Neurological sciences based on evidence

OBJECTIVE: An exhaustive search of reported metanalysis from any medical speciality is described. MATERIAL AND METHODS: Search of papers included in MEDLINE or EMBASE between 1973-1998. A descriptive analysis of the reported papers (frequency tables and graphics) is described, including differences of mean of reported metanalysis papers by medical speciality and year. RESULTS: 1,514 papers were selected and classified. Between 1977-1987 overall mean of reported studies of neurologic metanalysis (1.20 +/- 1.10) was significatively inferior to the 1988-1998 (11.20 +/- 7.85) (p < 0.001). Global number of neurologic metanalysis was positively correlated (p < 0.05) with the number of studies about fundamentals and methodology during the study period. CONCLUSIONS: A progressive increase in the number of reported neurologic metanalysis since 1977 can be demonstrated. Diffusion of knowledge about fundamentals and methodology of metanalysis seems to have drawn and increase in performing and reporting this kind of analysis.