A Systematic Review and Meta-analysis on the Occurrence of Biomarker Mutation in Colorectal Cancer among the Asian Population

Table 3

Subgroup analysis. Prevalence of KRAS of patients with colorectal cancer stratified by study location of study.

	No. of Studies	Prevalence (%)	95% CI	(%)		Heterogeneity test
						DF
Location
Iraq	1	48.0	0.346-0.617	NA	NA	NA	NA
Iran	12	32.2	0.293-0.353	45.35	20.129	11	0.044
Jordan	2	46.9	0.412-0.527	0	0.514	1	0.474
Saudi Arabia	9	35.7	0.265-0.460	91.95	99.408	8	0.001
Japan	8	40.1	0.355-0.448	77.04	30.494	7	0.001
India	3	34.0	0.237-0.461	83.77	12.320	2	0.002
Taiwan	3	33.4	0.284-0.387	0	0.672	2	0.715
China	7	39.9	0.361-0.439	91.21	68.226	6	0.001
Thailand	1	47.2	0.380-0.566	NA	NA	NA	NA
South Korea	3	34.3	0.246–0.456	87.18	15.600	2	0.001
Kazakhstan	1	44.9	0.396-0.503	NA	NA	NA	NA
Oman	1	23.5	0.176-0.306	NA	NA	NA	NA
Singapore	2	34.4	0.299-0.392	0	0.145	1	0.703
Pakistan	1	13.3	0.088-0.198	NA	NA	NA	NA
Vietnam	1	37.1	0.298-0.451	NA	NA	NA	NA
Indonesia	1	71.8	0.559-0.836	NA	NA	NA	NA
Sri Lanka	1	23.1	0.161-0.320	NA	NA	NA	NA
Israel	1	44.9	0.402-0.497	NA	NA	NA	NA
Malaysia	1	25.0	0.144-0.397	NA	NA	NA	NA
Overall	59	36.3	0.345-0.382	85.54	401.015	58	0.001
KRAS subgroup by period of study conduct
2010 and below	19	32.3	0.288-0.360	90.78	187.902	18	0.001
After 2010	28	39.9	0.373-0.425	82.25	152.081	27	0.001
Early tumour stage^1	27	30.3	0.224-0.395	96.11	768.164	26	0.001
Late tumour stage^2	27	67.9	0.593-0.755	82.25	668.459	26	0.001
KRAS subgroup by tumour location
Colon	26	61.2	0.551-0.670	92.78	346.249	25	0.001
Rectum	26	39.3	0.336-0.453	92.34	326.498	25	0.001
KRAS subgroup by tumour grading
Poor	23	9.6	0.063-0.145	90.420	229.651	22	0.001
Moderate	23	52.1	0.429-0.612	94.777	421.176	22	0.001
Well	23	31.0	0.214-0.425	96.266	589.219	22	0.001

¹Implies stages 1 and 2; ²implies stages 3 and 4.