Figure 1.
Flow chart of study selection process.
Table 1.
List of studies used in meta-analysis, country of analysis, date of conducted studies, age at diagnosis, mean age patients, number of patients in the study, percentage of males in study, years of follow-up, mortality rates and measurement of risk of mortality.
Figure 2.
Random effects meta-analysis by median study date (< = 1970, 1971–1980, 1981–1990, >1990).
Horizontal bars and circles widths denote 95% CIs, and box sizes indicate relative weight in the analysis.
Table 2.
Meta-analysis results by different categories, showing the number observations used, the pooled estimate and 95% confidence intervals and I2 estimate for heterogeneity.
Table 3.
Meta-regression results, determining the factors that account for the heterogeneity between different studies’ relative risk of mortality estimates.