Truth survival in clinical research: an evidence-based requiem?

PURPOSE

Factors associated with the survival of truth of clinical conclusions in the medical literature are unknown. The authors hypothesized that conclusions derived from studies using better methodology should have a longer half-life.

DATA SOURCES

MEDLINE and hand searches of journals with studies on cirrhosis and hepatitis.

STUDY SELECTION

Original articles and meta-analyses published from 1945 to 1999 about cirrhosis or hepatitis in adults.

DATA SYNTHESIS

In 2000, 285 of 474 conclusions (60%) were still considered to be true, 91 (19%) were considered to be obsolete, and 98 (21%) were considered to be false. The half-life of truth was 45 years. The 20-year survival of conclusions derived from meta-analysis was lower (57% +/- 10%) than that from nonrandomized studies (87% +/- 2%) (P < 0.001) or randomized trials (85% +/- 3%) (P < 0.001). The survival of conclusions was not different when studies of high methodologic quality were compared with those of low quality. In randomized trials, the 50-year survival rate was higher for 52 negative conclusions (68% +/- 13%) than for 118 positive conclusions (14% +/- 4%) (P < 0.001).

CONCLUSIONS

Contrary to the authors' hypothesis, conclusions based on recognized, good methodology had no clear survival advantage. To better convince clinicians of the long-term utility of evidence-based medicine, better prognostic factors should be developed.