.

The reporting and handling of missing data in longitudinal studies of older adults is suboptimal: a methodological survey of geriatric journals

Background

Missing data are common in longitudinal studies, and more so, in studies of older adults, who are susceptible to health and functional decline that limit completion of assessments. We assessed the extent, current reporting, and handling of missing data in longitudinal studies of older adults.

Methods

Medline and Embase databases were searched from 2015 to 2019 for publications on longitudinal observational studies conducted among persons ≥55 years old. The search was restricted to 10 general geriatric journals published in English. Reporting and handling of missing data were assessed using questions developed from the recommended standards. Data were summarised descriptively as frequencies and proportions.

Results

A total of 165 studies were included in the review from 7032 identified records. In approximately half of the studies 97 (62.5%), there was either no comment on missing data or unclear descriptions. The percentage of missing data varied from 0.1 to 55%, with a 14% average among the studies that reported having missing data. Complete case analysis was the most common method for handling missing data with nearly 75% of the studies (n = 52) excluding individual observations due to missing data, at the initial phase of study inclusion or at the analysis stage. Of the 10 studies where multiple imputation was used, only 1 (10.0%) study followed the guideline for reporting the procedure fully using online supplementary documents.

Conclusion

The current reporting and handling of missing data in longitudinal observational studies of older adults are inadequate. Journal endorsement and implementation of guidelines may potentially improve the quality of missing data reporting. Further, authors should be encouraged to use online supplementary files to provide additional details on how missing data were addressed, to allow for more transparency and comprehensive appraisal of studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01605-w.

Handling Missing Data and Drop Out in Hospice/Palliative Care Trials Through the Estimand Framework

CONTEXT

Missing data are common in hospice/palliative care randomized trials due to high drop-out because of the demographic of interest. It can introduce bias in the estimate of the treatment effect and its precision.

OBJECTIVES

The International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) released updated guidance on statistical principles for clinical trials introducing the estimand framework to align trial objectives, trial conduct, statistical analysis and interpretation of results. Our objective is to present how the estimand framework can be used to guide the handling of missing data in palliative care trials.

METHODS

We outline the estimand framework by highlighting the five elements of an estimand: treatment, population, variable, summary measure and intercurrent event handling. We list common intercurrent events in palliative care trials and present the five strategies for handling intercurrent events outlined in the ICH guidance.

RESULTS

We describe common intercurrent events in palliative care trials and discuss and justify what analytic strategies could be followed with each. We provide an example using a palliative care trial comparing two opioids for pain relieve in participants with cancer pain.

CONCLUSION

When planning a palliative care trial, the estimand should be explicitly stated, including how intercurrent events will be handled in the analysis. This should be informed by the scientific objectives of the trial. The estimand guides the handling of missing data during the conduct and analysis of the trial. Defining an estimand is not a statistical activity, but a multi-disciplinary process involving all stakeholders.

Increased transparency was required when reporting imputation of primary outcome data in clinical trials

OBJECTIVE

To explore the transparency of reporting primary outcome data within randomised controlled trials (RCTs) in the presence of missing data.

STUDY DESIGN

/ Setting: A cohort examination of RCTs published in the four major medical journals (NEJM, JAMA, BMJ, Lancet) in 2013 and the first quarter of 2018. Data was extracted on reporting quality, the number of randomised participants and the number of participants included within the primary outcome analysis with observed or imputed data.

RESULTS

91/159 (57%) of the studies analysed from 2013 and 19/46 (41%) from 2018 included imputed data within the primary outcome analysis. Of these, only 13/91 (14%) studies from 2013 and 1/19 (5%) studies from 2018 explicitly reported the number of imputed values in the CONSORT diagram. Results tables included levels of imputed data in 12/91 (13%) studies in 2013 and 4/19 (21%) in 2018. Consequently, identification of imputed data was a time-consuming task requiring extensive cross-referencing of all manuscript elements.

CONCLUSION

Imputed primary outcome data is poorly reported. Participant flow diagrams frequently reported participant status which does not necessarily correlate to availability of data. We recommended that the number of imputed values are explicitly reported within CONSORT flow diagrams to increase transparency.

Developing an online, searchable database to systematically map and organise current literature on retention research (ORRCA2)

BACKGROUND

Addressing recruitment and retention challenges in trials is a key priority for methods research, but navigating the literature is difficult and time-consuming. In 2016, ORRCA (www.orrca.org.uk) launched a free, searchable database of recruitment research that has been widely accessed and used to support the update of systematic reviews and the selection of recruitment strategies for clinical trials. ORRCA2 aims to create a similar database to map the growing volume and importance of retention research.

METHODS

Searches of Medline (Ovid), CINAHL, PsycINFO, Scopus, Web of Science Core Collection and the Cochrane Library, restricted to English language and publications up to the end of 2017. Hand searches of key systematic reviews were undertaken and randomised evaluations of recruitment interventions within the ORRCA database on 1 October 2020 were also reviewed for any secondary retention outcomes. Records were screened by title and abstract before obtaining the full text of potentially relevant articles. Studies reporting or evaluating strategies, methods and study designs to improve retention within healthcare research were eligible. Case reports describing retention challenges or successes and studies evaluating participant reported reasons for withdrawal or losses were also included. Studies assessing adherence to treatments, attendance at appointments outside of research and statistical analysis methods for missing data were excluded. Eligible articles were categorised into one of the following evidence types: randomised evaluations, non-randomised evaluations, application of retention strategies without evaluation and observations of factors affecting retention. Articles were also mapped against a retention domain framework. Additional data were extracted on research outcomes, methods and host study context.

RESULTS

Of the 72,904 abstracts screened, 4,364 full texts were obtained, and 1,167 articles were eligible. Of these, 165 (14%) were randomised evaluations, 99 (8%) non-randomised evaluations, 319 (27%) strategies without evaluation and 584 (50%) observations of factors affecting retention. Eighty-four percent (n = 979) of studies assessed the numbers of participants retained, 27% (n = 317) assessed demographic differences between retained and lost participants, while only 4% (n = 44) assessed the cost of retention strategies. The most frequently reported domains within the 165 studies categorised as 'randomised evaluations of retention strategies' were participant monetary incentives (32%), participant reminders and prompts (30%), questionnaire design (30%) and data collection location and method (26%).

CONCLUSION

ORRCA2 builds on the success of ORRCA extending the database to organise the growing volume of retention research. Less than 15% of articles were randomised evaluations of retention strategies. Mapping of the literature highlights several areas for future research such as the role of research sites, clinical staff and study design in enhancing retention. Future studies should also include cost-benefit analysis of retention strategies.

Sensitivity to missing not at random dropout in clinical trials: Use and interpretation of the trimmed means estimator

Outcome values in randomized controlled trials (RCTs) may be missing not at random (MNAR), if patients with extreme outcome values are more likely to drop out (eg, due to perceived ineffectiveness of treatment, or adverse effects). In such scenarios, estimates from complete case analysis (CCA) and multiple imputation (MI) will be biased. We investigate the use of the trimmed means (TM) estimator for the case of univariable missingness in one continuous outcome. The TM estimator operates by setting missing values to the most extreme value, and then “trimming” away equal fractions of both groups, estimating the treatment effect using the remaining data. The TM estimator relies on two assumptions, which we term the “strong MNAR” and “location shift” assumptions. We derive formulae for the TM estimator bias resulting from the violation of these assumptions for normally distributed outcomes. We propose an adjusted TM estimator, which relaxes the location shift assumption and detail how our bias formulae can be used to establish the direction of bias of CCA and TM estimates, to inform sensitivity analyses. The TM approach is illustrated in a sensitivity analysis of the CoBalT RCT of cognitive behavioral therapy (CBT) in 469 individuals with 46 months follow‐up. Results were consistent with a beneficial CBT treatment effect, with MI estimates closer to the null and TM estimates further from the null than the CCA estimate. We propose using the TM estimator as a sensitivity analysis for data where extreme outcome value dropout is plausible.

Development of guidelines to reduce, handle and report missing data in palliative care trials: A multi-stakeholder modified nominal group technique

BACKGROUND

Missing data can introduce bias and reduce the power, precision and generalisability of study findings. Guidelines on how to address missing data are limited in scope and detail, and poorly implemented.

AIM

To develop guidelines on how best to (i) reduce, (ii) handle and (iii) report missing data in palliative care clinical trials.

DESIGN

Modified nominal group technique.

SETTING/PARTICIPANTS

Patient and public research partners, palliative care clinicians, trialists, methodologists and statisticians attended a 1-day workshop, following which a multi-stakeholder development group drafted the guidelines.

RESULTS

Seven main recommendations for reducing missing data, nine for handling missing data and twelve for reporting missing data were developed. The top five recommendations were: (i) train all research staff on missing data, (ii) prepare for missing data at the trial design stage, (iii) address missing data in the statistical analysis plan, (iv) collect the reasons for missing data and (v) report descriptive statistics comparing the baseline characteristics of those with missing and observed data. Reducing missing data, preparing for missing data and understanding the reasons for missing data were greater priorities for stakeholders than how to deal with missing data once they had occurred.

CONCLUSION

Comprehensive guidelines on how to address missing data were developed by stakeholders involved in palliative care trials. Implementation of the guidelines will require endorsement of research funders and research journals.

Successful Strategies and Areas of Improvement-Lessons Learned from Design and Conduction of a Randomized Placebo-Controlled Trial in Palliative Care, 'Palliative-D'

Clinical trials in palliative care are challenging to design and conduct. Burden on patients should be minimized, while gatekeeping by professionals and next-of kin needs to be avoided. Clinical deterioration due to disease progression affects attrition unrelated to intervention, and different care settings complicate comparisons and reduce the generalizability of the results. The aim of this review is to provide advice for colleagues planning to perform clinical trials in palliative care based on our own experiences from performing the Palliative-D study and by a thorough literature review on this topic. The Palliative-D study was a double-blind trial with 244 randomized patients comparing the effect of vitamin D₃ to placebo in patients with advanced or metastatic cancer in the palliative phase of their disease trajectory who were enrolled in specialized palliative home care teams. Endpoints were opioid and antibiotic use, fatigue, and QoL. Recruitment was successful, but attrition rates were higher than expected, and we did not reach targeted power. For the 150 patients who completed the study, the completeness of the data was exceptionally high. Rather than patient reported pain, we choose the difference in the mean change in opioid dose between groups after twelve weeks compared to baseline as the primary endpoint. In this paper we discuss challenges in palliative care research based on lessons learned from the "Palliative-D" trial regarding successful strategies as well as areas for improvement.

Missing not at random in end of life care studies: multiple imputation and sensitivity analysis on data from the ACTION study

Background

Missing data are common in end-of-life care studies, but there is still relatively little exploration of which is the best method to deal with them, and, in particular, if the missing at random (MAR) assumption is valid or missing not at random (MNAR) mechanisms should be assumed. In this paper we investigated this issue through a sensitivity analysis within the ACTION study, a multicenter cluster randomized controlled trial testing advance care planning in patients with advanced lung or colorectal cancer.

Methods

Multiple imputation procedures under MAR and MNAR assumptions were implemented. Possible violation of the MAR assumption was addressed with reference to variables measuring quality of life and symptoms. The MNAR model assumed that patients with worse health were more likely to have missing questionnaires, making a distinction between single missing items, which were assumed to satisfy the MAR assumption, and missing values due to completely missing questionnaire for which a MNAR mechanism was hypothesized. We explored the sensitivity to possible departures from MAR on gender differences between key indicators and on simple correlations.

Results

Up to 39% of follow-up data were missing. Results under MAR reflected that missingness was related to poorer health status. Correlations between variables, although very small, changed according to the imputation method, as well as the differences in scores by gender, indicating a certain sensitivity of the results to the violation of the MAR assumption.

Conclusions

The findings confirmed the importance of undertaking this kind of analysis in end-of-life care studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-020-01180-y.

Does acupressure help reduce nausea and vomiting in palliative care patients? A double blind randomised controlled trial

INTRODUCTION

Nausea and vomiting are common symptoms for patients with advanced cancer. While there is evidence for acupuncture point stimulation for treatment of these symptoms for patients having anticancer treatment, there is little for when they are not related to such treatment.

OBJECTIVE

To determine whether acupressure at the pericardium 6 site can help in the treatment of nausea and vomiting suffered by palliative care patients with advanced cancer.

MATERIALS AND METHODS

Double blind randomised controlled trial-active versus placebo acupressure wristbands. In-patients with advanced cancer in two specialist palliative care units who fitted either or both of the following criteria were approached: Nausea that was at least moderate; Vomiting daily on average for the prior 3 days.

RESULTS

57 patients were randomised to have either active or placebo acupressure wristbands. There was no difference in any of the outcome measures between the two groups: change from baseline number of vomits; Visual Analogue Scale for 'did acupressure wristbands help you to feel better?'; total number of as needed doses of antiemetic medication; need for escalation of antiemetics.

CONCLUSIONS

In contrast to a previously published feasibility study, active acupressure wristbands were no better than placebo for specialist palliative care in-patients with advanced cancer and nausea and vomiting.

Potential impact of missing outcome data on treatment effects in systematic reviews: imputation study

OBJECTIVE

To assess the risk of bias associated with missing outcome data in systematic reviews.

DESIGN

Imputation study.

SETTING

Systematic reviews.

POPULATION

100 systematic reviews that included a group level meta-analysis with a statistically significant effect on a patient important dichotomous efficacy outcome.

MAIN OUTCOME MEASURES

Median percentage change in the relative effect estimate when applying each of the following assumption (four commonly discussed but implausible assumptions (best case scenario, none had the event, all had the event, and worst case scenario) and four plausible assumptions for missing data based on the informative missingness odds ratio (IMOR) approach (IMOR 1.5 (least stringent), IMOR 2, IMOR 3, IMOR 5 (most stringent)); percentage of meta-analyses that crossed the threshold of the null effect for each method; and percentage of meta-analyses that qualitatively changed direction of effect for each method. Sensitivity analyses based on the eight different methods of handling missing data were conducted.

RESULTS

100 systematic reviews with 653 randomised controlled trials were included. When applying the implausible but commonly discussed assumptions, the median change in the relative effect estimate varied from 0% to 30.4%. The percentage of meta-analyses crossing the threshold of the null effect varied from 1% (best case scenario) to 60% (worst case scenario), and 26% changed direction with the worst case scenario. When applying the plausible assumptions, the median percentage change in relative effect estimate varied from 1.4% to 7.0%. The percentage of meta-analyses crossing the threshold of the null effect varied from 6% (IMOR 1.5) to 22% (IMOR 5) of meta-analyses, and 2% changed direction with the most stringent (IMOR 5).

CONCLUSION

Even when applying plausible assumptions to the outcomes of participants with definite missing data, the average change in pooled relative effect estimate is substantive, and almost a quarter (22%) of meta-analyses crossed the threshold of the null effect. Systematic review authors should present the potential impact of missing outcome data on their effect estimates and use this to inform their overall GRADE (grading of recommendations assessment, development, and evaluation) ratings of risk of bias and their interpretation of the results.

Outcome reporting recommendations for clinical trial protocols and reports: a scoping review

BACKGROUND

Clinicians, patients, and policy-makers rely on published evidence from clinical trials to help inform decision-making. A lack of complete and transparent reporting of the investigated trial outcomes limits reproducibility of results and knowledge synthesis efforts, and contributes to outcome switching and other reporting biases. Outcome-specific extensions for the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT-Outcomes) and Consolidated Standards of Reporting Trials (CONSORT-Outcomes) reporting guidelines are under development to facilitate harmonized reporting of outcomes in trial protocols and reports. The aim of this review was to identify and synthesize existing guidance for trial outcome reporting to inform extension development.

METHODS

We searched for documents published in the last 10 years that provided guidance on trial outcome reporting using: an electronic bibliographic database search (MEDLINE and the Cochrane Methodology Register); a grey literature search; and solicitation of colleagues using a snowballing approach. Two reviewers completed title and abstract screening, full-text screening, and data charting after training. Extracted trial outcome reporting guidance was compared with candidate reporting items to support, refute, or refine the items and to assess the need for the development of additional items.

RESULTS

In total, 1758 trial outcome reporting recommendations were identified within 244 eligible documents. The majority of documents were published by academic journals (72%). Comparison of each recommendation with the initial list of 70 candidate items led to the development of an additional 62 items, producing 132 candidate items. The items encompassed outcome selection, definition, measurement, analysis, interpretation, and reporting of modifications between trial documents. The total number of documents supporting each candidate item ranged widely (median 5, range 0-84 documents per item), illustrating heterogeneity in the recommendations currently available for outcome reporting across a large and diverse sample of sources.

CONCLUSIONS

Outcome reporting guidance for clinical trial protocols and reports lacks consistency and is spread across a large number of sources that may be challenging to access and implement in practice. Evidence and consensus-based guidance, currently in development (SPIRIT-Outcomes and CONSORT-Outcomes), may help authors adequately describe trial outcomes in protocols and reports transparently and completely to help reduce avoidable research waste.

Systematic Review of the Role of Stereotactic Radiotherapy for Bone Metastases

Background

Stereotactic radiotherapy (SBRT) might improve pain and local control in patients with bone metastases compared to conventional radiotherapy, although an overall estimate of these outcomes is currently unknown.

Methods

A systematic review was carried out following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pubmed, Embase, and Cochrane databases were systematically searched to identify studies reporting pain response and local control among patients with bone metastases from solid-organ tumors who underwent SBRT in 1–6 fractions. All studies prior to April 15, 2017, were included. Study quality was assessed by predefined criteria, and pain response and local control rates were extracted.

Results

A total of 2619 studies were screened; 57 were included (reporting outcomes for 3995 patients) of which 38 reported pain response and 45 local control rates. Local control rates were high with pain response rates above those previously reported for conventional radiotherapy. Marked heterogeneity in study populations and delivered treatments were identified such that quantitative synthesis was not appropriate. Reported toxicity was limited. Of the pain response studies, 73.7% used a retrospective cohort design and only 10.5% used the international consensus endpoint definitions of pain response. The median survival within the included studies ranged from 8 to 30.4 months, suggesting a high risk of selection bias in the included observational studies.

Conclusions

This review demonstrates the potential benefit of SBRT over conventional palliative radiotherapy in improving pain due to bone metastases. Given the methodological limitations of the published literature, however, large randomized trials are now urgently required to better quantify this benefit.

What influenced people with chronic or refractory breathlessness and advanced disease to take part and remain in a drug trial? A qualitative study

BACKGROUND

Recruitment and retention in clinical trials remains an important challenge, particularly in the context of advanced disease. It is important to understand what affects retention to improve trial quality, minimise attrition and reduce missing data. We conducted a qualitative study embedded within a randomised feasibility trial and explored what influenced people to take part and remain in the trial.

METHODS

We conducted a qualitative study embedded within a double-blind randomised trial (BETTER-B[Feasibility]: BETter TreatmEnts for Refractory Breathlessness) designed using a person-centred approach. Participants with cancer, chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), or chronic heart failure (CHF), with a modified Medical Research Council dyspnoea scale grade of 3/4 were recruited from three UK sites. A convenience subsample completed qualitative interviews after the trial. Interviews were analysed using thematic analysis. Results were considered in relation to the core elements of person-centred care and our model of the person-centred trial.

RESULTS

In the feasibility trial 409 people were screened for eligibility, and 64 were randomised. No participant was lost to follow-up. Twenty-two participants took part in a qualitative interview. Eleven had a diagnosis of COPD, 8 ILD, 2 CHF and 1 lung cancer. The participants' median age was 71 years (range 56-84). Sixteen were male. Twenty had completed the trial, and two withdrew due to adverse effects. The relationship between patient and professional, potential for benefit, trial processes and the intervention all influenced the decision to participate in the trial. The relationship with the research team and continuity, perceived benefit, and aspects relating to trial processes and the intervention influenced the decision to remain in the trial.

CONCLUSIONS

In this feasibility trial recruitment targets were met, attrition levels were low, and aspects of the person-centred approach were viewed positively by trial participants. Prioritisation of the relationship between the patient and professional; person-centred processes, including home visits, assistance with questionnaires, and involvement of the carer; and enabling people to participate by having processes in line with individual capabilities appear to support recruitment and retention in clinical trials in advanced disease. We recommend the integration of a person-centred approach in all clinical trials.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN32236160. Registered on 13 June 2016.

Dealing with missing outcome data in meta-analysis

Missing data result in less precise and possibly biased effect estimates in single studies. Bias arising from studies with incomplete outcome data is naturally propagated in a meta-analysis. Conventional analysis using only individuals with available data is adequate when the meta-analyst can be confident that the data are missing at random (MAR) in every study-that is, that the probability of missing data does not depend on unobserved variables, conditional on observed variables. Usually, such confidence is unjustified as participants may drop out due to lack of improvement or adverse effects. The MAR assumption cannot be tested, and a sensitivity analysis to assess how robust results are to reasonable deviations from the MAR assumption is important. Two methods may be used based on plausible alternative assumptions about the missing data. Firstly, the distribution of reasons for missing data may be used to impute the missing values. Secondly, the analyst may specify the magnitude and uncertainty of possible departures from the missing at random assumption, and these may be used to correct bias and reweight the studies. This is achieved by employing a pattern mixture model and describing how the outcome in the missing participants is related to the outcome in the completers. Ideally, this relationship is informed using expert opinion. The methods are illustrated in two examples with binary and continuous outcomes. We provide recommendations on what trial investigators and systematic reviewers should do to minimize the problem of missing outcome data in meta-analysis.

Methodological challenges in conducting instrumentation research in non-communicative palliative care patients

Well-designed, rigorously implemented instrumentation studies are essential to develop valid, reliable pain assessment tools in non-communicative (non-self-reporting) palliative care patients. When conducting a pain instrumentation study, a research team identified methodologic challenges surrounding informed consent, eligibility criteria, acute pain operational definitions, patient recruitment, missing data, and study-related training during a run-in phase at the beginning of the project and during the conduct of the study. The team dealt with these challenges through identifying root causes, implementing remedial measures, and collecting data to demonstrate improvement or resolution. Effective strategies included obtaining Institutional Review Board (IRB) approval for a waiver of informed consent, modifying eligibility criteria, ensuring that operational definitions and study procedures were consistent with clinical practice, decreasing time from screening to data collection to improve recruitment, increasing study nurse staffing by re-budgeting grant funds, focusing time and resources on high accruing clinical units, revising processes to minimize missing data, and developing detailed training for users of the instrument. With these multi-pronged solutions, the team exceeded the patient accrual target by 25% within the funding period and reduced missing data. While pain instrumentation studies in non-communicative patients have similar challenges to other palliative care studies, some of the solutions may be unique and several are applicable to other palliative care studies, particularly instrumentation research. The team's experience may also be useful for funders and IRBs.

Multi-disciplinary palliative care is effective in people with symptomatic heart failure: A systematic review and narrative synthesis

BACKGROUND

Despite recommendations, people with heart failure have poor access to palliative care.

AIM

To identify the evidence in relation to palliative care for people with symptomatic heart failure.

DESIGN

Systematic review and narrative synthesis. (PROSPERO CRD42016029911).

DATA SOURCES

Databases (Medline, Cochrane database, CINAHL, PsycINFO, HMIC, CareSearch Grey Literature), reference lists and citations were searched and experts contacted. Two independent reviewers screened titles and abstracts and retrieved papers against inclusion criteria. Data were extracted from included papers and studies were critically assessed using a risk of bias tool according to design.

RESULTS

Thirteen interventional and 10 observational studies were included. Studies were heterogeneous in terms of population, intervention, comparator, outcomes and design rendering combination inappropriate. The evaluation phase studies, with lower risk of bias, using a multi-disciplinary specialist palliative care intervention showed statistically significant benefit for patient-reported outcomes (symptom burden, depression, functional status, quality of life), resource use and costs of care. Benefit was not seen in studies with a single component/discipline intervention or with higher risk of bias. Possible contamination in some studies may have caused under-estimation of effect and missing data may have introduced bias. There was no apparent effect on survival.

CONCLUSION

Overall, the results support the use of multi-disciplinary palliative care in people with advanced heart failure but trials do not identify who would benefit most from specialist palliative referral. There are no sufficiently robust multi-centre evaluation phase trials to provide generalisable findings. Use of common population, intervention and outcomes in future research would allow meta-analysis.

Net Pain Relief After Palliative Radiation Therapy for Painful Bone Metastases: A Useful Measure to Reflect Response Duration? A Further Analysis of the Dutch Bone Metastasis Study

Purpose

Pain response rates are equivalent after single 8 Gy and fractionated palliative radiation therapy for bone metastases. Reirradiation remains more frequent after a single fraction, although this does not simply reflect pain recurrence. Given the possible role of stereotactic radiation therapy in providing durable pain control, measures of durability are required. Net pain relief (NPR), the proportion of remaining life spent with pain response, may provide this. This study assesses the use of NPR as an outcome measure after palliative radiation therapy for bone metastases.

Methods and Materials

This is a secondary analysis of data collected in the Dutch Bone Metastasis Study, a randomized trial comparing palliative radiation therapy delivered as 8 Gy in a single fraction and 24 Gy in 6 fractions. NPR was assessed by survival cohorts, treatment regimen, and primary diagnoses. The consequences of missing data upon the use of NPR in future studies were considered within sensitivity analyses.

Results

Patients whose pain improved after palliative radiation therapy experienced improvement for 56.6% of their remaining lives. Missing responses in questionnaires mean the range of uncertainty in NPR is 36.1% to 62.1%. When response beyond reirradiation was excluded, NPR after treatments of single-fraction 8 Gy and 24 Gy in 6 fractions was 49.0% and 56.5%, respectively (P = .004). Differential willingness to reirradiate may be influencing this outcome. When response beyond reirradiation was included, this difference was not seen (NPR of 55.4% vs 57.7%, respectively [P = .191]).

Conclusions

Patients who responded to conventional radiation therapy experienced improved pain control for approximately half of their remaining life. NPR may provide valuable information in assessing pain response durability. Missing data are, however, inevitable in this population. This must be minimized and the consequences recognized and reported. Additionally, reirradiation protocols and the frequency and duration of trial follow-up may have a significant impact upon this outcome, requiring careful consideration during trial design if NPR is to be used in future studies.

Reducing attrition within clinical trials: The communication of retention and withdrawal within patient information leaflets

BACKGROUND

The recruitment and retention of patients are significant methodological challenges for trials. Whilst research has focussed on recruitment, the failure to retain recruited patients and collect outcome data can lead to additional problems and potentially biased results. Research to identify effective retention strategies has focussed on influencing patient behaviour through incentives, reminders and alleviating patient burden, but has not sought to improve patient understanding of the importance of retention. Our aim is to assess how withdrawal, retention and the value of outcome data collection is described within the Patient Information Leaflets (PIL) used during consent.

METHODS

Fifty adult or parent PIL from a cohort of trials starting between 2009-2012 and funded by the NIHR Health Technology Assessment programme were obtained from protocols, websites or by contacting trialists. A checklist of PIL content based on Health Research Authority (HRA) and ICH GCP Guidelines was supplemented with retention specific questions. Corresponding protocols were also evaluated to cross reference trial specific procedures with information communicated to patients.

RESULTS

PIL frequently reiterated the patient's right to withdraw at any time (n = 49, 98%), without having to give a reason and without penalty (n = 45, 90%). However, few informed patients they may be asked to give a withdrawal reason where willing (n = 6, 12%). Statements about the value of retention were infrequent (n = 8, 16%). Consent documents failed to include key content that might mitigate withdrawals, such as the need for treatment equipoise (n = 3, 6%). Nearly half the trials in the cohort (n = 23, 46%) wanted to continue to collect outcome data if patients withdraw. However, in 70% of PIL using prospective consent, withdrawal was described in generic terms leaving patients unaware of the difference between stopping treatment and all trial involvement. Nineteen (38%) trials offered withdrawing patients the option to delete existing data.

CONCLUSIONS

Withdrawal and retention is poorly described within PIL and addressing this might positively impact levels of patient attrition, reducing missing data. Consent information is unbalanced, focussing on patient's rights to withdraw without accompanying information that promotes robust consent and sustained participation. With many citing altruistic reasons for participation it is essential that PIL include more information on retention and clarify withdrawal terminology so patients are aware of how they can make a valuable contribution to clinical studies. There is a need to determine how retention can be described to patients to avoid concerns of coercion. Future research is needed to explore whether the absence of information about retention at the time of consent is impacting attrition.