TABLE 2

Characteristics of Included Studies

AuthorCountryPopulationNInterventionaComparatorOutcome(s)Study DesignResults
Effectiveness component
Yokley and Glenwick (1984)USAPreschoolers (aged <5) registered at public health clinic not UTD with vaccinations (as defined by local health department).Intervention, n = 183 children; control, n = 191 childrenParents sent tickets for cash lottery with prizes from $55.20 to $221 to be entered when attended clinic. Valid for 2 wk.Usual careN attending clinic for any reason, N attending for vaccination, N vaccinations given.Cluster RCT clustered at family level with follow-up at 2 wk, 2 mo, and 3 mo.At each follow-up time point intervention associated with significantly more attendance for any reason, attendance for vaccination, and number of vaccinations.
Mean (SD) age of children = 37.3 (18.2) months; 50% male.
Minkovitz et al (1999)USAWelfare claimants from Maryland. Children aged 3–24 mo; 51% male.Intervention children, n = 911; control, n = 864Penalty of loss of $38.70 from welfare benefits for failing to verify children’s preventive health care, including vaccinations.Usual careUTD for DTP, polio, and MMR (as per American Academy of Pediatrics).RCT with follow-up at 1 and 2 y.No difference in UTD rates for any vaccinations at 1 or 2 y follow-up.
Kerpelman et al (2000)USAWelfare claimants from Georgia. Mean age of intervention children = 3.22 y, 50% male. Mean age of control children = 3.34 y, 48.5% male.Intervention children, n = 1725; control children, n = 1076Penalty of loss of welfare benefit with amount depending on family size and child age.Usual careUTD for DTP, MMR, polio, Hib, HBV (as per American Academy of Pediatrics).RCT with follow-up at 1, 2, 3, and 4 y.At baseline no differences in uptake between intervention and control for any vaccination.
UTD for full series at age 2 y.At 1, 2, 3, and 4 y, intervention associated with greater uptake of all vaccinations. This difference was significant except for HBV at 1 y and Hib at 1 and 2 y.
At age 2, intervention associated with higher series completion.
Abrevaya and Mulligan (2011)USAState- and individual-level data on parents from National Immunization Surveys, 1996–2007.324 553 childrenDay care or school entry restricted to those with varicella vaccination.Usual careVaricella vaccination.Time series analysis from 1 y before intervention to 7 y after intervention.At state level, mandate has effect from year of introduction to 6 y after introduction. Effect peaking at 2 y after introduction.
Children aged 19–35 mo, 51% male.At individual level (controlling for child gender, race, age, maternal age, education, and income) mandate has effect from introduction to 5 y after introduction. Effect peaking at 2 y after introduction.
Acceptability component
Schaefer 1997USARecipients and staff of incentive program.1331Penalty of loss of $38.70 from welfare benefits for failing to verify children’s preventive health care including vaccinations.Usual careViews on interventions.Survey.73% of recipients thought penalty for noncompliance with health requirements was fair.
66.7% of recipients thought penalty would motivate parents to meet health requirements.
73.5% of staff thought behavior could be changed by threat of penalties. 77.8% by imposing penalties.
Most staff believed both the threat and imposition of penalty effective.
Freed et al (1998)USADistrict and county health department directors.75State laws allowing school or day care entry to be restricted, criminal misdemeanor charges to be brought, or injunctions to be filed against parents for not keeping children’s vaccinations UTD.No comparatorExperience of and views on intervention.Survey.100% aware of authority to enforce school and day care restrictions, 83% of criminal misdemeanor charges, 65% of injunctions.
99% believed nonvaccinated children should be restricted from school or day care, 83% believed misdemeanor charges should be brought.
5% reported misdemeanor charges had been brought; 24% had threatened to do so.
83% believed injunctions should be filed, none had done so.
Bond et al (1999)AustraliaParents of children regularly attending council-run day care in metropolitan area.1722 families with 1779 eligible childrenAdditional welfare payments of $29.30–$175 per week for child care plus 1-time payment of $307 if UTD for all vaccinations.No comparatorViews on intervention.Survey.30% believed incentives should be given to parents for immunizing their child, though many believed the child’s health, not monetary reasons, should be the motivator.
Children <3 y (except 62 who were older), 50% male.~30% believed the decision to immunize would not be affected by intervention.
Bond et al (2002)AustraliaParents of children regularly attending council-run day care in metropolitan area. Children <3 y.1706 families with 1793 eligible childrenAdditional welfare payments of $29.30–$175 per week for child care plus 1-time payment of $307 if UTD for all vaccinations.No comparatorViews on intervention.Survey.~30% believed intervention had not influenced decision to immunize.
4% reported they had kept their children’s vaccinations UTD because they relied on related payments.
Hall et al (2002)AustraliaParents of children <12 y 50% <5 y.50School entry restricted to those UTD for all vaccinations.Range of other interventions to promote vaccinationStated preference for vaccination uptake.Survey; discrete choice modeling.Most respondents preferred vaccination under most scenarios. 31% chose not to vaccinate in all scenarios. Requiring vaccination for school entry increased vaccination preference from 75% to 92%.
Tarrant and Thomson (2008)Hong KongParents of children 6 mo–3 y receiving secondary health care.15Day care and school entry restricted to those UTD for all vaccinations.No comparatorViews on intervention.Semistructured person-centered interviews.Day care and school entry restriction identified as contributing to high vaccination rates within a system of other contributory factors.
  • HBV, hepatitis B; Hib, Haemophilus influenzae B; UTD, up to date.

  • a See Table 3 for additional details.