Objective Screening the Database from Colorectal Cancer (DACCA) based on West China Hospial data by " Operation Date”, we purposed to analyze the population characteristics of colorectal cancer patients in regional medical center within recent Database Version.Methods The DACCA Version was updated in December 12^th, 2018. Personal data (including sex, age, blood type, height, weight, and BMI), location data (including provinces, cities, and subordinate areas in Chengdu), occupation and education data, and main diagnosis data were included in the items. Characteristic analysis was performed on each selected data item.Results According to screening, 9 633 analytical data rows were obtained. Based on the database information, there were 24 consecutive years from 1995 to 2018 into every year. We set 2005 to 2006 as the time node for the database construction. The contribution to database before 2005 (including) was 1 358, while after 2005 (not including) were 8 275. The contribution rate (contribution numbers/years) after 2005 was higher than before 2005 ［1 358/11 vs. 8 275/13, 95% CI was (–625.337, –400.831), P<0.001］. According to gender distribution, total male data were 4 669, female were 3 340, non-checked were 1 624. According to age distribution, age were from 13 to 104 ［(59±13) years］. Linear prediction was used to predict the age distribution with the " year” as the time axis. The results showed the stable linear prediction (=0.016 1x+26.54, R²=3.42×10⁵, P=0.601 108). According to height, height were from 138 cm to 192 cm ［(161±7)cm］, linear prediction results showed that the linear variation with height changes by value (=0.110 5 x–60.911, R²=0.002 6, P=0.000 272). According to weight, weight were from 27.5 kg to 80.5 kg ［(59.38±10.27) kg］, linear prediction results showed that the linear variation with height changes by value (=0.296 5x–537.24, R²=0.010 625, P=2.37×10¹⁴). Available 6 884 data showed the difference between serving areas by West China Hospital and official definition of western region. A total of 9 209 data obtained by analyzing main diagnosis, showed that the main site of disease was rectum (68.64%). Sigmoid was the main location of colon cancer (68.64%), and anal-rectal cancer was main of rectal cancer (27.06%).Conclusion Population characteristics from DACCA database could initially reflect the trend of increasing weight and BMI of colorectal cancer patients, and also reflect the regional distribution characteristics based on geographic information. They would be the clues for further database research.

Citation： WANG Xiaodong, LI Xi, HE Xinlin, LI Li. Database research part Ⅰ: colorectal cancer from reginal medical center and population characteristics. CHINESE JOURNAL OF BASES AND CLINICS IN GENERAL SURGERY, 2019, 26(2): 212-220. doi: 10.7507/1007-9424.201901052 Copy