1. Physician Adoption of Adolescent Tdap Recommendations
Mandy Dempsey, MD, PhD, MPH
CHEAR Unit, Dept of Pediatrics
University of Michigan
NIC, 2008

2. Pertussis
Pertussis is one of the only VPDs with an increasing incidence
Adolescents at high risk of contracting illness and are a main reservoir of infection

3. Tdap Vaccines
In 2005, two vaccines combing tetanus, diphtheria and acellular pertussis antigens were licensed
ACIP recommended all adolescents ages years receive Tdap instead of Td booster

4. Previous Study of Physician Attitudes
2005 survey of FP and PD to inform ACIP deliberations about Tdap
Moderate support for replacing adolescent Td with Tdap
FPs less enthusiastic about the vaccine that PDs
Lack of adolescent visits identified as potential barrier to Tdap administration

5. Research Objectives
Determine physician practices regarding uptake of adolescent Tdap recommendations
Evaluate whether specialty-based disparities in attitudes and practices regarding Tdap still exist

6. Study Sample
National random sample of 725 FP and 725 PD from AMA master file
Exclusions
>70 years old
Residents
Providing care at federal facilities (e.g. VA)
No outpatient adolescent care
Not in active practice

7. Study Design Mail-based survey 3 mailings – Jan-March, 2007
Utilization patterns, attitudes, barriers to stocking and administration, use with MCV4, acceptable intervals between Tdap and Td
3 mailings – Jan-March, 2007
$5 incentive

8. Analytic Methods Descriptive statistics Chi-squared analyses
Multivariable logistic regression

9. Results – Response Rate
287 surveys excluded
702 returned – 60%
53% FP
68% PD
Gender, age, medical degree, geographic area, yrs since graduation similar between NR and R

10. Respondent Characteristics
All (n=702)
FP (n=302)
PD (n=400)
Age
<35
>50 8%
36% 9%
38% 7%
35%
Yrs since graduation
<10
>25
18%
28%
20%
24%
17%
31%
Proportion adolescent patients*
<10%
10-25%
>25%
16%
70%
14%
27% 3%
69%
23%
Previous experience w/adolescent pertussis*
Never
1-5 times
≥6 times
33%
45%
22%
46%
41%
13%
48%
39%
* Significant difference between medical specialties, p<.0001

11. Tdap Recommendation Patterns
Frequency of Recommendation
All Respondents
(n=702) FP
(n=302) PD
(n=400)
p-value
11-12 year old adolescents without previous Td booster
Routinely
87%
75%
96%
<.0001
Sometimes 7%
12% 3%
Rarely/never 6%
13% 1%
year old adolescents without previous Td booster
89%
80%
10% 5%

12. Physician Characteristics Associated with Routinely Recommending Tdap, Bivariate
p-value
Professional Society membership No
Yes
77%
90%
.0003
Stock Tdap in the practice
44%
92%
<.0001
Medical Specialty FP PD
75%
96%
Previous diagnostic experience for adolescent pertussis
Never
1-5 times
≥ 6 times
79%
89%
94%
.0002
*11-12 year olds

13. Routinely Recommending Tdap
Not associated with:
Practice size
Practice affiliation
Number of outpatients/week
% adolescent patients

14. Physician Characteristics Associated with Routinely Recommending Tdap, MultivariateOR
95% CI
p-value
Professional Society membership No
Yes
Ref
1.68 -
.1130
Stock Tdap in the practice
7.99
<.0001
Medical Specialty FP PD
4.83
Previous diagnostic experience for adolescent pertussis
Never
1-5 times
≥ 6 times
1.19
2.00
.5598
.1285
*11-12 year olds

15. Tdap following Td Minimal Acceptable Time Interval All (n=702)
FP (n=302)
PD (n=400)
At least 5 years
48%
57%
42%
At least 2 years
44%
39%
<2 years under special conditions 5% 2% 7%
Don’t know 3%
p =.0006

16. Co-administration with Menactra
90% of physicians* would co-administer Tdap with Menactra
95% PD vs. 81% FP (p<.0001)
Of those that would not co-administer (n=61)
43% would wait 1 month between
30% would wait “no specific amount of time”
* Among physicians that stocked Tdap in their practice

17. Stocking Tdap 90% of physicians stocked some form of Tdap 49% Adacel®
15% Boostrix®
15% Both
21% Unsure

18. Characteristics Associated with Stocking Tdap
% Physician Practices Stocking Tdap
p-value
Medical Specialty FP PD
79%
98%
<.0001
Professional Society Membership No
Yes
75%
93%
Previous diagnostic experience with adolescent pertussis
Never
1-5 times
≥ 6 times
82%
95%

19. Characteristics Associated with Stocking Tdap, cont’d
% Physician Practices Stocking Tdap
p-value
Practice size
1 physician
2-4 physicians
5-9 physicians
≥10 physicians
76%
88%
96%
95%
<.0001
Practice Offers Public Stock of Vaccines in General No
Yes
84%

20. Stocking Tdap Not associated with: Practice affiliation
Number of outpatients/week
% adolescent patients

21. Barriers to Administering* Tdap
Major Barrier
Minor Barrier
Not at Barrier
Lack of adolescent visits
33%
37%
30%
Too busy/other priorities during visits 2%
18%
80%
Tdap supply problems
12%
32%
56%
Reimbursement/coverage 8%
25%
67%
Record keeping/knowing who needs Tdap 4%
71%
* Among physicians who stock Tdap in their practices

22. Barriers to Stocking Tdap among Non-stocking Physicians
Low volume adolescent patients (41%)
Increased cost of Tdap relative to Td (39%)
Inadequate reimbursement (31%)

23. Conclusions
ACIP recommendations for adolescent Tdap have been largely adopted by PD and FPs
Most physicians routinely recommend Tdap to year olds as well as older adolescents
Specialty-based differences in vaccination practices persist

24. Conclusions, cont’d
Stocking Tdap in the practice was an important predictor of routinely recommending Tdap
Lack of adolescent visits persists as a perceived barrier to vaccination

25. Limitations Response bias
Respondents may be inherently more interested in immunization issues

26. Implications
Ongoing need to educate providers, particularly FPs, about the need for Tdap vaccination
Education should include information on incorporation of Tdap with other adolescent vaccines, and acceptable intervals following Td
Addressing practice-level barriers such as the ability to stock vaccine in the office may improve adolescent vaccination rates

27. THANK YOU!