A Systematic Review of Strategies for Reducing Missed Opportunities for Vaccination

This systematic review assessed the effects of interventions for reducing missed opportunities for vaccination (MOVs), which occur when persons eligible for vaccination visit a health facility and do not get the vaccines they need. Such missed opportunities make a substantial contribution to the 19.5 million children who fail to receive the basic set of routine vaccines scheduled for their first year of life.

Eligible interventions were those that led healthcare providers to check immunisation histories of people attending curative or preventive services in order to identify people eligible for vaccination and give them the required vaccine doses. Such interventions could be geared toward recipients of care (e.g., educating patients to prompt providers to check their vaccination cards), providers of care (e.g., training, supervision, reminders, audit and feedback, incentives), or the healthcare system (e.g. changing practices at healthcare clinics, systematic screening of immunisation histories of individuals admitted to hospital, bringing vaccination services closer to consultation rooms). Six studies (five trials and one cohort study) met the inclusion criteria, all conducted in the United States (US). The studies reported outcome data on MOVs and vaccination coverage for diphtheria-tetanus-pertussis (DTP), hepatitis B, influenza, Haemophilus influenzae type b (Hib), oral poliovirus (OPV), measles-mumps-rubella (MMR), and human papillomavirus (HPV) vaccines or completion of childhood immunisation schedule. All six studies had various limitations and were classified as having a high risk of bias.

The included studies evaluated the impact of several interventions versus a standard of care or no intervention on the rates of MOVs and uptake of vaccines.

1. One individually randomised trial assessed the effects of provider prompts with or without tracking by community health workers. A nurse screened the immunization histories of children visiting primary care facilities, irrespective of the purpose of the visit, and placed an MOV sticker on the charts of children in need of vaccination; specifying the required vaccine doses. Another study arm combined the provider prompts with tracking by community health workers. The latter identified under-vaccinated children through medical charts and used postcards, telephone calls, or home visits to recall them to their primary care providers to receive the needed vaccines.
2. The second individually randomised trial assessed the effects of a policy enforcing the screening and vaccination of all eligible children during all visits to primary care providers, with removal of legal guardian signature requirements. Staff nurses screened medical charts for vaccination status at all primary care visits and, if a vaccination was due, attached a brightly coloured vaccination reminder card to the front of the medical chart. Regarding the elimination of legal guardian's signature requirement, the legal guardian signed one consent form before the receipt of any vaccinations, and succeeding vaccinations were given without the need for additional consent.
3. The third individually randomised trial used case management and parent education. The case managers doing home visits or following up with participants by telephone and mail when immunisation was due. The case managers also had to educate or inform parents that it was safe to vaccinate the child whether they had a cold, mild ear infection, or any other mild diseases.
4. In the cohort study, a screening nurse produced computer printouts of vaccination records of each child at each acute care visit and attached the records to child's encounter form. In addition, during study visits, providers were given chocolate bars labeled, "Immunize On Time".
5. One of the cluster-randomised trials assessed the effects of a multi-faceted intervention consisting of: convenient vaccination services; communication with parents about the importance of immunisation and availability of vaccines; enhanced office systems to facilitate vaccination; and motivation through an office vaccination champion.
6. Another study assessed the effects of combining clinician-oriented and family-oriented interventions. The clinician-focused intervention consisted of electronic health record (EHR)-based vaccine awareness for any due vaccines, a one-hour educational presentation about the vaccine, and three quarterly performance feedback reports of captured immunisation opportunities at primary care visits. With regard to the family setting, the interventions involved automated phone calls to remind participants of any due vaccines and referrals to an educational website and reminders about upcoming preventive visits.

The researchers found moderate certainty evidence that the following interventions probably improve vaccination coverage: patient education (risk ratios (RR) 1.92, 95% confidence intervals (CI) 1.38-2.68), patient tracking using community health workers (RR 1.18, 95% CI 1.11-1.25), and patient tracking and provider prompts (RR 1.24, 95% CI 1.18-1.31). In addition, they found low certainty evidence that concurrent interventions targeting health-facility (education, prompts, and audit and feedback) and family settings (phone calls) may increase vaccination coverage (RR 1.25, 95% CI 1.08-1.46).

"Rigorous studies are required to confirm these findings and increase the certainty of the current evidence base."