1. Emuella Flood Principal, Oxford Outcomes NIC 2010
Parent's Decision-Making for Immunizing Children against Seasonal Influenza
Emuella Flood
Principal, Oxford Outcomes
NIC 2010
April 21, 2010
Emuella M. Flood, BA 1 Kellie J. Ryan, MPH 2 Stan L. Block, MD 3 Matthew C. Hall, MD 4 Victoria M. Divino, BA 1 Matthew D. Rousculp, PhD, MPH 2 Seth L. Toback, MD 2
1Oxford Outcomes, Bethesda, MD, 2MedImmune LLC, Gaithersburg, MD, 3Kentucky Pediatric Research, Bardstown, Kentucky, 4 Marshfield Clinic, Marshfield, Wisconsin.

2. Disclaimer
This study was conducted with and on behalf of MedImmune.

3. Background
Seasonal influenza is a common illness associated with substantial morbidity among children
ACIP recommends vaccine for children aged 6 mos - 18 yrs 
Vaccination rates during 2008/9 influenza season:1
6-23 mos: 41%
2-4 yrs: 32%
5-17 yrs: 21%
 Parents are primary decision-makers for immunizing children against influenza
1Centers for Disease Control and Prevention [CDC]. Influenza Vaccination Coverage among Children and Adults — United States, 2008–09 Influenza Season. MMWR. 2009; 58:
December 9, 2019

4. Objectives
Explore parental decision-making regarding influenza vaccination for children aged 2 to 12 years
Identify the factors (drivers and barriers) that influence decision-making and quantify their importance
Develop a conceptual model illustrating the factors impacting decision-making
December 9, 2019

5. Methods
Quantitative web survey for parents of children aged 2-12 years
Based on qualitative study and key opinion leader input
Parents sampled from survey panel between Aug-Sep 2009
Panel representative of US population
Stratified by influenza vaccination rate of parent (yearly, sometimes, never) and age of child (2-4 yrs, 5-12 yrs)
December 9, 2019

6. Methods/ Survey Content
Experience and perceptions of influenza / influenza vaccine
Selection of factors (drivers and barriers) influencing decision-making and rating importance of factors
Pre-defined list of 19 drivers and 13 barriers
5-point scale: 1=a little important to 5=extremely important
Rating of agreement with statements regarding beliefs and perceptions about influenza and influenza vaccine
5-point scale: 1=strongly agree to 5=strongly disagree
December 9, 2019

7. Methods/ Analysis
Calculated frequencies and mean importance/agreement ratings
Examined differences across subgroups
Likelihood of vaccinating child for influenza next year
high, medium, low
never (n=18) excluded from analysis
Socio-demographic variables
age of child, sex of parent, income, education, and race/ethnicity
Significance tests including:
Chi-square for frequencies between subgroups
Student’s t-test for means between two subgroups
Analysis of variance for means between three or more subgroups
December 9, 2019

8. Results/ Parent Sample
Parent Sample Characteristics
Total N=500
Age (years)
Mean (SD)
Median
Min, Max
37.4 (6.8) 37
22, 68
Sex
Male
Female
214 (43%)
286 (57%)
Racial/Ethnic Background
White, Non-Hispanic
Black, Non-Hispanic
Other, Non-Hispanic
Hispanic
2+ Races, Non-Hispanic
391 (78%)
20 (4%)
21 (4%)
49 (10%)
19 (4%)
Highest Level of Education Completed
Less than high school
High school
Some college
College degree
Graduate degree
103 (20%)
129 (26%)
153 (31%)
96 (19%)
December 9, 2019

9. Results/ Child Sample Total N=500 Child Sample Characteristics
Age (years)
2 - 4
5 -12
234 (47%)
266 (53%)
Sex
Male
Female
256 (51%)
243 (49%)
Co-morbidities
Asthma
Allergies
Diabetes
Other
43 (9%)
107 (21%)
4 (1%)
38 (8%)
Ever had the flu
Yes No
Don’t know
172 (35%)
280 (56%)
47 (9%)
Ever received a flu vaccine
312 (63%)
171 (34%)
15 (3%)
December 9, 2019

10. Results/ Influenza Vaccination Behavior
Flu Vaccination Behavior
Total N=500
Parent’s personal flu vaccination behavior
Every year
Sometimes
Never
197 (40%)
141 (28%)
162 (32%)
Flu vaccination behavior for child
219 (44%)
107 (22%)
170 (34%)
Likelihood of vaccinating child for flu next year
High
Medium
Low
Would never
241 (48%)
106 (21%)
135 (27%)
18 (4%)
December 9, 2019

11. Frequency selected n (%)
Results/ Top Drivers
Parents who vaccinate child for influenza every year or sometimes (N=326)
Driver
Frequency selected n (%)
Mean Importance (SD)*
To prevent my child from getting the seasonal flu
308 (95.1%)
4.37 (0.82)
The doctor recommended it
289 (89.5%)
3.68 (0.98)
To reduce the symptoms of the flu if my child was to get the seasonal flu
270 (83.3%)
4.20 (0.91)
To avoid spreading the seasonal flu to others
199 (62.2%)
3.76 (0.92)
It’s routine; I always have my child vaccinated for the flu
199 (61.6%)
3.52 (1.13)
It was convenient; it was offered at a regularly scheduled doctor visit
185 (58.0%)
3.43 (1.07)
*Scores reflect range from 1 – 5, with 1= A Little Important and 5= Extremely Important ; mean importance among those who gave an importance rating ; missing data < 3%; missing data excluded
December 9, 2019

12. Frequency selected n (%)
Results/ Top Barriers
Parents who vaccinate their child for influenza sometimes or never (N=277)
Barrier
Frequency selected n (%)
Mean Importance (SD)*
My child had a low chance of getting the seasonal flu
126 (46.0%)
3.22 (1.00)
The seasonal flu vaccine can cause the flu
120 (44.0%)
3.50 (1.08)
The seasonal flu vaccine causes side effects (like runny nose/nasal congestion or sore arm)
100 (36.6%)
3.28 (1.00)
The seasonal flu is not that serious
92 (33.7%)
2.97 (1.04)
The seasonal flu vaccine does not work well
91 (33.1%)
3.40 (0.99)
The seasonal flu vaccine contains Thimerosal (mercury-containing preservative)
90 (32.9%)
4.20 (1.00)
Barriers were highly variable, and had lower frequency of endorsement and lower importance ratings compared to drivers
*Scores reflect range from 1 – 5, with 1= A Little Important and 5= Extremely Important ; mean importance among those who gave an importance rating ; missing data < 3%; missing data excluded
December 9, 2019

13. Frequency endorsed n(%) Frequency endorsed n(%)
Results/ Top Drivers by Likelihood of Vaccinating Child for Influenza Next Year
Top Drivers for High Likelihood N= Top Drivers for Medium Likelihood N=71
Driver
Frequency endorsed n(%)
Mean Importance (SD)
To prevent my child from getting the seasonal flu
224 (98%)
4.54 ( 0.75)
The doctor recommended it
202 (89%)
3.76 (0.95)
To reduce the symptoms of flu if my child was to get the seasonal flu
195 (86%)
4.35 (0.86)
It’s routine; I always have my child vaccinated for the flu
180 (79%)
3.56 (1.16)
To avoid spreading the seasonal flu to others
153 (68%)
3.86 (0.91)
Driver
Frequency endorsed n(%)
Mean Importance (SD)
To prevent my child from getting the seasonal flu
65 (93%)
4.02 (0.80)
The doctor recommended it
3.52 (0.94)
To reduce the symptoms of flu if my child was to get the seasonal flu
60 (85%)
4.02 (0.79)
It was convenient; it was offered at a regularly scheduled doctor visit
49 (71%)
3.53 (0.82)
To avoid spreading the seasonal flu to others
39 (57%)
3.46 (0.91)
Prevention of influenza, doctor’s recommendation, and reduction in influenza symptoms were the three most commonly endorsed drivers for both the medium and high likelihood groups; highest mean total importance ratings for both
High likelihood parents more likely to endorse the idea of a social contract – to avoid spreading the seasonal influenza to others, and were more likely to endorse these drivers vs. medium and low likelihood parents
Most people I know vaccinate their children for the seasonal flu (32% vs. 26% and 15%)
To avoid spreading the seasonal flu to others (68% vs. 57% and 27%)
Scores reflect range from 1 – 5, with 1= A Little Important and 5= Extremely Important *
December 9, 2019

14. Frequency selected n (%) Frequency selected n (%)
Results/ Top Barriers by Likelihood of Vaccinating Child for Influenza Next Year
Top Barriers for Medium Likelihood N=93
Top Barriers for Low Likelihood N=132
Barrier
Frequency selected n (%)
Mean Importance (SD)
The seasonal flu vaccine can cause the flu
39 (42%)
3.59 (1.07)
Getting the seasonal flu vaccine was not convenient
36 (39%)
3.03 (1.25)
The seasonal flu vaccine causes side effects (like runny nose/nasal congestion or sore arm)
33 (36%)
3.30 (0.95)
My child had a low chance of getting the seasonal flu
31 (33%)
2.77 (0.92)
Barrier
Frequency selected n (%)
Mean Importance (SD)
My child had a low chance of getting the seasonal flu
75 (58%)
3.36 (0.94)
The seasonal flu vaccine can cause the flu
64 (50%)
3.38 (1.06)
The seasonal flu is not that serious
57 (44%)
2.98 (0.97)
The seasonal flu vaccine does not work well
53 (40%)
3.32 (0.80)
Parents with a low likelihood of vaccinating their child against influenza endorsed barriers at a higher frequency compared to parents with a medium likelihood
Scores reflect range from 1 – 5, with 1= A Little Important and 5= Extremely Important
December 9, 2019

15. Results/ Perceived Severity by Likelihood of Vaccinating Child for Influenza Next Year
Perception of severity of influenza increased with parents’ likelihood of vaccinating their child for influenza
More parents in the high likelihood category responded death was the worst thing that could happen to their child if he/she gets influenza, compared to those in the medium and low likelihood groups (50%, 32%, and 31%, respectively); Most low likelihood parents reported staying in bed for 3 days (37%)
(not in slide) Majority of parents across three likelihood categories thought influenza would be moderate in severity for their child but a greater proportion of parents in the high likelihood group perceived severity to be severe or very severe compared to parents in the medium and low likelihood groups (24%, 13%, and 3%, respectively)
December 9, 2019

16. Results/ Perceived Susceptibility by Likelihood of Vaccinating Child for Influenza Next Year
Perception of susceptibility to influenza increased with parents’ likelihood for vaccinating their child for influenza next season
High likelihood parents were more likely to indicate that influenza is very or extremely contagious compared to medium and low likelihood parents (80%, 58%, and 50%, respectively)
(not in slide) The majority of low likelihood parents (68%) reported that their child had a low or very low chance of getting influenza next season, whereas the majority of high and medium likelihood parents reported their child had a medium chance of influenza (63% and 69%, respectively)
(not in slide) While most parents in each group responded that in general, some children get influenza, a greater percentage of parents in the high likelihood group believed that many children get influenza compared to those in the medium and low likelihood groups (44%, 34%, and 28%, respectively)
December 9, 2019

17. Results/ Characterizing Parents by Likelihood of Vaccinating Child for Influenza
High likelihood
Perceive greater threat of influenza
Believe in efficacy and safety of vaccine and importance of social contract
Low likelihood
Expressed least concern regarding threat of influenza and most concern over safety and efficacy of vaccine
More likely to believe in benefits of ‘natural immunity’
Medium likelihood
Mixed perceptions regarding efficacy and safety of influenza vaccine
Convenience is important factor
December 9, 2019

18. Conceptual Model of Parent Decision-making
Based on our findings the Health Belief Model (HBM) was identified as optimal framework2
HBM is most commonly used theoretical model to explain health behavior
Used as framework for a number of studies exploring disease prevention and screening behavior including vaccination
In the HBM, health behavior is determined by four main constructs:
Perceived seriousness or severity of a disease
Perceived susceptibility or risk of acquiring the disease
Perceived benefits of the behavior
Perceived barriers or obstacles to adopting the behavior
2Glanz K, Rimer B, Lewis F. Health Behavior and Health Education, Theory, Research, and Practice. Jossey-Bass publishers 2002, 3rd edition.
December 9, 2019

19. Results/ Conceptual Model of Parent Decision-making
December 9, 2019

20. Conclusions
Parents who believe their child is at high risk of influenza and/or believe influenza is a severe disease have a higher reported likelihood of vaccinating their child against influenza
Parents of children aged 2 to 12 yrs can be categorized into three distinct groups based on their likelihood of immunizing their children (high, medium, low)
Relative importance of perceived benefits and barriers varies across these groups
Prevention of flu, reduction of flu symptoms and doctor recommendation were overwhelmingly selected as drivers for flu vaccination
Barriers to vaccination were more variable; primary reasons included risk of adverse events and perceived low risk of flu 
December 9, 2019

21. Conclusions
Health care providers should consider these barriers and drivers when addressing low influenza vaccination rates for children
Among medium likelihood parents, education efforts to increase awareness of the safety and efficacy of influenza vaccines, as well as to provide vaccine opportunities that are convenient for parents may help to improve vaccination rates
Among low likelihood parents, education efforts to increase awareness of the severity of influenza illness as well as the efficacy and safety of influenza vaccine may help to improve vaccination rates
December 9, 2019