Extended Data Fig. 5: Forest plots of pooled rate ratios for number of cancer treatment deliveries before and during the COVID-19 pandemic.
Two-tailed Z-scores, following a natural logarithmic transformation were used to calculate p-values, with the DerSimonian and Laird method pooling effect estimates. The square box represents rate ratio (RR) and the size of the box represents study weight. Diamond represents pooled RR. Dotted vertical line represents overall effect. Horizontal bars indicate 95% CIs. Vertical solid black line represents no effect. a–c Analyses of 122 studies showed Asia had the highest reduction in overall cancer treatment (RR = 0.63; 95% CI: 0.57 to 0.70) (between 652,459 and 15,498,757 participants). The highest reductions were for musculoskeletal cancers (RR = 0.47; 95% CI: 0.36 to 0.61) (332,251 pre-COVID-19 and 285,261 during COVID-19), and for oral cavity cancers (RR = 0.13; 95% CI: 0.10 to 0.17) (319,916 pre-COVID-19 and 275,562 during COVID-19). d-f Analyses of 90 studies (616,101 participants) showed the highest decrease in surgical treatment in medium HDI countries (RR = 0.54; 95% CI: 0.47 to 0.63) and for head and neck cancers (RR = 0.45; 95% CI: 0.26 to 0.78). Africa had the highest reduction for head and neck cancers (RR = 0.21; 95% CI: 0.14 to 0.32). The highest reduction by cancer group was for musculoskeletal cancers (RR = 0.50; 95% CI: 0.38 to 0.66). g–i Analyses of 18 studies (33,994 participants) showed the greatest reduction in medium HDI countries and for head and neck cancers (RR = 0.13, 95% CI: 0.08 to 0.22). The largest reduction by site was for neurological cancers (RR = 0.78, 95% CI: 0.66 to 0.92). j-l Analyses of 25 studies (24,897 participants) showed the largest decrease for breast cancer in very high HDI (RR = 0.65; 95% CI: 0.49 to 0.87) and high HDI countries (RR = 0.38; 95% CI: 0.31 to 0.47), and for haematological cancers in medium HDI countries (RR = 0.16; 95% CI: 0.15 to 0.18). The highest decline was in Asia for musculoskeletal cancers (RR = 0.32; 95% CI: 0.16 to 0.64). m) The increase in time from diagnosis to treatment was not statistically significant (P = 0.13).
