[Distribution of serum pepsinogen I, II values and their ratios in residents of a rural area].

In order to adopt pepsinogen levels as a screening indicator of gastric cancer, the serum pepsinogen I (PG I) and serum pepsinogen II (PG II) levels were studied using one thousand samples from a rural area and their ratios PG I/PG II were calculated. Samples were collected by stratified random sampling of the residents in S town with a population of about 10,000. The collected data was statistically analyzed to determine distributions by respective categories of sex and age. The following results were obtained. 1. The distributions of PG I, PG II and their ratio PG I/PG II levels largely deviated from normal distributions. Therefore, it is recommended that non-parametrical method is used to analyze this data. 2. The median of PG I level (49.3 micrograms/l) in males was statistically higher than that (43.6 micrograms/l) in females. On the other hand, a statistically significant difference between males and females was not observed in either the PG II value or the ratio PG I/PG II, respectively. 3. The pattern for changes in PG I values with age was different between males and females. While PG I levels were almost constant until the sixties, after the seventies levels showed a marked decrease in male subjects. In female subjects, an age effect in levels was not observed for PG I. On the other hand, PG II levels increased with age except for age group seventies, and the PG I/PG II ratios showed a decreasing tendency in both males and females.