Systematic review of conceptual and theoretical frameworks used in palliative care and end-of-life care research studies.

Background: Frameworks are the conceptual underpinnings of the study. Both conceptual and theoretical frameworks are often used in palliative and end-of-life care studies to help with study design, guide, and conduct investigations. While an increasing number of investigators have included frameworks in their study, to date, there has not been a comprehensive review of frameworks that were utilized in palliative and end-of-life care research studies.

Aim: To summarize conceptual and theoretical frameworks used in palliative and end-of-life care research studies. And to synthesize which of eight domains from the National Consensus Project's Clinical Practice Guidelines for Quality Palliative Care (fourth edition) each framework belongs to.

Design: Systematic review.

Data Sources: Four electronic databases (EMBASE, the Cumulative Index to Nursing and Allied Health, PsychINFO, and PubMed) were searched from July 2010 to September 2021.

Results: A total 2231 citations were retrieved, of which 44 articles met eligibility. Across primary studies, 33,801 study participants were captured. Twenty-six investigators (59.1%) proposed previously unpublished frameworks. In 10 studies, investigators modified existing frameworks, mainly to overcome inherent limitations. In eight studies, investigators utilized existing frameworks referenced in previously published studies. There were eight orientations identified among 44 frameworks we reviewed (e.g. system, patient, patient-doctor).

Conclusions: We examined palliative and end-of-life research studies to identify and characterize conceptual or theoretical frameworks proposed or utilized. Of 44 frameworks we reviewed, 21 studies (47.7%) were aligned with a Clinical Practice Guideline's single domain, while the rest two or more of eight guidelines in quality palliative care domains.