Effects of Pediatric Asthma
Education on Hospitalizations and
Emergency Department Visits:
A Meta-Analysis
Janet M. Coffman, PhD, Michael D. Cabana, MD, MPH,
Helen A. Halpin, PhD, Edward H. Yelin, PhD
University of California, San Francisco
University of California, Berkeley
Institute for
Health Policy
Studies
June 3, 2007
Background and Rationale
 NHLBI guidelines recommend asthma
education for all patients
 Latest meta-analysis only assessed studies
published prior to 1999
 A number of additional studies have been
published over the past eight years
 Innovations in treatment of asthma
 Dissemination of NHLBI guidelines
2
Research Question
 Compared to usual care, does the provision
of asthma education to children and their
parents reduce
 Asthma ED visits?
 Asthma hospitalizations?
3
Methods
 Research Design: Meta-analysis
 Databases:




Cochrane Database of Systematic Reviews
Cochrane Register of Controlled Trials
PubMed
Cumulative Index of Nursing and Allied Health
Literature (CINAHL)
4
Methods
 Inclusion Criteria
 Enrolled children aged 2-17 years with a clinical
diagnosis of asthma
 Conducted in the United States
 Compared asthma education to usual care
 Included a control or comparison group
 Examined ED visits and/or hospitalizations for
asthma
5
Methods
 Calculated pooled findings for
 Odds of an event


ED visit
Hospitalization
 Mean Number of events


ED visits
Hospitalizations
6
Methods
 Analysis
 Estimated fixed effects models for all outcomes
 Conducted Chi-Square test to determine whether
results of the studies pooled are heterogeneous
 Where results were heterogeneous (i.e., p<0.1 for
Chi-Square test), estimated random effects
models
 Small number of studies precluded performing
meta-regression to explore sources of
heterogeneity
7
Results of Literature Search
 174 abstracts reviewed
 23 articles met the inclusion criteria
 Research design
 19 studies (83%) were RCTs or cluster RCTs
 4 (17%) were nonrandomized studies
8
Study Characteristics
 Demographics: in 16 studies (70%) most of the
children enrolled were low-income
 Target of intervention: 57% provided education to
both children and parents
 Types of education: included individual counseling,
group classes, telephone calls, and educational
computer games
 Types of settings: included outpatient clinics/
physician offices, emergency departments, schools,
and homes
9
Odds of ED Visit
Education vs. Usual Care – Fixed Effects
Odds ratio
(95% CI)
Study
% W eight
Butz
0.71 (0.33,1.52)
6.9
Farber
0.97 (0.30,3.14)
2.5
Guendelman
0.48 (0.16,1.39)
4.5
Harish
0.57 (0.28,1.17)
8.9
JosephMild
0.95 (0.55,1.66)
11.4
JosephModSev
1.12 (0.49,2.57)
4.7
Lukacs
1.21 (0.71,2.08)
10.8
Persaud
0.29 (0.07,1.21)
3.1
Shields
1.49 (0.75,2.95)
6.0
Sockrider
0.62 (0.31,1.23)
9.2
Teach
0.55 (0.38,0.80)
32.0
Overall (95% CI)
0.77 (0.63,0.94)
.1
1
10
Odds ratio
Test of OR = 1: z = 2.61, p = 0.009;
Test of Heterogeneity: χ2 =14.59 (df = 10), p = 0.148
10
Odds of Hospitalization
Education vs. Usual Care – Random Effects
Odds ratio
(95% CI)
Study
% W eight
Butz
0.62 (0.16,2.39)
6.3
Evans1999
0.71 (0.49,1.04)
24.3
Farber
8.79 (0.43,180.63)
1.5
Guendelman
4.07 (0.44,37.50)
2.6
Harish
1.03 (0.47,2.26)
13.4
Lukacs
2.50 (0.96,6.54)
10.4
Morgan
0.76 (0.49,1.15)
22.9
Teach
0.51 (0.29,0.90)
18.8
Overall (95% CI)
0.87 (0.60,1.27)
.1
1
10
Odds ratio
Test of OR = 1: z = 0.70, p = 0.482;
Test of Heterogeneity: χ2 =13.31 (df = 7), p = 0.065
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Mean ED Visits
Education vs. Usual Care – Random Effects
Standardised Mean diff.
(95% CI)
% W eight
Study
Alexander
-1.09 (-2.02,-0.16)
2.0
Bartholomew
0.06 (-0.28,0.40)
8.9
Christiansen
0.10 (-0.53,0.73)
Clark
-0.16 (-0.43,0.12)
10.9
Fireman
-0.78 (-1.58,0.02)
2.6
Harish
-0.44 (-0.79,-0.09)
JosephMild
0.00 (-0.20,0.20)
JosephModSev
-0.06 (-0.43,0.30)
8.3
Kelly
-0.45 (-0.90,0.00)
6.4
La Roche
-0.37 (-1.22,0.47)
2.4
McNabb
-1.09 (-2.24,0.06)
1.4
Morgan
-0.06 (-0.19,0.08)
16.3
Persaud
-0.76 (-1.44,-0.08)
Shields
0.09 (-0.18,0.37)
Overall (95% CI)
-0.17 (-0.31,-0.03)
-3
0
3.9
8.7
13.9
3.4
11.0
3
Standardised Mean diff.
Test of SMD = 0: z = 2.40, p = 0.016;
Test of Heterogeneity: χ2 =24.48 (df = 13), p = 0.027
12
Mean Hospitalizations
Education vs. Usual Care – Random Effects
Standardised Mean diff.
(95% CI)
% W eight
Study
Bartholomew
-0.10 (-0.44,0.24)
26.4
Christiansen
-0.37 (-1.00,0.27)
13.1
Clark
-0.17 (-0.43,0.10)
31.6
Fireman
-0.79 (-1.59,0.01)
9.2
Kelly
-0.77 (-1.23,-0.31)
Overall (95% CI)
-0.35 (-0.63,-0.08)
-3
0
19.7
3
Standardised Mean diff.
Test of SMD = 0: z = 2.53, p = 0.012;
Test of Heterogeneity: χ2 =7.68 (df = 4), p = 0.104
13
Possible Reasons for Heterogeneity
 Although there are not enough studies for
meta-regression, findings for effects on ED
visits appear to differ based on
 Type of education: individual education more
effective than group education
 Setting: providing education in clinical settings
more effective than providing in school
14
Limitations
 Only assessed effects on ED visits and
hospitalizations
 Lack of consistent measures of severity of
asthma symptoms
 Potential publication bias
 Results may not generalize to
 Upper- and middle-income children
 Children outside the USA
15
Conclusions and Implications
 Pediatric asthma education reduces
 Odds of an ED visit
 Mean ED visits
 Mean hospitalizations
 However, in our sample, pediatric asthma education
does not affect odds of hospitalization
 Health plans should provide incentives for pediatric
asthma education
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Thank You
 Co-authors
 Michael D. Cabana, MD, MPH, UCSF
 Edward H. Yelin, PhD, UCSF
 Helen A. Halpin, PhD, UC-Berkeley
 Funders
 California Health Benefits Review Program
 National Institutes of Health (#HL70771)
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QUESTIONS?
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Opportunities for Research



Cost-effectiveness of pediatric asthma
education
Identification of the most important
components of asthma education
Which children benefit most from asthma
education
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Why
Limit Meta-Analysis to US Studies?
•
•
•
•
Interested in effect of pediatric asthma education on
ED visits
ED utilization depends in part on a country’s health
care system
In the US, many low-income children have poor
access to primary care
Including studies from countries with universal
health care may have confounded the results
20
Comparisons of Different
Educational Interventions
 Comparisons of different educational
interventions suggest that greater reductions
in hospitalizations and ED visits were
associated with



More sessions
More comprehensive education
More interactive modes of education
21