Systematic review and meta-analysis of information source usage: do medical specialists use the best evidence for clinical decision-making?

OBJECTIVES: To examine which information sources medical specialists use to answer clinical questions in daily practice and to describe the relative frequency of use for each source. DESIGN: Systematic review with narrative synthesis and meta-analysis. DATA SOURCES: Academic Search Premier, APA PsycINFO, CINAHL, Emcare, Cochrane Library, Web of Science, Embase and PubMed were searched for relevant studies published from 2000 to 1 June 2025. ELIGIBILITY CRITERIA: We included peer-reviewed English-language studies reporting on the frequency of information source usage by medical specialists when addressing clinical questions. Studies reporting usage on a continuous (0-100%) scale were eligible for meta-analysis. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently screened studies. Data were extracted by one reviewer and checked by a second. Study quality was assessed using the Quality Assessment tool with Diverse Studies tool. A narrative synthesis was conducted for studies that were not eligible for quantitative pooling to summarise patterns in information-seeking behaviour and reported barriers. A random-effects meta-analysis was performed for studies reporting continuous usage percentages and assessing at least four information sources. Sensitivity analyses were conducted using a leave-one-out approach. Potential publication bias was explored descriptively using funnel plots. RESULTS: 25 studies were included, of which 6 (with 8641 participants) were eligible for meta-analysis. The narrative synthesis of non-pooled studies showed a consistent reliance on standalone information sources and identified barriers to the use of aggregated sources. In the meta-analysis, digital databases such as PubMed were the most frequently used information source (74%, 95% CI 63% to 85%), followed by textbooks (71%, 95% CI 57% to 85%) and consultation with colleagues (43%, 95% CI 15% to 71%). Systematically aggregated sources, including clinical practice guidelines (38%, 95% CI 27% to 49%) and point-of-care websites (49%, 95% CI 17% to 81%), were used less frequently. Sensitivity analyses indicated that pooled estimates were generally robust, although results should be interpreted cautiously given methodological variability across studies. CONCLUSIONS: Medical specialists predominantly rely on standalone information sources when addressing clinical questions, while systematically aggregated and interpreted sources such as clinical practice guidelines and point-of-care tools are used less frequently. These findings highlight the need to better understand and address barriers to the use of aggregated information sources in clinical practice. PROSPERO REGISTRATION NUMBER: CRD42022267431.