Background: Nowadays most of the intensive care units (ICUs) operate as a closed format in comparison to an open format. The new concept of a closed ICU is where patients are admitted under the full responsibility of a trained intensivist, whereas an open ICU is where patients are admitted under the care of another attending physician and intensivists are just available for consultation. In this analysis, we aimed to systematically compare mortality rate and other clinical features observed in open vs closed ICU formats. Methods: Biomedical and pharmacological bibliographic database Excerpta Medica database (EMBASE), Medical Literature Analysis and Retrieval System Online (MEDLINE), the Cochrane Central and www.ClinicalTrials.gov were searched for required English publications. Mortality, the frequency of patients requiring mechanical ventilation, central line, arterial line and pulmonary arterial catheter were assessed respectively. Statistical analysis was carried out by the RevMan software. Odds ratios (OR) with 95% confidence intervals (CIs) were used to represent the data following analysis. Results: Five studies with a total number of 6160 participants enrolled between years 1992 to 2007 were included. Results of this analysis showed that mortality rate was significantly higher in the open format ICU (OR: 1.31, 95% CI: 1.17–1.48; P = .00001) (using a fixed effect model) and (OR: 1.31, 95% CI: 1.09–1.59; P = .005) (using a random effect model). Closed format ICUs were associated with significantly higher number of patients that required central line (OR: 0.56, 95% CI: 0.34–0.92; P = .02). Patients requiring mechanical ventilation (OR: 1.08, 95% CI: 0.65–1.78; P = .77), patients requiring arterial line (OR: 1.05, 95% CI: 0.49–2.29; P = .89) and patients requiring pulmonary arterial catheter (OR: 0.86, 95% CI: 0.40–1.87; P = .71) were similar in the open vs the closed setting. Conclusion: This analysis showed that mortality rate was significantly higher in an open as compared to a closed format ICU. However, the frequency of patients requiring mechanical ventilation, arterial line and pulmonary arterial catheter was similarly observed. Larger trials are expected to further confirm those hypotheses.