Independent Consultant, Seoul, Republic of Korea.
Global Health and Population Department, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America.
PLoS Med. 2019 Jun 14;16(6):e1002830. doi: 10.1371/journal.pmed.1002830. eCollection 2019 Jun.
Although there is mounting evidence demonstrating beneficial effects of community health workers (CHWs), few studies have examined the impact of CHW programs focused on preventing infectious diseases in children through behavior changes. We assessed the preventive effects of community health volunteers (CHVs), who receive no financial incentive, on child diarrhea and fever prevalence in Ghana.
We conducted a cluster-randomized controlled trial in 40 communities in the Volta Region, Ghana. Twenty communities were randomly allocated to the intervention arm, and 20 to the control arm, using a computer-generated block randomization list. In the intervention arm, CHVs were deployed in their own community with the key task of conducting home visits for health education and community mobilization. The primary outcomes of the trial were diarrhea and fever prevalence at 6 and 12 months among under-5 children based on caregivers' recall. Secondary outcomes included oral rehydration treatment and rapid diagnostic testing for malaria among under-5 children, and family planning practices of caregivers. Generalized estimating equations (GEEs) with a log link and exchangeable correlation matrix were used to determine the relative risk (RR) and 95% confidence intervals (CIs) for diarrhea, fever, and secondary outcomes adjusted for clustering and stratification. Between April 18 and May 4, 2015, 1,956 children were recruited and followed up until September 20, 2016. At 6 and 12 months post-randomization, 1,660 (85%) and 1,609 (82%) participants, respectively, had outcomes assessed. CHVs' home visits had no statistically significant effect on diarrhea or fever prevalence at either time point. After a follow-up of 12 months, the prevalence of diarrhea and fever was 7.0% (55/784) and 18.4% (144/784), respectively, in the control communities and 4.5% (37/825) and 14.7% (121/825), respectively, in the intervention communities (12-month RR adjusted for clustering and stratification: diarrhea, RR 0.73, 95% CI 0.37-1.45, p = 0.37; fever, RR 0.76, 95% CI 0.51-1.14, p = 0.20). However, the following were observed: improved hand hygiene practices, increased utilization of insecticide-treated bed nets, and greater participation in community outreach programs (p-values < 0.05) in the intervention group. In a post hoc subgroup analysis, the prevalence of diarrhea and fever at 6 months was 3.2% (2/62) and 17.7% (11/62), respectively, in the intervention communities with ≥70% coverage and a ≥30-minute visit duration, and 14.4% (116/806) and 30.2% (243/806) in the control communities (RR adjusted for clustering, stratification, baseline prevalence, and covariates: diarrhea, RR 0.23, 95% CI 0.09-0.60, p = 0.003; fever, RR 0.69, 95% CI 0.52-0.92, p = 0.01). The main limitations were the following: We were unable to investigate the longer-term effects of CHVs; the trial may have been underpowered to detect small to moderate effects due to the large decline in diarrheal and fever prevalence in both the intervention and control group; and caregivers' practices were based on self-report, and the possibility of caregivers providing socially desirable responses cannot be excluded.
We found no effect of CHVs' home visits on the prevalence of child diarrhea or fever. However, CHV programs with high community coverage and regular household contacts of effective duration may reduce childhood infectious disease prevalence.
International Standard Randomised Controlled Trial Registry, ISRCTN49236178.
尽管越来越多的证据表明社区卫生工作者（CHWs）具有有益效果，但很少有研究调查专注于通过行为改变预防儿童传染病的 CHW 计划的影响。我们评估了社区卫生志愿者（CHVs）的预防效果，他们没有获得任何经济激励，在加纳预防儿童腹泻和发热的流行。
我们在加纳沃尔特地区的 40 个社区进行了一项集群随机对照试验。使用计算机生成的块随机分组列表，将 20 个社区随机分配到干预组，20 个社区分配到对照组。在干预组中，CHVs 在自己的社区中部署，主要任务是进行家访进行健康教育和社区动员。试验的主要结局是根据护理人员的回忆，6 个月和 12 个月时 5 岁以下儿童腹泻和发热的流行率。次要结局包括 5 岁以下儿童口服补液治疗和快速诊断检测疟疾，以及护理人员计划生育实践。使用具有对数链接和可交换相关矩阵的广义估计方程（GEEs），确定腹泻、发热和调整聚类和分层的二级结局的相对风险（RR）和 95％置信区间（CI）。2015 年 4 月 18 日至 5 月 4 日，共招募了 1956 名儿童，并随访至 2016 年 9 月 20 日。随机分组后 6 个月和 12 个月，分别有 1660（85％）和 1609（82％）名参与者进行了评估。CHVs 的家访对腹泻或发热流行率在任何时间点均无统计学意义。在 12 个月的随访后，对照组腹泻和发热的流行率分别为 7.0％（55/784）和 18.4％（144/784），干预组分别为 4.5％（37/825）和 14.7％（121/825）（12 个月调整聚类和分层的 RR：腹泻，RR 0.73，95％CI 0.37-1.45，p = 0.37; 发热，RR 0.76，95％CI 0.51-1.14，p = 0.20）。但是，观察到以下情况：干预组的手部卫生习惯有所改善，使用杀虫剂处理过的蚊帐的比例增加，社区外展计划的参与度更高（p 值<0.05）。在事后亚组分析中，干预组 6 个月时腹泻和发热的流行率分别为 3.2％（62 名中的 2 名）和 17.7％（62 名中的 11 名），覆盖率≥70％，访视时间≥30 分钟，对照组分别为 14.4％（806 名中的 116 名）和 30.2％（806 名中的 243 名）（调整聚类、分层、基线流行率和协变量的 RR：腹泻，RR 0.23，95％CI 0.09-0.60，p = 0.003; 发热，RR 0.69，95％CI 0.52-0.92，p = 0.01）。主要限制包括以下内容：我们无法调查 CHVs 的家访对儿童腹泻或发热的长期影响;由于干预组和对照组的腹泻和发热流行率均大幅下降，试验可能因功率不足而无法检测到较小或中等程度的效果;而且，护理人员的做法是基于自我报告的，不能排除护理人员提供社会期望的反应的可能性。
我们没有发现 CHVs 家访对儿童腹泻或发热流行率的影响。但是，社区覆盖率高且定期进行有效家访的 CHV 计划可能会降低儿童传染病的流行率。
国际标准随机对照试验注册处，ISRCTN49236178。
