Identifying Infants at Increased Risk for Late Initiation of Immunizations: Maternal and Provider Characteristics

Abstract

Objective.

We identified maternal, provider, and community predictors among infants for late initiation of immunizations.

Methods.

We performed a retrospective cohort study of infants born between January 1, 2002, and December 31, 2004, in Philadelphia, Pennsylvania. Primary outcomes were age in days at first office-based immunization and status as a late starter (i.e., initiating office-based immunizations after 90 days of age). Candidate predictors included sociodemographic and prenatal characteristics, immunization provider practice type and size, and neighborhood factors. We performed hierarchical logistic regression and Cox regression models to identify independent predictors for being a late starter and prolonged time to first immunization.

Results.

Of the 65,519 infants from this birth cohort in Philadelphia's immunization registry, 54,429 (88.1%) were included in analysis and 12.6% of these were late starters. Infants whose mothers were younger, received less than five prenatal visits, had less than a high school education, had more than two children, and who smoked cigarettes prenatally were significantly more likely to be late starters. Receiving care at hospital/university-based or public health clinics was also significantly associated with likelihood of being a late starter. Neither distance between infant's residence and practice nor neighborhood socioeconomic indicators was independently associated with the outcomes. Common risk factor profiles based on practice type and four maternal characteristics were found to reliably identify infant risk.

Conclusions.

Maternal receipt of fewer prenatal care visits, younger maternal age, higher birth order, and receiving care at public health clinics were the strongest predictors of being a late starter and time to first immunization. Risk factor profiles based on information already collected at birth can be used to identify higher-risk infants. Early intervention and potentially partnering with prenatal care providers may be key strategies for preventing underimmunization.

References

Luman

Barker

McCauley

Drews-Botsch

Timeliness of childhood immunizations: A state-specific analysis. Am J Public Health 2005;95:1367–74.

Luman

Barker

Shaw

McCauley

Buehler

Pickering

. Timeliness of childhood vaccinations in the United States: Days undervaccinated and number of vaccines delayed. JAMA 2005;293:1204–11.

Dombkowski

Lantz

Freed

. The need for surveillance of delay in age-appropriate immunization. Am J Prev Med 2002;23:36–42.

Chilkatowsky

. Immunization coverage levels among Philadelphia children 19–35 months of age. Philadelphia Immunization Coalition Meeting. Philadelphia: Philadelphia Department of Public Health Division of Disease Control; 2005.

Fiks

Alessandrini

Luberti

Ostapenko

Zhang

Silber

. Identifying factors predicting immunization delay for children followed in an urban primary care network using an electronic health record. Pediatrics 2006;118:e1680–6.

Bardenheier

Yusuf

Rosenthal

Santoli

Shefer

Rickert

, Factors associated with underimmunization at 3 months of age in four medically underserved areas. Public Health Rep 2004;119:479–85.

Brenner

Simons-Morton

Bhaskar

Das

Clemens

. Prevalence and predictors of immunization among inner-city infants: A birth cohort study. Pediatrics 2001;108:661–70.

Bates

Wolinsky

. Personal, financial and structural barriers to immunization in socioeconomically disadvantaged urban children. Pediatrics 1998;101(4 Pt 1):591–6.

Williams

Milton

Farrell

Graham

. Interaction of socioeconomic status and provider practices as predictors of immunization coverage in Virginia children. Pediatrics 1995;96(3 Pt 1):439–46.

10.

Wood

Donald-Sherbourne

Halfon

Tucker

Ortiz

Hamlin

, Factors related to immunization status among inner-city Latino and African-American preschoolers. Pediatrics 1995;96(2 Pt 1):295–301.

11.

Guyer

Hughart

Holt

Ross

Stanton

Keane

, Immunization coverage and its relationship to preventive health care visits among inner-city children in Baltimore. Pediatrics 1994;94:53–8.

12.

Freed

Clark

Pathman

Schectman

Influences on the receipt of well-child visits in the first two years of life. Pediatrics 1999;103:864–9.

13.

Hambidge

Davidson

Phibbs

Chandramouli

Zerbe

LeBaron

, Strategies to improve immunization rates and well-child care in a disadvantaged population: A cluster randomized control trial. Arch Pediatr Adolesc Med 2004;158:162–9.

14.

Meyerhoff

Jacobs

. Do too many shots lead to missed vaccination opportunities? Does it matter? Prev Med 2005;41:540–4.

15.

Daniels

Jiles

Klevens

Herrera

. Undervaccinated African-American preschoolers: A case of missed opportunities. Am J Prev Med 2001;20(4 Suppl):S61–8.

16.

Dayan

Shaw

Baughman

Orellana

Forlenza

Ellis

, Assessment of delay in age-appropriate vaccination using survival analysis. Am J Epidemiol 2006;163:561–70.

17.

Hambidge

Phibbs

Davison

LeBaron

Chandramouli

Fairclough

, Individually significant risk factors do not provide an accurate clinical prediction rule for infant underimmunization in one disadvantaged urban area. Ambul Pediatr 2006;6:165–72.

18.

Taylor

Darden

Slora

Hasemeier

Asmussen

Wasserman

The influence of provider behavior, parental characteristics and a public policy initiative on the immunization status of children followed by private pediatricians: A study from pediatric research office settings. Pediatrics 1997;99:209–15.

19.

Steyer

Mainous

III Geesey

. The effect of race and residence on the receipt of childhood immunizations: 1993–2001. Vaccine 2005;23:1464–70.

20.

Bates

Fitzgerald

Dittus

Wolinsky

. Risk factors for underimmunization in poor urban infants. JAMA 1994;272:1105–10.

21.

Ross

Kennedy

Holt

Guyer

Hou

Hughart

Initiating the first DTP vaccination age-appropriately: A model for understanding vaccination coverage. Pediatrics 1998;101:970–4.

22.

Kogan

Alexander

Jack

Allen

. The association between adequacy of prenatal care utilization and subsequent pediatric care utilization in the United States. Pediatrics 1998;102:25–30.

23.

Strobino

Keane

Holt

Hughart

Guyer

Parental attitudes do not explain underimmunization. Pediatrics 1996;98(6 Pt 1):1076–83.

24.

Wiecha

Gann

Does maternal prenatal care use predict infant immunization delay?

Fam Med 1994;26:172–8.

25.

Luman

McCauley

Shefer

Chu

. Maternal characteristics associated with vaccination of young children. Pediatrics 2003;111(5 Pt 2):1215–8.

26.

Kolasa

Chilkatowsky

Clarke

Lutz

. How complete are immunization registries? The Philadelphia story. Ambul Pediatr 2006;6:21–4.

27.

ESRI, Inc. ArcView, ArcMap: Version 9.1. Redlands (CA): ESRI, Inc.; 2006.

28.

Census Bureau (US). U.S. Census 2000 [cited 2008 Aug 18]. Available from: URL: http://www.census.gov.

29.

Austin

Goel

van Walraven

An introduction to multilevel regression models. Can J Public Health 2001;92:150–4.

30.

Yau

. Multilevel models for survival analysis with random effects. Biometrics 2001;57:96–102.

31.

Shui

Weintraub

Gust

. Parents concerned about vaccine safety: Differences in race/ethnicity and attitudes. Am J Prev Med 2006;31:244–51.

32.

Gust

Kennedy

Shui

Smith

Nowak

Pickering

. Parent attitude toward immunizations and healthcare providers: The role of information. Am J Prev Med 2005;29:105–12.

33.

Gust

Strine

Maurice

Smith

Yusuf

Wilkinson

, Underimmunization among children: Effects of vaccine safety concerns on immunization status. Pediatrics 2004;114:e16–22.

34.

Kennedy

Brown

Gust

. Vaccine beliefs of parents who oppose compulsury vaccination. Public Health Rep 2005;120:252–8.

35.

Mills

Montori

Ross

Shea

Wilson

Guyatt

. Systematically reviewing qualitative studies complements survey design: An exploratory study of barriers to paediatric immunisations. J Clin Epidemiol 2005;58:1101–8.

36.

Benin

Wisler-Scher

Colson

Shapiro

Holmboe

. Qualitative analysis of mothers' decision-making about vaccines for infants: The importance of trust. Pediatrics 2006;117:1532–41.

37.

Chen

Wen

Fleming

Demissie

Rhoads

Walker

Teenage pregnancy and adverse birth outcomes: A large population-based retrospective cohort study. Int J Epidemiol 2007;26:368–73.

38.

Klein

; American Academy of Pediatrics Committee on Adolescence. Adolescent pregnancy: Current trends and issues. Pediatrics 2005;116:281–6.

39.

Morrow

Rosenthal

Lakkis

Bowers

Butterfoss

Crews

, A population-based study of access to immunization among urban Virginia children served by public, private, and military health care systems. Pediatrics 1998;101:e5.

40.

Diez-Roux

Kiefe

Jacobs

Jr Haan

Jackson

Nieto

, Area characteristics and individual-level socioeconomic position indicators in three population-based epidemiologic studies. Ann Epidemiol 2001;11:395–405.

41.

Subramanian

Chen

Rehkopf

Waterman

Krieger

Comparing individual- and area-based socioeconomic measures for the surveillance of health disparities: A multilevel analysis of Massachusetts births, 1989–1991. Am J Epidemiol 2006;164:823–34.

42.

Winkleby

Cubbin

Ahn

Low individual socioeconomic status, neighborhood socioeconomic status, and adult mortality. Am J Public Health 2006;96:1–9.

43.

Santoli

Barker

Lyons

Gandhi

Phillips

Rodewald

. Health department clinics as pediatric immunization providers: A national survey. Am J Prev Med 2001;20:266–71.

44.

Smith

Stevenson

Chu

. Associations between childhood vaccination coverage, insurance type, and breaks in health insurance coverage. Pediatrics 2006;117:1972–8.

45.

Allred

Wooten

Kong

The association of health insurance and continuous primary care in the medical home on vaccination coverage for 19- to 35- month-old children. Pediatrics 2007;119 Supp1 1:S4–11.

46.

Smith

Santoli

Chu

Ochoa

Rodewald

. The association between having a medical home and vaccination coverage among children eligible for the Vaccines for Children program. Pediatrics 2005;116:130–9.

47.

Lauderdale

Oram

Goldstein

Daum

. Hepatitis B vaccination among children in inner-city public housing, 1991–1997. JAMA 1999;282:1725–30.

48.

Seal

Daum

. What happened to primum non nocere? Pediatrics 2001;107:1177–8.

49.

Shete

Daum

. Real versus theoretical: Assessing the risks and benefits of postponing the hepatitis B vaccine birth dose. Pediatrics 2002;109:701–3.

50.

Freeman

DeFriese

. The challenge of potential of childhood immunization registries. Annu Rev Public Health 2003;24:227–46.

51.

Bartlett

Molinari

Ortega-Sanchez

Urquhart

. Economics of immunization information systems in the United States: Assessing costs and efficiency. Cost Eff Resour Alloc 2006;4:15.

52.

Serwint

Wilson

Vogelhut

Repke

Seidel

. A randomized controlled trial of prenatal pediatric visits for urban, low-income families. Pediatrics 1996;98(6 Pt 1):1069–75.