The evidence base of palliative medicine: is inpatient palliative medicine evidence-based?

Abstract

Background: In 2001, Good and Stafford published a study attempting to show that inpatient palliative medicine is evidence-based. Aim: To critically examine the papers cited in support of the claim that palliative medicine is evidence-based. Method: All the papers cited were re-examined by at least two reviewers. The papers were graded using a tool used in the production of 22 evidence-based national clinical guidelines over the past three years. Differences of opinion about quality were resolved by discussion or independent arbitration. Results: The 41 papers cited by Good and Stafford included 25 randomized controlled trials (RCT), six other controlled studies and 10 uncontrolled studies. Sample size. Mean sample size was 160 (range 9—1404). The median sample size was 56; 19/41(46%) had <50 subjects; 30/41 (73%) had <100. Power calculations. 16/25 (64%) of RCTs, had no power calculations, making it difficult to draw conclusions about true differences between groups. Quality rating and grade of evidence: Of the RCTs 15/25 (60%) had a high risk of bias; of the other controlled studies 5/6 (83%) had a high risk of bias. Applicability. The studies were generally applicable to a population with advanced disease: 30/41 (73%) related with populations with advanced disease. Conclusions: This study demonstrates that studies cited in support of palliative medicine as an evidence-based specialty are of variable, and at times poor quality. This study seems to show that the claim that inpatient palliative medicine is evidence-based is at best tenuous and at worst misleading. Palliative Medicine 2007; 21 : 623—627