This study investigated the performance of various case definitions and influenza symptoms in a primary healthcare sentinel surveillance system. A retrospective study of the clinical and epidemiological characteristics of the cases reported by a primary healthcare sentinel surveillance network for eleven years in Catalonia was conducted. Crude and adjusted diagnostic odds ratios (aDORs) and 95% confidence intervals (CIs) of the case definitions and symptoms for all weeks and epidemic weeks were estimated. The most predictive case definition for laboratory-confirmed influenza was the World Health Organization (WHO) case definition for ILI in all weeks (aDOR 2.69; 95% CI 2.42-2.99) and epidemic weeks (aDOR 2.20; 95% CI 1.90-2.54). The symptoms that were significant positive predictors for confirmed influenza were fever, cough, myalgia, headache, malaise, and sudden onset. Fever had the highest aDOR in all weeks (4.03; 95% CI 3.38-4.80) and epidemic weeks (2.78; 95% CI 2.21-3.50). All of the case definitions assessed performed better in patients with comorbidities than in those without. The performance of symptoms varied by age groups, with fever being of high value in older people, and cough being of high value in children. In patients with comorbidities, the performance of fever was the highest (aDOR 5.45; 95% CI 3.43-8.66). No differences in the performance of the case definition or symptoms in influenza cases according to virus type were found.

中文翻译：

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流感临床定义对公共卫生监测目的的有用性。

本研究调查了初级卫生保健哨点监测系统中各种病例定义和流感症状的表现。对加泰罗尼亚初级卫生保健哨点监测网络报告病例的临床和流行病学特征进行了 11 年的回顾性研究。估计了所有周和流行周的病例定义和症状的粗略和调整后诊断比值比 (aDOR) 和 95% 置信区间 (CI)。实验室确诊流感最具预测性的病例定义是世界卫生组织 (WHO) 对所有周 (aDOR 2.69; 95% CI 2.42-2.99) 和流行周 (aDOR 2.20; 95% CI 1.90-2.54) 的 ILI 病例定义. 作为确诊流感的显着阳性预测因子的症状是发烧、咳嗽、肌痛、头痛、身体不适，突然发作。在所有周 (4.03; 95% CI 3.38-4.80) 和流行周 (2.78; 95% CI 2.21-3.50) 中，发烧的 aDOR 最高。评估的所有病例定义在有合并症的患者中比在没有合并症的患者中表现更好。症状表现因年龄组而异，老年人中发热高，儿童咳嗽高。在合并症患者中，发热的表现最高（aDOR 5.45；95% CI 3.43-8.66）。没有发现根据病毒类型在流感病例中病例定义或症状的表现存在差异。症状表现因年龄组而异，老年人中发热高，儿童咳嗽高。在合并症患者中，发热的表现最高（aDOR 5.45；95% CI 3.43-8.66）。没有发现根据病毒类型在流感病例中病例定义或症状的表现存在差异。症状表现因年龄组而异，老年人中发热高，儿童咳嗽高。在合并症患者中，发热的表现最高（aDOR 5.45；95% CI 3.43-8.66）。没有发现根据病毒类型在流感病例中病例定义或症状的表现存在差异。