Table 1.

Numbers of patients in the study population and subgroups for the DNA ploidy analysis and dysplasia grading analysis

Total patients meeting inclusion criteria2,310
Excluded for lack of follow up data720 (31.2%)
Excluded for dysplasia or other diagnosis before 1990146 (6.3%)
Exclusions for minor reasons (see text)43 (1.9%)
Remaining patients divided into 2 study populations on basis of sufficient material for DNA ploidy analysisTotal patients in DNA ploidy analysisTotal patients in dysplasia analysis but not in DNA ploidy analysisOverall total patients in analysis
2731,1281,401
Number developing squamous carcinoma321749
Number of patients whose carcinoma developed within 6 months of index biopsy17522
Total number of patients remaining after exclusion of early transformation2561,1231,379
Number of patients whose carcinoma developed more than 6 months after index biopsy151227