Patient and carer experiences of living with multiple myeloma and myelodysplastic syndrome.

OBJECTIVE: Multiple myeloma (MM) and myelodysplastic syndrome (MDS) are treatable but incurable conditions that can substantially impact the daily lives of people living with these conditions and their carers. We sought to understand the experience of people living with and carers affected by these conditions in Tasmania, a regional area of Australia. METHODS: Exploratory qualitative study. People living with MM or MDS or their carers in Southern Tasmania were recruited by a haematology nurse and invited to participate in focus groups. Data collection was by groups held online and face-to-face in 2022. Thematic analysis was used. RESULTS: Ten groups were held with 48 participants (n = 23 with MM, n = 9 with MDS, n = 16 carers). Key themes arising from focus groups with people living with MM/MDS were (1) Relationships and Support; (2) Positive Attitude; (3) Perception of Condition; and (4) Symptoms and Comorbidities. Some people with MM/MDS had to take on a caring role for their carer due to carer illness. Key themes arising from carer focus groups included (1) Supportive Relationships; (2) Accommodating Change; and (3) Own Needs. Not all carers viewed their caring role as burdensome. CONCLUSION: Future work should consider what supports are required for patients acting as carers, and carer burden should not be assumed.

The impact of regular, low-dose, sustained-release morphine for chronic breathlessness on caregiver burden: An exploratory analysis of the BEAMS trial.

BACKGROUND: Chronic breathlessness adversely impacts people with chronic obstructive pulmonary disease and their caregivers (family and friends), who may, in turn, experience significant burden due to their caregiving role. Sustained-release morphine may reduce chronic breathlessness in some patients, which may have an impact on caregivers' perceived burden. AIM: To explore the impact on caregiver burden of active treatment of people with chronic breathlessness (modified Medical Research Council (mMRC) ⩾ 3) and chronic obstructive pulmonary disease (COPD) with regular, low-dose, sustained-release morphine within a multi-site, double-blind, randomised, placebo-controlled trial. DESIGN: Exploratory analysis of self-reported caregiver burden at baseline and end of week 3 in a randomised, double-blind, placebo-controlled study. Caregiver measures included: demographics and perceived burden (Zarit Burden Interview 12-item short-form questionnaire). Patient measures included: worst breathlessness and FitBitR-measures. SETTING/PARTICIPANTS: All consenting caregivers of trial patient participants in a multi-site study recruiting from palliative care and respiratory services. RESULTS: Caregivers (n = 49; 59% women; median age 68 years [IQR 50-75]) reported median baseline caregiver burden 12 [IQR 5-17], with 53% reporting high burden (⩾13). Eighty-four percent of caregivers reported no change in burden. In people whose worst breathlessness improved, caregiver burden moved in the same direction, though the correlation was not significant (rs = 0.25, p = 0.17). Conversely, caregiver burden worsened as patients' minutes lightly active increased, with the correlation being significant (rs = 0.56, p = 0.04). CONCLUSIONS: Caregivers reported high levels of caregiver burden, but patients' response to treatment in terms of their symptom and function may influence change in caregiver burden over a three-week period.

[Special issue PRO] A demonstration of estimands and sensitivity analyses for time-to-deterioration of patient reported outcomes.

In oncology trials, health-related quality of life (HRQoL), specifically patient-reported symptom burden and functional status, can support the interpretation of survival endpoints, such as progression-free survival. However, applying time-to-event endpoints to patient-reported outcomes (PRO) data is challenging. For example, in time-to-deterioration analyses clinical events such as disease progression are common in many settings and are often handled through censoring the patient at the time of occurrence; however, disease progression and HRQoL are often related leading to informative censoring. Special consideration to the definition of events and intercurrent events (ICEs) is necessary. In this work, we demonstrate time-to-deterioration of PRO estimands and sensitivity analyses to answer research questions using composite, hypothetical, and treatment policy strategies applied to a single endpoint of disease-related symptoms. Multiple imputation methods under both the missing-at-random and missing-not-at-random assumptions are used as sensitivity analyses of primary estimands. Hazard ratios ranged from 0.52 to 0.66 over all the estimands and sensitivity analyses modeling a robust treatment effect favoring the treatment in time to disease symptom deterioration or death. Differences in the estimands include how people who experience disease progression or discontinue the randomized treatment due to AEs are accounted for in the analysis. We use the estimand framework to define interpretable and principled approaches for different time-to-deterioration research questions and provide practical recommendations. Reporting the proportions of patient events and patient censoring by reason helps understand the mechanisms that drive the results, allowing for optimal interpretation.

[Special issue PRO] Considering endpoints for comparative tolerability of cancer treatments using patient report given the estimand framework.

Regulatory agencies are advancing the use of systematic approaches to collect patient experience data, including patient-reported outcomes (PROs), in cancer clinical trials to inform regulatory decision-making. Due in part to clinician under-reporting of symptomatic adverse events, there is a growing recognition that evaluation of cancer treatment tolerability should include the patient experience, both in terms of the overall side effect impact and symptomatic adverse events. Methodologies around implementation, analysis, and interpretation of "patient" reported tolerability are under development, and current approaches are largely descriptive. There is robust guidance for use of PROs as efficacy endpoints to compare cancer treatments, but it is unclear to what extent this can be relied-upon to develop tolerability endpoints. An important consideration when developing endpoints to compare tolerability between treatments is the linkage of trial design, objectives, and statistical analysis. Despite interest in and frequent collection of PRO data in oncology trials, heterogeneity in analyses and unclear PRO objectives mean that design, objectives, and analysis may not be aligned, posing substantial challenges for the interpretation of results. The recent ICH E9 (R1) estimand framework represents an opportunity to help address these challenges. Efforts to apply the estimand framework in the context of PROs have primarily focused on efficacy outcomes. In this paper, we discuss considerations for comparing the patient-reported tolerability of different treatments in an oncology trial context.

International Society for Quality of Life Research commentary on the US Food and Drug Administration draft guidance for industry on core patient-reported outcomes in cancer clinical trials.

In June 2021, the US Food and Drug Administration (FDA) released a draft guidance for industry on core patient-reported outcomes (PROs) and related considerations for instrument selection and trial design in registrational cancer clinical trials, building on prior communications about the use of PROs to assess efficacy and tolerability in oncology drug development. The International Society for Quality of Life Research (ISOQOL) Standards and Best Practices Committee led an initiative to draft a commentary about the guidance, focusing on its positive aspects and areas that would benefit from additional clarification and consideration. For comprehensiveness, the authors reviewed existing public comments on the draft guidance, and the commentary underwent a thorough review process through three ISOQOL Special Interest Groups (Psychometrics, Clinical Practice, and Regulatory and Health Technology Assessment Engagement) followed by the ISOQOL Board. The goal of this commentary is to situate this new and relevant guidance document within the context of recent regulatory efforts on PROs and highlight areas in which further work may ultimately benefit the field.

The potential impact of proxy reports for symptom experience and care quality and experience in advanced cancer.

OBJECTIVES: As the US tests models of care for the seriously ill, patient perceptions of the quality of care are important. Proxies are often needed for this group. We sought to understand the potential impact of proxy reports for the assessment of care quality and experience in cancer. METHODS: Secondary data analysis of a deidentified prospective study that included surveys of perceived care quality, including symptom management, from patients with advanced cancer receiving chemotherapy and their caregivers. Surveys were administered at diagnosis (time 1) and treatment (time 2), with top-box scoring used for analysis. Overall concordance was assessed using metrics including Gwet's AC1. The proportion of the highest scores by respondent type within 2 subgroups were examined: (1) symptom burden and (2) practice setting. RESULTS: Data from 83 dyads were analyzed. Proxies and patients frequently reported the highest scores for quality (time 1: proxies: 77% and patients: 80%). At time 1, 14% of proxies and 10% of patients reported an unmet need for symptom palliation. Most patients reporting an unmet need gave the top score for quality (75%), but fewer proxies did so (45%). Proxy and patient reports were similar within practice settings. Concordance was at least moderate (nearly all outcomes >0.5 and some >0.8) by Gwet's AC1. SIGNIFICANCE OF RESULTS: Findings of at least moderate concordance and similar experience outcomes within subgroups suggest the use of proxies may not change estimates substantially. However, consideration should be taken when evaluating symptom management, particularly if such evaluations inform assessment of provider performance.

Time to deterioration of symptoms or function using patient-reported outcomes in cancer trials.

Time-to-event endpoints for patient-reported outcomes, such as time to deterioration of symptoms or function, are frequently used in cancer clinical trials. Although time-to-deterioration endpoints might seem familiar to cancer researchers for being similar to survival or disease-progression endpoints, there are unique considerations associated with their use. The complexity of time-to-deterioration endpoints should be weighed against the information that they add to the tumour, survival, and safety data used to inform the risks and benefits of an investigational drug. Here we use the estimand framework to show how analytical decisions answer different clinical questions of interest, some of which might be uninformative. Challenges including the consideration of intercurrent events, the difficulty in maintaining adequate completion rates, and considerable patient and trial burden from long-term, serial, patient-reported outcome measurements render time to deterioration a problematic approach for widespread use. For trials in which a comparative benefit in symptoms or function is an objective, an analysis at pre-specified relevant timepoints could be a better approach.

An Exploratory Analysis of the "Was It Worth It?" Questionnaire as a Novel Metric to Capture Patient Perceptions of Cancer Treatment.

OBJECTIVES: Asking "Was it worth it?" (WIWI) potentially captures the patient perception of a treatment's benefit weighed against its harms. This exploratory analysis evaluates the WIWI questionnaire as a metric of patients' perspectives on the worthwhileness of cancer treatment. METHODS: A 3-item WIWI questionnaire was assessed at end of treatment in patients with cancer on the COMET-2 trial (NCT01522443). WIWI items were evaluated to determine their association with quality of life (QOL), treatment duration, end-of-treatment reason, patient-reported adverse events (AEs), and disease response. RESULTS: A total of 65 patients completed the questionnaire; 40 (62%), 16 (25%), and 9 (14%) patients replied yes, uncertain, and no to "Was it worthwhile for you to receive the cancer treatment given in this study?" (item 1), respectively; 39 (60%), 12 (18%), and 14 (22%) to "If you had to do it over again, would you choose to have this cancer treatment?"; and 40 (62%), 14 (22%), and 11 (17%) to "Would you recommend this cancer treatment to others?" Patients responding yes to item 1 remained on treatment longer than those responding uncertain or no (mean 23.0 vs 11.3 weeks, P<.001). Patients responding uncertain/no to item 1 discontinued treatment because of AEs more frequently than those responding yes (36% vs 7.5%, P=.004) and demonstrated meaningful decline in QOL from baseline (-2.5 vs -0.2 mean change, P<.001). Associations between WIWI responses and most patient-reported AEs or treatment efficacy did not reach statistical significance. CONCLUSIONS: Patients who responded affirmatively on WIWI items remained on therapy longer, were less likely to stop treatment because of AEs, and demonstrated superior QOL. The WIWI may inform clinical practice, oncology research, and value frameworks.

How Useful Are Digital Health Terms for Outcomes Research? An ISPOR Special Interest Group Report.

OBJECTIVES: This study aimed to review definitions of digital health and understand their relevance for health outcomes research. Four umbrella terms (digital health, electronic health, mobile health, and telehealth/telemedicine) were summarized in this article. METHODS: PubMed/MEDLINE, Embase, Cochrane Library, and EconLit were searched from January 2015 to May 2020 for systematic reviews containing key Medical Subject Headings terms for digital health (n = 38) and synonyms of "definition." Independent pairs of reviewers performed each stage of the review, with reconciliation by a third reviewer if required. A single reviewer consolidated each definition for consistency. We performed text analysis via word clouds and computed document frequency-and inverse corpus frequency scores. RESULTS: The search retrieved 2610 records with 545 articles (20.9%) taken forward for full-text review. Of these, 39.3% (214 of 545) were eligible for data extraction, of which 134 full-text articles were retained for this analysis containing 142 unique definitions of umbrella terms (digital health [n = 4], electronic health [n = 36], mobile health [n = 50], and telehealth/telemedicine [n = 52]). Seminal definitions exist but have increasingly been adapted over time and new definitions were created. Nevertheless, the most characteristic words extracted from the definitions via the text analyses still showed considerable overlap between the 4 umbrella terms. CONCLUSIONS: To focus evidence summaries for outcomes research purposes, umbrella terms should be accompanied by Medical Subject Headings terms reflecting population, intervention, comparator, outcome, timing, and setting. Ultimately a functional classification system is needed to create standardized terminology for digital health interventions denoting the domains of patient-level effects and outcomes.

The use of proxies and proxy-reported measures: a report of the international society for quality of life research (ISOQOL) proxy task force.

AIMS: Proxy reports are often used when patients are unable to self-report. It is unclear how proxy measures are currently in use in adult health care and research settings. We aimed to describe how proxy reports are used in these settings, including the use of measures developed specifically for proxy reporting in adult health populations. METHODS: We systematically searched Medline, PsycINFO, PsycTESTS, CINAHL and EMBASE from database inception to February 2018. Search terms included a combination of terms for quality of life and health outcomes, proxy-reporters, and health condition terms. The data extracted included clinical context, the name of the proxy measure(s) used and other descriptive data. We determined whether the measures were developed specifically for proxy use or were existing measures adapted for proxy use. RESULTS: The database search identified 17,677 possible articles, from which 14,098 abstracts were reviewed. Of these, 11,763 were excluded and 2335 articles were reviewed in full, with 880 included for data extraction. The most common clinical settings were dementia (30%), geriatrics (15%) and cancer (13%). A majority of articles (51%) were paired studies with proxy and patient responses for the same person on the same measure. Most paired studies (77%) were concordance studies comparing patient and proxy responses on these measures. DISCUSSION: Most published research using proxies has focused on proxy-patient concordance. Relatively few measures used in research with proxies were specifically developed for proxy use. Future work is needed to examine the performance of measures specifically developed for proxies. SYSTEMATIC REVIEW REGISTRATION: PROSPERO No. CRD42018103179.

Assessment of patient perception of treatment assignment and patient-reported outcomes in a cannabis use disorder trial.

Background: Blinding is a cornerstone of trial methodology. Prior work indicates participant-perceived assignment may be associated with trial outcomes. Less is known about how perception changes over time and if this is associated with outcomes.Objectives: To evaluate if participants change their perception of assignment over time in a blinded trial, and if perception is associated with different types of patient-reported outcomes (PROs).Methods: This was a secondary analysis of data from the Achieving Cannabis Cessation-Evaluating N-Acetylcysteine Treatment (ACCENT) trial, which evaluated the efficacy of N-acetylcysteine (NAC) relative to placebo for treating cannabis use disorder. Participants (N = 234; 164 men, 70 women) were asked at weeks 5 and 9 what treatment (placebo or NAC) they believed they were receiving. We included PROs proximal (cannabis-associated problems, craving) and distal (anxiety) to the intervention. Analysis was by multiple linear regression and mixed models.Results: Approximately 20% of participants in both arms changed their perception over time. Relative to participants who consistently perceived assignment to placebo, participants who consistently perceived assignment to NAC did not always have comparatively better average scores (coefficient -3.3 [95% CI: -7.0, 0.5]). In some analyses, participants who switched to guessing NAC from placebo had comparatively better average scores (coefficient -3.0 [95% CI: -9.3, 3.4]), but this was inconsistent across outcomes or strata defined by actual assignment or guess accuracy.Conclusion: The study suggests that the proportion of individuals who switch their perception over time is modest. However, this group may influence the estimates of intervention effects on some PROs.

Ethical Considerations for the Inclusion of Patient-Reported Outcomes in Clinical Research: The PRO Ethics Guidelines.

Importance: Patient-reported outcomes (PROs) can inform health care decisions, regulatory decisions, and health care policy. They also can be used for audit/benchmarking and monitoring symptoms to provide timely care tailored to individual needs. However, several ethical issues have been raised in relation to PRO use. Objective: To develop international, consensus-based, PRO-specific ethical guidelines for clinical research. Evidence Review: The PRO ethics guidelines were developed following the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network's guideline development framework. This included a systematic review of the ethical implications of PROs in clinical research. The databases MEDLINE (Ovid), Embase, AMED, and CINAHL were searched from inception until March 2020. The keywords patient reported outcome* and ethic* were used to search the databases. Two reviewers independently conducted title and abstract screening before full-text screening to determine eligibility. The review was supplemented by the SPIRIT-PRO Extension recommendations for trial protocol. Subsequently, a 2-round international Delphi process (n = 96 participants; May and August 2021) and a consensus meeting (n = 25 international participants; October 2021) were held. Prior to voting, consensus meeting participants were provided with a summary of the Delphi process results and information on whether the items aligned with existing ethical guidance. Findings: Twenty-three items were considered in the first round of the Delphi process: 6 relevant candidate items from the systematic review and 17 additional items drawn from the SPIRIT-PRO Extension. Ninety-six international participants voted on the relevant importance of each item for inclusion in ethical guidelines and 12 additional items were recommended for inclusion in round 2 of the Delphi (35 items in total). Fourteen items were recommended for inclusion at the consensus meeting (n = 25 participants). The final wording of the PRO ethical guidelines was agreed on by consensus meeting participants with input from 6 additional individuals. Included items focused on PRO-specific ethical issues relating to research rationale, objectives, eligibility requirements, PRO concepts and domains, PRO assessment schedules, sample size, PRO data monitoring, barriers to PRO completion, participant acceptability and burden, administration of PRO questionnaires for participants who are unable to self-report PRO data, input on PRO strategy by patient partners or members of the public, avoiding missing data, and dissemination plans. Conclusions and Relevance: The PRO ethics guidelines provide recommendations for ethical issues that should be addressed in PRO clinical research. Addressing ethical issues of PRO clinical research has the potential to ensure high-quality PRO data while minimizing participant risk, burden, and harm and protecting participant and researcher welfare.

Does Knowledge of Treatment Assignment Affect Patient Report of Symptoms, Function, and Health Status? An Evaluation Using Multiple Myeloma Trials.

OBJECTIVES: Unblinded trials are common in oncology, but patient knowledge of treatment assignment may bias response to questionnaires. We sought to ascertain the extent of possible bias arising from patient knowledge of treatment assignment. METHODS: This is a retrospective analysis of data from 2 randomized trials in multiple myeloma, 1 double-blind and 1 open label. We compared changes in patient reports of symptoms, function, and health status from prerandomization (screening) to baseline (pretreatment but postrandomization) across control and investigational arms in the 2 trials. Changes from prerandomization scores at ~2 and 6 months on treatment were evaluated only across control arms to avoid comparisons between 2 different experimental drugs. All scores were on 0- to 100-point scales. Inverse probability weighting, entropy balancing, and multiple imputation using propensity score splines were used to compare score changes across similar groups of patients. RESULTS: Minimal changes from screening were seen at baseline in all arms. In the control arm, mean changes of <7 points were seen for all domains at 2 and 6 months. The effect of unblinding at 6 months in social function was a decline of less than 6 points (weighting: -3.09; 95% confidence interval -8.41 to 2.23; balancing: -4.55; 95% confidence interval -9.86 to 0.76; imputation: -5.34; 95% confidence interval -10.64 to -0.04). CONCLUSION: In this analysis, we did not find evidence to suggest that there was a meaningful differential effect on how patients reported their symptoms, function or health status after knowing their treatment assignment.

The estimand framework and its application in substance use disorder clinical trials: a case study.

Relapse rates among individuals with substance use disorder (SUD) remain high and new treatment approaches are needed, which require evaluation in randomized controlled trials (RCTs). Measurement and interpretation challenges for SUD RCT data are often ignored or presented only in statistical analysis plans. Since different analytic approaches may result in different estimates and thus interpretations of the treatment effect, it is important to present this clearly throughout the trial. Inconsistencies between study analyses and objectives present further challenges for interpretation and cross-study comparisons. The recent International Council for Harmonization (ICH) addendum provides standardized language and a common framework for aligning trial objectives, design, conduct, and analysis. The framework focuses on estimands, which describe the treatment effect and link the trial objective with the scientific question and the analytic approach. The use of estimands offers SUD researchers and clinicians the opportunity to explicitly address events that affect measurement and interpretation at the outset of the trial. Furthermore, the use of standard terminology can lead to clearer interpretations of SUD trials and the treatments evaluated in SUD trials. Resources for understanding and applying estimands are needed to optimize the use of this new, helpful framework. This Perspective provides this resource for SUD researchers. Specifically, it highlights the relevance of estimands for SUD trials. Furthermore, it demonstrates how estimands can be used to develop clinically relevant analyses to address challenges in SUD trials. It also shows how a standardized framework can be employed to improve the interpretation and presentation of SUD study findings.

Patient and proxy reports regarding the experience of treatment decision-making in cancer care.

OBJECTIVE: Shared decision-making, including the elicitation of patient preferences regarding treatment decisions, is considered part of high-quality cancer care. However, patients may not be able to self-report due to illness, and therefore proxy reports may be used. We sought to determine the difference between proxy and patient reports about patient decisions and preferences among patients who received or were scheduled for chemotherapy using data from a large, population-based survey of patients with incident lung or colorectal cancer. METHODS: Of 3573 patients who received or were scheduled for chemotherapy, 3108 self-reported and 465 had proxies reporting on their behalf about preferred and actual decision roles regarding this treatment. Preferred and actual decision roles were assessed using the Control Preferences Scale, and categorized as shared, patient-controlled, or doctor-controlled. Multivariable logistic regression models were used to assess the association between patient and proxy responses and whether preferences were met. The models adjusted for sociodemographic and clinical variables and patient/proxy-reported health status. RESULTS: Sixty-three percent of all respondents reported actual roles in decisions that matched their preferred roles (role attainment). Proxies and patients were similarly likely to report role attainment (65% vs 63%). In adjusted analyses, proxies were more likely report role attainment (OR = 1.27, 95%CI = 1.02-1.59), but this difference was smaller if health variables were excluded from the model (OR = 1.14, 95%CI = 0.92-1.41). CONCLUSION: Most patients' preferences for treatment participation were met. Surveys from proxies appear to yield small differences on the reports of attainment of preferred treatment decision-making roles in cancer care vs surveys from patients.

Exploration of baseline patient-reported side effect bother from cancer therapy.

BACKGROUND: Patient reports of expected treatment side effects are increasingly collected as part of the assessment of patient experience in clinical trials. A global side effect item that is patient-reported has the potential to inform overall tolerability. Therefore, the aim of this study was to examine the completion and distribution of such a global single-item measure of side effect burden in five cancer clinical trials. METHODS: Data from five trials from internal Food and Drug Administration databases that included the Functional Assessment of Cancer Therapy-General single-item measure of overall side effect burden (i.e. impact on degree of bother) were analyzed. Completion rates for the side effect bother item, items adjacent to this item, and two non-adjacent items on the Functional Assessment of Cancer Therapy-General that are related to health-related quality of life were calculated at the baseline assessment and at the 3-month assessment. To evaluate the distribution, the percentage of patients reporting high levels (quite a bit or very much bother) of side effect bother at baseline and 3 months was assessed. RESULTS: Completion rates for all items were at least 80% regardless of time point or trial population. However, in three of the five trials, completion rates for the side effect bother item were lower at baseline compared to adjacent and non-adjacent items. This difference was not observed at 3 months. Up to 9.4% of patients reported high levels of side effect bother at baseline. CONCLUSION: Patients may enter trials already reporting some bother from side effects. This can make interpretation of results with respect to the investigational agent under study challenging. Patients may skip an item evaluating side effect bother at baseline, suggesting some difficulty with interpretation of what is being asked. Further study of the wording and utility of a baseline side effect bother assessment is warranted.

US Food and Drug Administration review of statistical analysis of patient-reported outcomes in lung cancer clinical trials approved between January, 2008, and December, 2017.

With the advent of patient-focused drug development, the US Food and Drug Administration (FDA) has redoubled its efforts to review patient-reported outcome (PRO) data in cancer trials submitted as part of a drug's marketing application. This Review aims to characterise the statistical analysis of PRO data from pivotal lung cancer trials submitted to support FDA drug approval between January, 2008, and December, 2017. For each trial and PRO instrument identified, we evaluated prespecified PRO concepts, statistical analysis, missing data and sensitivity analysis, instrument completion, and clinical relevance. Of the 37 pivotal lung cancer trials used to support FDA drug approval, 25 (68%) trials included PRO measures. The most common prespecified PRO concepts were cough, dyspnoea, and chest pain. At the trial level, the most common statistical analyses were descriptive (24 trials [96%]), followed by time-to-event analyses (19 trials [76%]), longitudinal analyses (12 trials [48%]), and basic inferential tests or general linear models (10 trials [40%]). Our findings indicate a wide variation in the analytic techniques and data presentation methods used, with very few trials reporting clear PRO research objectives and sensitivity analyses for PRO results. Our work further supports the need for focused research objectives to justify and to guide the analytic strategy of PROs to facilitate the interpretation of patient experience.

Analyzing patient-reported outcome data when completion differs between arms in open-label trials: an application of principal stratification.

PURPOSE: Cancer trials are often open-label and include patient-reported outcomes (PROs). Previous work has demonstrated that patients may complete PRO assessments less frequently in the control arm compared with the experimental arm in open-label trials. Such differential completion may affect PRO results. This paper sought to explore principal stratification methodology to address potential bias caused by the posttreatment intermediate variable of questionnaire completion. METHODS: We evaluated six randomized trials (five open-label and one double-blind) of anticancer therapies with varying levels of PRO completion submitted to the Food and Drug Administration (FDA). We applied complete case analysis (CCA), multiple imputation (MI), and principal stratification to evaluate PRO results for quality of life (QOL) and the domains of physical, role, and emotional function (PF, RF, and EF). Assignment to potential principal strata was by the expectation maximization algorithm using patient baseline characteristics. RESULTS: Completion rates in the experimental arm ranged from 66% to 94% and 51% to 95% in the control arm. Four trials had negligible completion differences between arms (1%-2%), and two had large differences favoring the experimental arm (15%-17%). For trials with negligible completion differences, principal stratification results were similar to CCA and MI results for all domains. Notable differences in point estimates may be observed in trials with large differences in completion rates. However, in the examined trials, the confidence intervals for the principal stratification estimates overlapped with the ones obtained using CCA. CONCLUSIONS: The principal stratification estimand may be a useful additional analysis, especially if PRO completion differs between arms.

Trials with proxy-reported outcomes registered on the Australian New Zealand Clinical Trials Registry (ANZCTR).

AIMS: A proxy is someone other than a patient who reports a patient's outcomes as if they are the patient. Due to known discordance with patient reports, proxies are often not recommended in clinical trials; however, proxies may be needed in certain research contexts. We aimed to identify and describe trials registered on the Australian New Zealand Clinical Trials Registry (ANZCTR) with proxy-reported endpoints. METHODS: ANZCTR was systematically searched from inception (2005) to 31 March 2017 for trials with proxy-reported endpoints. Primary and secondary endpoints for each trial retrieved by the search were individually coded (proxy-reported: yes/no), and trials with confirmed proxy-reported endpoints were included in the analysis. RESULTS: Of 13,666 registered trials, 469 (3.4%) included a proxy-reported endpoint (867 individual proxy-reported endpoints in total: 62% family member proxy, 22% health professional). Proxy endpoint inclusion did not significantly increase over time (r = 0.18, p = 0.59). Mental health (11.5%), stroke (10.3%) and neurological (8.3%) trials had the highest proportion of trials using proxies. Of the 469 trials, 123 (26.2%) studies involved paediatric patients. DISCUSSION: Proxy-reported endpoints are included in a small but notable number of studies, which may indicate other types of outcomes are used for patients unable to self-report, or that these patients are under-researched.