Are lay health workers effective in delivering health services for maternal and child health and in the management of infectious diseases?
Growing concern about the shortage of health care professionals, especially in low- and middle-income countries, has increased interest in the roles that lay health workers (LHWs) can play in delivering health services, particularly to hard-to-reach groups. LHWs are community members who have no formal education in health care, but have received training to promote and deliver certain interventions. A wide range of names for this cadre has been used in different settings, including community health workers, village health workers and health aides. Few studies, however, have focused on synthesizing the available research evidence on the effectiveness of LHWs.
This systematic review aimed to assess the effects of LHW interventions in primary and community health care on maternal and child health and the management of infectious diseases. Child health was defined as any intervention aimed at improving the health of children younger than 5 years old. Maternal health described any intervention aimed at improving reproductive health or ensuring safe motherhood or that targeted women in their role as caregivers for children under 5. Infectious diseases were included owing to their significant influence on maternal and child health. In this review, LHWs delivered interventions mainly through home visits. Other methods of delivery included telephone calls, postcards and interventions at primary care or community centres.
A total of 82 randomized controlled trials met the inclusion criteria. The effectiveness of LHWs was determined by grouping studies together according to the type of health issue addressed:
- increasing immunization uptake;
- reducing child morbidity and mortality;
- promoting breastfeeding;
- providing support for mothers of sick children;
- preventing/reducing child abuse;
- encouraging parent–child interaction and health promotion;
- supporting women with a high risk of low-birth-weight babies or poor pregnancy outcomes; and
- improving tuberculosis (TB) treatment and prophylaxis outcomes.
Owing to the diversity of the studies included, meta-analyses of outcomes could be conducted on only four of the eight groups (1–3, 8). Further, the number of studies in each analysis group was small: 5–18.
Moderate-quality evidence suggests that, when compared to usual health care services, LHWs are effective in increasing the proportion of children with up-to-date immunizations, promoting breastfeeding and improving cure rates for pulmonary TB. Nevertheless, moderate-quality evidence also suggests that LHW-led directly observed therapy was found to have little or no impact on the completion of preventive TB treatment, when compared to usual care. In addition, low-quality evidence suggested that LHW interventions may reduce child and neonatal mortality, increase the likelihood of parents’ seeking care for childhood illness and decrease child morbidity. At present, the evidence is insufficient to determine the effectiveness of LHW interventions on the remaining four groups of health issues.
The review findings indicate that LHW interventions to promote childhood immunization and breastfeeding, support treatment of pulmonary TB and reduce child morbidity and mortality are effective when compared to usual care. Policy-makers should consider incorporating LHWs into health service strategies for these four health issues. Additional research needs to be conducted before the effectiveness of LHWs in the remaining four groups can be determined.
As LHWs participate in some form of intervention-related training, incorporating them into health service strategies will require the development and delivery of training programmes. In addition, for some interventions, such as breastfeeding promotion, most studies required LHWs to have previous experience of the health issue. This is an important consideration for the selection of LHWs.
Caution should be used when generalizing these review results to low- and middle-income country settings, as many of the randomized controlled trials included were conducted in high-income countries. Nevertheless, most of the studies in these settings focused on low-income groups. Further, many of the included studies provided limited information on the education, selection and training of LHWs. The most effective training and intervention strategies therefore cannot be determined. In addition, data are lacking on the cost–effectiveness of LHW interventions, and this review did not examine the sustainability of the interventions.
Type of evidence
This study is an update of the 2005 systematic review focusing on the effects of LHW interventions in primary and community health care. The update reviewed 82 randomized controlled trials, 55 of which were conducted in high-income countries, while the remaining 27 were conducted in low- and middle-income countries. Most of the studies targeted people with low socioeconomic status. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to assess the quality of evidence on the effects of LHWs on health outcomes. Certain meta-analysis findings, particularly those related to breastfeeding, need to be interpreted with caution owing to unexplained statistical heterogeneity.