Objective To assess whether Community Periodontal Index (CPI) teeth and random half-mouth methods are representative of full-mouth method in gingival bleeding examination. Methods Data from 1000 untreated adults (age > 18) collected in Beijing from January 2000 to January 2001 were utilized in the analysis. Half of the subjects were examined by Gingival Bleeding Index (GBI) and the other half by Sulcus Bleeding Index (SBI). The data were sorted out and calculated according to CPI teeth and random half-mouth teeth methods. The results of the 2 methods were separately compared with those of full-mouth examination. Results There was a significant difference between CPI teeth method and full-mouth examination (P<0.05) in both GBI and SBI. In contrast, compared with full-mouth examination, significant difference was not observed in diagonal or ipsilateral half-mouth results in SBI (P>0.05), nor in diagonal half-mouth results in GBI (P>0.05) Conclusions The results of CPI teeth method on gingival bleeding could not reflect the full-mouth situation. Ipsilateral and diagonal half-mouth results can serve as a substitute for full-mouth results in SBI, while diagonal half-mouth results in GBI. Objective To assess whether Community Periodontal Index (CPI) teeth and random half-mouth methods are representative of full-mouth method in gingival bleeding examination. Methods Data from 1000 untreated adults (age> 18) collected in Beijing from January 2000 to January 2001 were utilized in the analysis. Half of the subjects were examined by the Gingival Bleeding Index (GBI) and the other half by Sulcus Bleeding Index (SBI). The data were sorted out and calculated according to CPI teeth and random half-mouth teeth methods. results of the 2 methods were separately compared with those of full-mouth examination. Results There was a significant difference between CPI teeth method and full-mouth examination (P <0.05) in both GBI and SBI. In contrast, compared with full-mouth examination examination, significant difference was not observed in diagonal or ipsilateral half-mouth results in SBI (P> 0.05), nor in diagonal half-mouth results in GBI (P> 0.05) Conclusions The results of CPI teeth method on gin gival bleeding could not reflect the full-mouth situation. Ipsilateral and diagonal half-mouth results in serve as a substitute for full-mouth results in SBI, while diagonal half-mouth results in GBI.