Methodological issues in a before-after study design to evaluate the Liverpool Care Pathway for the Dying Patientin hospital.

摘要

BACKGROUND: In 2006, as the first step of a 3-year research programme to assess the Liverpool Care Pathway for the Dying Patient (LCP) in hospital, the original LCP documentation was translated and piloted in four Italian hospital wards in Genoa. The primary aim was to evaluate the feasibility of LCP implementation in the Italian context. The secondary aim of the study was to evaluate the effectiveness of the LCP with an uncontrolled before-after design. AIM: The aim of the study was to discuss and critically evaluate the methodological issues in designing and interpreting the results of the before-after study design. SETTING/PARTICIPANTS: All cancer deaths which occurred in four hospital wards (three general medicine and one respiratory disease) 4 months before and 4 months after LCP implementation (2 months for the respiratory disease ward) were registered. Caregivers were interviewed after the patient's death using the Toolkit After-Death Bereaved Family Member Interview. RESULTS: A total of 111 cancer deaths were identified (63 before and 48 after) and 79 caregivers (71.2%) were interviewed (46 before and 33 after). The analyses on number and characteristics of the patients, interviewed caregivers, compliance and modality of assessment showed significant differences before and after. A remarkable internal correlation coefficient for all of the Toolkit scales within the four hospital wards was observed. CONCLUSIONS: This analysis confirms the high risk of selection and information bias inherent the uncontrolled before- after study design. The high internal correlation strongly suggests that clustering should be taken into account in this kind of study.