Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective:To explore the relationship between relapse tendency and childhood maltreatment in methamphetamine-dependent youths,and the role of impulsivity and quality of life in the relationship.Methods:To-tally 287 methamphetamine-dependent youths(160 females,127 males)were selected in compulsory drug rehabili-tation centers.The Relapse Tendency Questionnaire(RTQ),Childhood Trauma Questionnaire-Short Form(CTQ-SF),Barrett Impulsivity Scale(BIS-11)and Quality of Life for Drug Addicts(QOL-DA)for Drug Addicts were used to conduct the survey.SPSS macro program PROCESS was used to test the mediating role.Results:The BIS-11 total scores acted as a partial mediator between the total scores of CTQ-SF and RTQ,with an effect value of 0.03(95％CI:0.01-0.05),the QOL-DA total scores acted as a full mediator between the total scores of CTQ-SF and RTQ,with an effect value of 0.05(95％CI:0.02-0.08),and the scores of BIS-11 and QOL-DA acted as chain mediators between total scores of CTQ-SF and RTQ,with an effect value of 0.01(95％CI:0.00-0.03).Conclusion:Childhood maltreatment,impulsivity,and quality of life may be associated with relapse tendencies in methamphetamine-dependent youths.

Objective:To analyze the risk factors for complications of the retromandibular approach in patients with parotid gland posterior and lower pole tumors.Methods:A retrospective analysis was conducted on the clinical data of 140 patients with parotid posterior lower pole tumors admitted to the Xingtai Third Hospital from October 2019 to October 2021. They were divided into two groups based on whether complications occurred: the occurrence group and the non occurrence group. General data of the two groups of patients were collected, including age, gender, course of disease, previous surgical history, number of tumors, tumor length, resection range, facial nerve dissociation, tumor site resection frequency, and fascia preservation; Single factor and logistic multivariate analysis were conducted to determine the risk factors for complications of the posterior retromandibular approach in patients with parotid gland posterior and lower pole tumors.Results:A total of 140 patients with parotid gland posterior lower pole tumors underwent retromandibular approach treatment, with complications occurring in 38 cases (27.14%), including 7 cases of temporary facial paralysis, 10 cases of facial depression, 11 cases of Frey syndrome, 2 cases of fistula, and 8 cases of sensory abnormalities of the greater auricular nerve. Through logistic multivariate analysis, it was found that the number of tumors ≥ 2 ( OR=2.856), the resection range (total resection) ( OR=2.477), the number of surgeries ≥3 ( OR=5.637), facial nerve dissociation ( OR=3.526), and lack of fascia preservation ( OR=2.551) were all risk factors for postoperative complications in patients with parotid posterior pole tumors (all P<0.05). Conclusions:In clinical practice, relevant prevention and treatment measures should be formulated for these high-risk factors to reduce the incidence of postoperative complications.

Objective:To construct a quantitatively diagnostic nomogram model by analyzing the clinical information of patients and the features of multi-modality ultrasound images of thyroid lesions, so as to preoperatively predict the malignant probability of suspicious thyroid nodules and provide effective references for clinical decision-making.Methods:A total of 933 patients, 1 121 thyroid nodules of C-TIRADS 3-5 categories, who underwent surgery in the Second Affiliated Hospital of Harbin Medical University from September 1, 2020 to June 10, 2021 were collected. The nodules were randomly divided into training ( n=897) and test groups ( n=224) in 8∶2 ratio. Finally, the diagnostic performance was evaluated by area under the curve (AUC). Results:①After preliminary screening by univariate analysis, multivariate analysis showed that age, echogenicity, orientation, echogenic foci, margin, posterior features, and elastic score were significantly correlated with benign and malignant nodules (all P<0.001), and the difference of halo between benign and malignant nodules was also statistically significant ( P=0.012). ②The AUC of nomogram was up to 0.903(95% CI=0.862-0.944) in the test set, and 0.889(95% CI=0.832-0.946) and 0.960(95% CI=0.925-0.994) in nodules with maximum diameter of ≤10 mm and of >10 mm respectively, which showed high diagnostic performance. Conclusions:The nomogram model could accurately differentiate malignant from benign thyroid nodules preoperatively, with the highest diagnostic performance for the nodules with maximum diameter of >10 mm, and effectively avoid the unnecessary fine-needle biopsy and surgical operation.

OBJECTIVE To study the quality grade stand ard of the premature Forsythia suspensa . METHODS A total of 138 batches of premature F. suspensa were collected from the main producing areas of F. suspensa in China. According to 2020 edition of Chinese Pharmacopoeia ，the contents of impurities ，moisture，ethanol-soluble extract ，volatile oil ，forsythin and forsythoside A in the premature F. suspense were determined ，and the qualified samples were screened. AHP-PCA mixed weighting method was used to give comprehensive weight to the indicators （except for the limit of impurity ）. The comprehensive score of the samples was calculated. The suggestions on the quality grade division of premature F. suspensa were put forward according to cluster analysis of K-mean value. RESULTS & CONCLUSIONS The contents of impurities ，moisture，ethanol-soluble extract ，volatile oil ，forsythin and forsythoside A in the premature F. suspense were 0-7.80％，1.60％-8.18％，13.13％-61.60％，0.21％-3.47％，0.02％-2.15％ and 0.79％-14.04％，respectively；average contents of them were 1.24％，4.97％，34.88％，2.01％，0.42％，6.86％，respectively. Totally 47 batches of 138 batches were qualified in all indexes. It is suggested that the quality grade of the premature F. suspense can be divided into three grades ：in first grade of F. suspense ，the contents of volatile oil ，forsythin，forsythoside A ， ethanol-soluble extract and moisture were ≥2.40％，≥0.59％，≥8.34％，≥38.66％ and ≤4.99％，respectively；in second grade of F. suspense ，the contents of above indicators were ≥2.26％，≥0.41％，≥7.47％，≥32.58％ and ≤5.33％，respectively；in third grade of F. suspense ，the contents of above indicators were ≥2.15％，≥0.32％，≥4.60％，≥31.52％ and≤7.23％，respectively.

Objective:To investigate the correlation between the door-to-needle time (DNT) delay and the short-term functional outcome after intravenous thrombolysis in patients with minor ischemic stroke and the influencing factors of DNT delay.Methods:From October 2016 to May 2018, patients with minor ischemic stroke received intravenous thrombolysis with alteplase from the Stroke Database of Nanjing First Hospital were enrolled retrospectively. DNT delay was defined as DNT > median. The modified Rankin Scale was used to evaluate the short-term functional outcome at 3 months after stroke. 0-1 was defined as good outcome, and ≥2 was defined as poor outcome. Univariate analysis was used to evaluate the correlation between DNT delay and short-term functional outcome. Multivariate logistic regression analysis was used to evaluate the possible influencing factors of DNT delay. Results:A total of 102 patients with minor ischemic stroke were enrolled. The median DNT was 40 min, 36 patients (35.3%) had DNT delay, and 27 patients (26.5%) had poor short-term outcome. Univariate analysis showed that there was no significant difference in the proportion of patients with DNT delay between the poor outcome group and the good outcome group (44.4% vs. 32.0%; χ2=1.346, P=0.252). Multivariate logistic regression analysis showed that there was a significant independent negative correlation between hypertension and DNT delay (odds ratio 0.359, 95% confidence interval 0.137-0.939; P=0.037). Conclusion:For patients with minor ischemic stroke receiving intravenous thrombolysis, DNT delay is not associated with the outcome. The absence of hypertension may be one of the factors affecting the DNT delay.

Objective:To evaluate the efficacy of three-dimensional (3D) visualization technology in the precision diagnosis and treatment for primary liver cancer.Methods:A total of 1 665 patients with primary liver cancer who admitted to seven medical centers in China between January 2009 to January 2019, diagnosed and treated by 3D visualization protocol were analyzed, and their clinical data were retrospectively reviewed. There were 1 255 males (75.4%) and 410 females (24.6%) , with age of (52.9±11.9) years (range: 18 to 86 years) .The acquisition of high-quality CT images with submillimeter spatial resolution were conducted using a quality control system. By means of homogenization methods, 3D reconstruction and 3D visualization analysis were performed. Postoperative observation: pathology reports, microvascular invasion, perioperative complications and follow-up. SPSS 25.0 statistical software was used for statistical description and analysis of clinical data.Results:In the sample of 1 265 patients, 3D reconstructed models clearly displayed in follows. (1) tumor size: ≤2 cm in 155 cases (9.31%) , >2 cm to 5 cm in 551 cases (33.09%) , >5 cm to 10 cm in 636 cases (38.20%) , >10 cm in 323 cases (19.40%) . (2) Classification of hepatic blood vessels. Hepatic artery: type Ⅰ (normal type) in 1 494 cases (89.73%) ,variant hepatic artery in 171 cases (10.27%) , including type Ⅱ in 35 cases, type Ⅲ in 38 cases, and other types in 98 cases. Hepatic vein: type Ⅰ (normal) in 1 195 cases (71.77%) ,variant hepatic veins in 470 cases (28.23%) , including type Ⅱ in 376 cases and type Ⅲ in 94 cases. Portal vein: normal type in 1 315 cases (78.98%) ,variant portal veins in 350 cases (21.02%) , including type Ⅰ in 189 cases, type Ⅱin 103 cases, type Ⅲ in 50 cases, type Ⅳ in 8 cases. Hepatic artery variation coexisting with portal vein variation in 24 cases (1.44%) . Hepatic vein variation coexisting with portal vein variation in 113 cases (6.79%) . Three types of vascular variation in 4 cases (0.24%) , including coexistence of type Ⅱ hepatic artery variation or type Ⅰ portal vein variation with type Ⅲ hepatic vein variation in 2 cases,coexistence of type Ⅲ hepatic artery variation or type Ⅲ portal vein variation with type Ⅱ hepatic vein variation in 2 cases. (3) Preoperative liver volume calculation: 1 499.3 (514.4) ml (range: 641.7 to 6 637.0 ml) of total liver volume, including 479.1 (460.1) ml (range:10.5 to 2 086.8 ml) for liver resection and 959.9 (460.4) ml (range:306.1 to 5 638.0 ml) for residual function. (4) Operative methods: anatomical hepatectomy in 1 458 cases (87.57%) ; non-anatomic hepatectomy in 207 cases (12.43%) . (5) the median operation time was 285 (165) minutes (range: 40 to720 minutes) . (6) The median intraoperative blood loss was 200 (250) ml (range:10 to 4 200 ml) and 346 cases (20.78%) had intraoperative transfusion. (7) Pathology reports: hepatocellular carcinoma in 1 371 cases (82.34%) , cholangiocarcinoma in 260 cases (15.62%) and mixed hepatocellular carcinoma in 34 cases (2.04%) . Microvascular invasion: M0 in 199 cases, M1 in 64 cases, and M2 in 27 cases. (8) Postoperative complications in 207 cases (12.43%) , including Clavien-Dindo grade Ⅰ or Ⅱ in 57 cases, grade Ⅲ or Ⅳ in 147 cases and grade Ⅴ in 3 cases.There were 13 cases (0.78%) of liver failure and 3 cases (0.18%) of perioperative death. (9) The follow-up time was 3.0 to 96.0 months, with a median time of 21.0(17.8) years. The overall 3-year survival and disease-free survival rates were 80.0% and 56.5%, respectively. The overall 5-year survival and disease-free survival rates were 59.7% and 30.0%, respectively.Conclusion:3D visualization technology plays an important role in realizing accurate diagnosis of anatomical location and morphology of primary liver cancer, improving the success rate of surgery and reducing the incidence of complications.

Objective:To evaluate the efficacy of three-dimensional(3D) visualization technology in the precision diagnosis and treatment for primary liver cancer.Methods:A total of 1 665 patients with primary liver cancer who admitted to seven medical centers in China between January 2009 to January 2019, diagnosed and treated by 3D visualization protocol were analyzed, and their clinical data were retrospectively reviewed. There were 1 255 males(75.4%) and 410 females(24.6%), with age of (52.9±11.9) years (range: 18 to 86 years). The acquisition of high-quality CT images with submillimeter spatial resolution were conducted using a quality control system. By means of homogenization methods, 3D reconstruction and 3D visualization analysis were performed. Postoperative observation: pathology reports, microvascular invasion, perioperative complications and follow-up. SPSS 25.0 statistical software was used for statistical description and analysis of clinical data. Kaplan-Meier curve was used to calculate overall survival and disease-free survival rate.Results:(1)In the sample of 1 265 patients, 3D reconstructed models clearly displayed as follows. tumor size: ≤2 cm in 155 cases (9.31%), >2 cm to 5 cm in 551 cases (33.09%), >5 cm to 10 cm in 636 cases (38.20%), >10 cm in 323 cases (19.40%). (2) Classification of hepatic blood vessels. Hepatic artery: type Ⅰ(normal type) in 1 494 cases(89.73%),variant hepatic artery in 171 cases (10.27%), including type Ⅱ in 35 cases, type Ⅲ in 38 cases, and other types in 98 cases. Hepatic vein: type Ⅰ (normal) in 1 195 cases (71.77%),variant hepatic veins in 470 cases(28.23%), including type Ⅱ in 376 cases and type Ⅲ in 94 cases. Portal vein:normal type in 1 315 cases (78.98%), variant portal veins in 350 cases (21.02%), including type Ⅰ in 189 cases, type Ⅱin 103 cases, type Ⅲ in 50 cases, type Ⅳ in 8 cases. Hepatic artery variation coexisting with portal vein variation in 24 cases (1.44%). Hepatic vein variation coexisting with portal vein variation in 113 cases (6.79%). Three types of vascular variation in 4 cases (0.24%), including coexistence of type Ⅱ hepatic artery variation or type Ⅰ portal vein variation with type Ⅲ hepatic vein variation in 2 cases,coexistence of type Ⅲ hepatic artery variation or type Ⅲ portal vein variation with type Ⅱ hepatic vein variation in 2 cases. (3) Preoperative liver volume calculation:1 499.3 (514.4)ml (range:641.7 to 6 637.0 ml) of total liver volume, including 479.1 (460.1) ml (range:10.5 to 2 086.8 ml) for liver resection and 959.9 (460.4)ml (range:306.1 to 5 638.0 ml) for residual function. (4)Operative methods: anatomical hepatectomy in 1 458 cases (87.57%); non-anatomic hepatectomy in 207 cases (12.43%). (5)the median operation time was 285(165)minutes (range: 40 to720 minutes). (6)The median intraoperative blood loss was 200(250)ml (range:10 to 4 200 ml) and 346 cases (20.78%) had intraoperative transfusion. (7)Pathology reports: hepatocellular carcinoma in 1 371 cases (82.34%), cholangiocarcinoma in 260 cases (15.62%) and mixed hepatocellular carcinoma in 34 cases (2.04%). Microvascular invasion: M0 in 199 cases, M1 in 64 cases, and M2 in 27 cases. (8)Postoperative complications in 207 cases (12.43%), including Clavien-Dindo grade Ⅰ or Ⅱ in 57 cases, grade Ⅲ or Ⅳ in 147 cases and grade Ⅴ in 3 cases.There were 13 cases (0.78%) of liver failure and 3 cases (0.18%) of perioperative death. (9) The follow-up time was 3.0 to 96.0 months, with a median time of 21.0(17.8) years. The overall 3-year survival and disease-free survival rates were 80.0% and 56.5%, respectively. The overall 5-year survival and disease-free survival rates were 59.7% and 30.0%, respectively.Conclusion:3D visualization technology plays an important role in realizing accurate diagnosis of anatomical location and morphology of primary liver cancer, improving the success rate of surgery and reducing the incidence of complications.

Objective:To evaluate the efficacy of three-dimensional (3D) visualization technology in the precision diagnosis and treatment for primary liver cancer.Methods:A total of 1 665 patients with primary liver cancer who admitted to seven medical centers in China between January 2009 to January 2019, diagnosed and treated by 3D visualization protocol were analyzed, and their clinical data were retrospectively reviewed. There were 1 255 males (75.4%) and 410 females (24.6%) , with age of (52.9±11.9) years (range: 18 to 86 years) .The acquisition of high-quality CT images with submillimeter spatial resolution were conducted using a quality control system. By means of homogenization methods, 3D reconstruction and 3D visualization analysis were performed. Postoperative observation: pathology reports, microvascular invasion, perioperative complications and follow-up. SPSS 25.0 statistical software was used for statistical description and analysis of clinical data.Results:In the sample of 1 265 patients, 3D reconstructed models clearly displayed in follows. (1) tumor size: ≤2 cm in 155 cases (9.31%) , >2 cm to 5 cm in 551 cases (33.09%) , >5 cm to 10 cm in 636 cases (38.20%) , >10 cm in 323 cases (19.40%) . (2) Classification of hepatic blood vessels. Hepatic artery: type Ⅰ (normal type) in 1 494 cases (89.73%) ,variant hepatic artery in 171 cases (10.27%) , including type Ⅱ in 35 cases, type Ⅲ in 38 cases, and other types in 98 cases. Hepatic vein: type Ⅰ (normal) in 1 195 cases (71.77%) ,variant hepatic veins in 470 cases (28.23%) , including type Ⅱ in 376 cases and type Ⅲ in 94 cases. Portal vein: normal type in 1 315 cases (78.98%) ,variant portal veins in 350 cases (21.02%) , including type Ⅰ in 189 cases, type Ⅱin 103 cases, type Ⅲ in 50 cases, type Ⅳ in 8 cases. Hepatic artery variation coexisting with portal vein variation in 24 cases (1.44%) . Hepatic vein variation coexisting with portal vein variation in 113 cases (6.79%) . Three types of vascular variation in 4 cases (0.24%) , including coexistence of type Ⅱ hepatic artery variation or type Ⅰ portal vein variation with type Ⅲ hepatic vein variation in 2 cases,coexistence of type Ⅲ hepatic artery variation or type Ⅲ portal vein variation with type Ⅱ hepatic vein variation in 2 cases. (3) Preoperative liver volume calculation: 1 499.3 (514.4) ml (range: 641.7 to 6 637.0 ml) of total liver volume, including 479.1 (460.1) ml (range:10.5 to 2 086.8 ml) for liver resection and 959.9 (460.4) ml (range:306.1 to 5 638.0 ml) for residual function. (4) Operative methods: anatomical hepatectomy in 1 458 cases (87.57%) ; non-anatomic hepatectomy in 207 cases (12.43%) . (5) the median operation time was 285 (165) minutes (range: 40 to720 minutes) . (6) The median intraoperative blood loss was 200 (250) ml (range:10 to 4 200 ml) and 346 cases (20.78%) had intraoperative transfusion. (7) Pathology reports: hepatocellular carcinoma in 1 371 cases (82.34%) , cholangiocarcinoma in 260 cases (15.62%) and mixed hepatocellular carcinoma in 34 cases (2.04%) . Microvascular invasion: M0 in 199 cases, M1 in 64 cases, and M2 in 27 cases. (8) Postoperative complications in 207 cases (12.43%) , including Clavien-Dindo grade Ⅰ or Ⅱ in 57 cases, grade Ⅲ or Ⅳ in 147 cases and grade Ⅴ in 3 cases.There were 13 cases (0.78%) of liver failure and 3 cases (0.18%) of perioperative death. (9) The follow-up time was 3.0 to 96.0 months, with a median time of 21.0(17.8) years. The overall 3-year survival and disease-free survival rates were 80.0% and 56.5%, respectively. The overall 5-year survival and disease-free survival rates were 59.7% and 30.0%, respectively.Conclusion:3D visualization technology plays an important role in realizing accurate diagnosis of anatomical location and morphology of primary liver cancer, improving the success rate of surgery and reducing the incidence of complications.

Objective:To evaluate the efficacy of three-dimensional(3D) visualization technology in the precision diagnosis and treatment for primary liver cancer.Methods:A total of 1 665 patients with primary liver cancer who admitted to seven medical centers in China between January 2009 to January 2019, diagnosed and treated by 3D visualization protocol were analyzed, and their clinical data were retrospectively reviewed. There were 1 255 males(75.4%) and 410 females(24.6%), with age of (52.9±11.9) years (range: 18 to 86 years). The acquisition of high-quality CT images with submillimeter spatial resolution were conducted using a quality control system. By means of homogenization methods, 3D reconstruction and 3D visualization analysis were performed. Postoperative observation: pathology reports, microvascular invasion, perioperative complications and follow-up. SPSS 25.0 statistical software was used for statistical description and analysis of clinical data. Kaplan-Meier curve was used to calculate overall survival and disease-free survival rate.Results:(1)In the sample of 1 265 patients, 3D reconstructed models clearly displayed as follows. tumor size: ≤2 cm in 155 cases (9.31%), >2 cm to 5 cm in 551 cases (33.09%), >5 cm to 10 cm in 636 cases (38.20%), >10 cm in 323 cases (19.40%). (2) Classification of hepatic blood vessels. Hepatic artery: type Ⅰ(normal type) in 1 494 cases(89.73%),variant hepatic artery in 171 cases (10.27%), including type Ⅱ in 35 cases, type Ⅲ in 38 cases, and other types in 98 cases. Hepatic vein: type Ⅰ (normal) in 1 195 cases (71.77%),variant hepatic veins in 470 cases(28.23%), including type Ⅱ in 376 cases and type Ⅲ in 94 cases. Portal vein:normal type in 1 315 cases (78.98%), variant portal veins in 350 cases (21.02%), including type Ⅰ in 189 cases, type Ⅱin 103 cases, type Ⅲ in 50 cases, type Ⅳ in 8 cases. Hepatic artery variation coexisting with portal vein variation in 24 cases (1.44%). Hepatic vein variation coexisting with portal vein variation in 113 cases (6.79%). Three types of vascular variation in 4 cases (0.24%), including coexistence of type Ⅱ hepatic artery variation or type Ⅰ portal vein variation with type Ⅲ hepatic vein variation in 2 cases,coexistence of type Ⅲ hepatic artery variation or type Ⅲ portal vein variation with type Ⅱ hepatic vein variation in 2 cases. (3) Preoperative liver volume calculation:1 499.3 (514.4)ml (range:641.7 to 6 637.0 ml) of total liver volume, including 479.1 (460.1) ml (range:10.5 to 2 086.8 ml) for liver resection and 959.9 (460.4)ml (range:306.1 to 5 638.0 ml) for residual function. (4)Operative methods: anatomical hepatectomy in 1 458 cases (87.57%); non-anatomic hepatectomy in 207 cases (12.43%). (5)the median operation time was 285(165)minutes (range: 40 to720 minutes). (6)The median intraoperative blood loss was 200(250)ml (range:10 to 4 200 ml) and 346 cases (20.78%) had intraoperative transfusion. (7)Pathology reports: hepatocellular carcinoma in 1 371 cases (82.34%), cholangiocarcinoma in 260 cases (15.62%) and mixed hepatocellular carcinoma in 34 cases (2.04%). Microvascular invasion: M0 in 199 cases, M1 in 64 cases, and M2 in 27 cases. (8)Postoperative complications in 207 cases (12.43%), including Clavien-Dindo grade Ⅰ or Ⅱ in 57 cases, grade Ⅲ or Ⅳ in 147 cases and grade Ⅴ in 3 cases.There were 13 cases (0.78%) of liver failure and 3 cases (0.18%) of perioperative death. (9) The follow-up time was 3.0 to 96.0 months, with a median time of 21.0(17.8) years. The overall 3-year survival and disease-free survival rates were 80.0% and 56.5%, respectively. The overall 5-year survival and disease-free survival rates were 59.7% and 30.0%, respectively.Conclusion:3D visualization technology plays an important role in realizing accurate diagnosis of anatomical location and morphology of primary liver cancer, improving the success rate of surgery and reducing the incidence of complications.