Fig. 5

Forest plot of sub-group analysis pooled effect size (OR) estimates of anemia for tuberculosis infection by study design. The scale in the x-axis represents OR risk estimate of the studies. The hard line represents the odd ratio value showing no association (odds ratio of 1). The dashed line represents the pooled point estimate of OR of anemia for the tuberculosis infection. The black dot at the center of the gray box represents the point OR estimate of each study, and the line indicates the 95% confidence interval of the estimates. The gray boxes represent the weight of each study contributing to the pooled OR estimate. The first two blue diamonds represent the 95% confidence interval for sub group analysis pooled OR estimate and the last blue diamond represents the 95% confidence interval for overall pooled OR estimate. OR odds ratio, CI confidence interval, I² shows the heterogeneity of the included studies, p indicates the statistical significance of the heterogeneity, + anemia severity not defined, * mild anemia, & moderate and severe anemia, # moderate anemia, $ severe anemia