About this Article: This article describes a systematic literature review undertaken to examine the effectiveness of various population based health interventions. A discussion of interventions that have shown success, along with those that have shown no impact is presented along with recommendations for further research. Interventions involving pre- and post- natal visits, work with various homeless populations, prevention counseling with sex workers and violence prevention programs in schools show promise.
About This Series: The É/Exchange working paper series is designed to facilitate sharing of results and to encourage discussion of concepts, practices, and policies in applied health. This series provides a way to disseminate well-written, but not yet published, reports of research. It is also a way to make research conducted by affiliated community members accessible to a wider readership. The series is co-sponsored by The Population Health Improvement Research Network (PHIRN), Réseau de recherche appliquée sur la santé des francophones de l'Ontario (RRASFO); and the Ontario Health Human Resources Research Network (OHHRRN).
As the incidence of chronic disease and pressure to allocate public funds effectively rise, so have political and societal pressures to ensure that efforts to improve population and public health are directed to proven programs and services. Social determinants, such as social class, income, education and literacy, race and ethnicity, housing quality, and social relationships, can have an influence on health. A recent systematic review by Dobbins and Tirilis sought to identify and summarize research findings on the effectiveness of population based interventions on these social determinants.
The review was limited to studies of strong methodological quality and the search for topic related literature identified 31 such reviews, 17 of which were relevant to this synthesis. Most frequently reported outcomes in the literature included: health care utilization, mental health, physical health, and behavioural problems. Studied participants came from a wide range of populations.
The review identified interventions that were found to improve health outcomes among their target populations as follows:
- Home visits made by nurses to expectant mothers were associated with increased awareness of available community services, greater attendance at childbirth education classes, and speaking more frequently with service providers.
- Social support interventions for at-risk pregnant women resulted in fewer hospital admissions during pregnancy.
- Post-natal home visits to low socioeconomic status teenage mothers resulted in greater infant weight and height gains, and development scores.
- A telephone support and home visit program for very low-weight infants resulted in fewer re-hospitalizations and acute care visits, and lower incidence of failure to thrive, child abuse, and foster care placement.
- Pre- and post-natal home visits to high risk mothers with low socioeconomic status were associated with reductions in bladder infections and number of cigarettes smoked daily, as well as with improved nutrition, and better infant mental health. Counselling for this group also resulted in better recovery from postnatal depression.
- Assertive community treatment reduced homelessness and hospitalization outcomes among homeless people and in reduced homelessness and improved psychiatric symptom severity among homeless persons with severe mental illness.
- Strategies to prevent HIV and other sexually transmitted infections among female sex workers in resource-poor settings increased the use of preventive services and decreased infection rates.
- Intensive case management with access to drop-in centre services, temporary housing, and rehabilitation services for homeless persons with severe mental illness improved psychiatric symptoms and perceived quality of life. The number of contacts with treatment programming for members of this population resulted in improved psychiatric symptoms and decreased substance use.
- Housing support for those with intellectual disabilities and co-existing physical, mental or behavioural problems, and for homeless populations with concurrent mental illness and substance use disorders was associated with less hospitalization time and a greater number of days housed.
- A school-based program to prevent violent and aggressive behaviour resulted in a school-wide reduction in such behaviour. Intervention components included the provision of educational materials; cognitive therapy; social skills training; environmental changes; peer mediation and behaviour modification. Specific topics covered included: general violence; disruptive or anti-social behaviour; bullying; gang activity; and dating violence.
While the results illustrate that many population health and public health programs are associated with benefits to various populations, there remains cause for concern given some of the evidence suggests that various interventions may in fact widen health disparities.
What does not work?
While the following types of interventions may be effective as an integral part of a broader strategy, little or no impact was noted for the following types of interventions when undertaken alone:
- Health interventions among those with low literacy had no impact on long term health-related outcomes.
- Assertive community treatment for those with intellectual disability and co-existing physical, mental or behavioural problems, and for homeless populations with co-existing mental illness and substance use disorders, did not improve psychological and psychiatric function or reduce substance use.
- Case management approaches for those with substance use disorder, was no better than standard care on reported psychiatric symptoms.
- Health care services for populations with intellectual disabilities were not effective in improving behaviours.
- The provision of financial resources to families with low socio-economic status did not lead to significant improvements in behaviour among children and adolescents, and generally did not decrease rates of child maltreatment, physical/emotional/sexual abuse, visits to the emergency department, or injuries reported in the previous year.
Population based interventions on the social determinants of health has been identified as a priority topic area for Ontario. This systematic review has identified some promising interventions for practitioners to consider.
Reference: Dobbins, M., Tirilis, D. Social Determinants of Health: A Synthesis of Review Evidence. Exchange Working Paper Series, PHIRN S1 Issue 2. University of Ottawa, Ottawa, Canada. Available at rrasp-phirn.ca.