How far along the disease trajectory? An examination of the time-related patient characteristics in the palliative oncology literature

Abstract

Purpose Adequate reporting of time-related patient characteristics is needed for research findings to be properly interpreted, applied and reproduced. Our objective was to characterize the time-related patient characteristics in palliative oncology studies and to examine the differences in time-related patient characteristics by various study characteristics. Methods We extracted time-related patient characteristics including actual survival, performance status, cancer stage, disease trajectory, study setting and eligibility criteria (life expectancy and performance status) from an established cohort of original palliative oncology articles published in 2004 and 2009. Results Among 742 original articles, 409 (55%) were case series. Only 247 (33%) articles reported actual survival, 157 (21%) reported actual performance status, 362 (49%) cancer stage, and 392 (53%) reported study setting. Based on all the available time-related characteristics, we were able to classify the studies into specific time-related categories in 378 (51%) studies. Among these, only 47 (13%) focused on patients in the last month of life. Compared to studies involving patients earlier in the disease trajectory, these studies were more likely to be case series (81% vs. 56%, P=0.005), retrospective (64% vs. 49%, P=0.03), and had a smaller sample size (median 20 vs. 61, P=0.06). Conclusions A majority of studies did not adequately report time-related patient characteristics. We also identified a gap in both the quantity and quality of studies involving patients in the last month of life. Our study has implications for study reporting and future directions for palliative oncology research.

Factors Associated With Attrition in a Multicenter Longitudinal Observational Study of Patients With Advanced Cancer

“…Because palliative care studies by nature often enroll patients who have a poorer performance status and are more symptomatic, it should be expected that patients have a higher rate of dropout. Our study explains why there are few prospective studies involving patients in the last weeks of life (29) and investigating prevalent symptoms at the end-of-life such as delirium (30). This group of patients often has high level of distress and carefully designed studies are needed to improve their care while minimizing attrition.…”

“…At the patient selection level, including patients with higher KPS, lower symptom burden and no cognitive failure, could be associated with decreased attrition rates. However, using these criteria affects patient selection, raising some issues with the generalizability of findings, given that patients with worse performance status and shorter survival are often excluded from research (29). To address this issue, shortening the follow-up time and increasing the recruitment of patients with increased symptom burden or lower functional status would be plausible solutions.…”

Integration of oncology and palliative care: a Lancet Oncology Commission

“…17 Patients with survival of >6 months, 4-6 months and less than 3 months to live each constituted approximately 1/3 of studies; however, patients with longer survival (>12 months) and very short survival (<1 month) were under-represented. 542 Only 6% of studies were randomized controlled trials, with low quality of reporting. 139 Thus, there remain significant opportunities to improve both the quantity and quality of palliative oncology studies.…”

Quality of Life Trends in People With and Without Cancer Referred to Volunteer-Provided Palliative Care Services (ELSA): A Longitudinal Study

“…48 Prospective studies are less common, especially for those referred to nonclinical services. 49 This study adds to knowledge by reporting longitudinal, prospectively collected, quality of life data, of those expected to be in their last year of life who were referred to volunteer-provided palliative care services.…”