BACKGROUND:
Late initiation of infant immunizations was found to be the best predictor of incomplete immunizations among 2-year-olds in Alabama (Henao, 1997). Little is known about how to educate and motivate mothers to begin immunizations on time.

OBJECTIVE:
(1) To describe characteristics of mothers who sought infant immunizations at an urban health department; (2) to determine associations between each of the maternal characteristics described in two sets of variables by the Interaction Model of Client Health Behavior (IMHDB) (Cox, 1982); and (3) to determine the association of maternal characteristics and timely immunization start.

METHOD:
A proportional, stratified quota sample of 154 mothers of neonates was interviewed using the Social Support Questionnaire 6 (Sarason, Sarason, Shearin, & Pierce, 1987), Health Self-Determinism Index (Cox, 1985), Communicable Disease Perceived Vulnerability Scale (Houtrouw & Carlson, 1993; Rosenblum, Stone, & Skipper, 1981), and an investigator-developed instrument. Maternal characteristics were examined using descriptive statistics. Associations among maternal characteristics and timeliness of beginning infant immunizations were tested using bivariate analyses and logistic regressions (alpha <=.05)

RESULT:
Associations were found among maternal age and cognitive appraisal of immunizations, number of children and perceived vulnerability to communicable diseases, number of children and affective response to immunizations, number of prenatal appointments and health self-determinism, and previous experience with immunizations and affective response to immunizations. Timely immunization start was associated with mother's education, number of adults in household, satisfaction with social support, number of prenatal appointments, and cognitive appraisal of immunizations.

CONCLUSION:
(1) Number of prenatal appointments can indicate mothers at risk for late start with infant immunizations. (2) Nurses should assess individual mothers' cognitive appraisal of immunizations and intervene to influence the accuracy of these appraisals.

LEARNING OBJECTIVES:
To gain knowledge about maternal characteristics that are associated with timeliness in beginning infant immunizations and that may be amenable to nursing interventions.