The number of studies and publications do not always correspond (e.g., a publication may include several studies or one study may be explained n several publications).
Ashkar SH, Dales LG, Averhoff F et al. The effectiveness of assessment and referral on immunization coverage in the special supplemental nutrition program for women, infants, and children. Archives of Pediatrics & Adolescent Medicine 2003;157:456-62.
Bardenheier BH, Yusuf HR, Rosenthal J et al. Factors associated with underimmunization at 3 months of age in four medically underserved areas. Public Health Reports 119(5):479-85.
Birkhead GS, LeBaron CW, Parsons P, Grabau JC, Maes E, Barr-Gale L et al. The immunization of children enrolled in the Special Supplemental Food Program for Women, Infants, and Children (WIC). The impact of different strategies. JAMA 1995;274(4):312-31.
Brenner RA, Simons-Morton BG, Bhaskar B, Das A, Clemens JD, NIH DCI. Prevalence and predictors of immunization among inner-city infants: a birth cohort study. Pediatrics 2001;108(3):661-70.
Cortese MM, Diaz PS, Samala U et al. Underimmunization in Chicago children who dropped out of WIC. American Journal of Preventive Medicine 2004;26(1):29-33.
Dietz VJ, Baughman AL, Dini EF, Stevenson JM, Pierce BK, Hersey JC. Vaccination practices, policies, and management factors associated with high vaccination coverage levels in Georgia public clinics. Georgia Immunization Program Evaluation Team. Archives of Pediatrics & Adolescent Medicine 2000;154(2):184-9.
Ghosh TS, Patnaik JL, Bennett A, Trefren L, Vogt RL. Assessment of missing immunizations and immunization-related barriers among WIC populations at the local level. Public Health Rep 2007;122(5):602-6.
Golden R. Voucher incentives to increase childhood immunization rates [comment]. JAMA 1999;281(8):702-3.
Hoekstra EJ, LeBaron CW, Megaloeconomou Y et al. Impact of a large-scale immunization initiative in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) [see comment]. JAMA 1998;280(13):1143-7.
Hoekstra EJ, LeBaron CW, Johnson PT. Does reminder-recall augment the impact of voucher incentives on immunization rates among inner-city infants enrolled in WIC? Special Supplemental Program for Women, Infants, and Children. Journal of Pediatrics 1999;135:261-3.
Hutchins SS, Rosenthal J, Eason P, Swint E, Guerrero H, Hadler S. Effectiveness and cost-effectiveness of linking the special supplemental program for women, infants, and children (WIC) and immunization activities. Journal of Public Health Policy 1999;(4):408-26.
Kendal AP, Neville LJ, Manning CC. Optimal immunization practices for the special supplemental nutrition program for women, infants, and children. American Journal of Public Health 2000;90(10):1640-1.
Shefer AM, Luman ET, Lyons BH et al. Vaccination status of children in the Women, Infants, and Children (WIC) Program: are we doing enough to improve coverage? American Journal of Preventive Medicine 2001;(4 Suppl):47-54.
Shefer AM, Fritchley J, Stevenson J et al. Linking WIC and immunization services to improve preventive health care among low-income children in WIC. Journal of Public Health Management & Practice 2002;8(2):56-65.
Suarez L, Simpson DM, Smith DR. The impact of public assistance factors on the immunization levels of children younger than 2 years. American Journal of Public Health 1997;87(5):845-8.
Waterman SH, Hill LL, Robyn B, Yeager KK, Maes EF, Stevenson JM et al. A model immunization demonstration for preschoolers in an inner-city barrio, San Diego, California, 1992-1994. Am J Prev Med 1996;12(4 Suppl):8-13.
Included Studies - Economic Review
Flatt K, Watson JC, Anderson KN, Logan L, Nguyen V. A cost comparison of methods used to increase immunization levels in a WIC setting. Paper presented at: The 124th annual meeting and exposition of the American Public Health Association, November 17-21. 1996; New York.
Hoekstra EJ, LeBaron CW, Megaloeconomou Y, et al. Impact of a large-scale immunization initiative in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). JAMA 1998;280(13):1143. http://dx.doi.org/10.1001/jama.280.13.1143.
Hutchins SS, Rosenthal J, Eason P, Swint E, Guerrero H, Hadler S. Effectiveness and cost-effectiveness of linking the special supplemental program for women, infants, and children (WIC) and immunization activities. J Public Health Policy 1999:408-26. http://dx.doi.org/10.2307/3343128.
Search Strategy - Economic Review
The present review included studies that reported economic outcomes from the 2000 review (search period 1980-1997) combined with studies identified from updated searches (search period 1997- February 2012) within the standard medical and health-related research databases, Google Scholar, and databases specialized to economics and social sciences. The details of the two sets of searches are provided below.
Details of the Updated Search (1997- February 2012)
The team conducted a broad literature search to identify studies assessing interventions to improve vaccination rates. The following nine databases were searched during the period of 1997 up to February 2012: CABI, CINAHL, The Cochrane Library, EMBASE, ERIC, MEDLINE, PSYCHINFO, Soci Abs and WOS. In addition, Google Scholar and specialized databases (CRD-University of York: NHS EED, EconLit, and JSTOR), were also searched. Reference lists of articles reviewed as well as lists in review articles were also considered, and subject matter experts consulted for additional references.
- Immunization Programs
To be included in the updated review, a study had to do the following:
- Have a publication date of 1997- February 2012
- Evaluate vaccinations with universal recommendations
- Meet the evidence review and Community Guide review team's definition of the interventions
- Be a primary research study with one or more outcomes related to the analytic framework(s)
- Take place in a high income country or countries
- Be written in English; and
- Compare a group of persons who had been exposed to the intervention with a group who had not been exposed or who had been less exposed.
Details of the Original Search (1980-1997)
The following five electronic databases were searched during the original review period of 1980 up to1997: MEDLINE, Embase, Psychlit, CAB Health, and Sociological Abstracts. The team also reviewed reference lists in articles and consulted with immunization experts. To be included, a study had to do the following:
- Have a publication date of 1980–1997
- Address universally recommended adult, adolescent, or childhood vaccinations
- Be a primary study rather than, for example, a guideline or review
- Take place in an industrialized country or countries
- Be written in English
- Meet the definition of the interventions
- Provide information on one or more outcomes related to the analytic frameworks; and
- Compare a group of persons who had been exposed to the intervention with a group who had not been exposed or who had been less exposed. In addition, we excluded studies with least suitable designs for two interventions (provider reminder/recall and client reminder/recall) where the literature was most extensive.