public thesis defense
TRANSCRIPT
Effects of theory-based nutrition
intervention using learner-
centered activities on bone health
knowledge, intent, and influences
of school-age children
Nicole Arcilla, B.S.
Julia Casey, B.S.
Casey Mitchell, B.S.
Lauren Simmons, B.S.
Elilta Tsegai, B.S.
Thesis advisor: Karen Plawecki, PhD, RD, LDN
Agenda
• Background: A Review of Bone Health
• Methods
• Demographics
• Results and Discussion
• Strengths, Limitations, and Future
Implications
Background:
A Review of Bone Health
Calcium Overview
• Key nutrient in the
human body and
most abundant
mineral found in the
human body.
• 90% of total body
calcium is stored in
bones and teeth.
• Metabolism and level
is controlled by the
kidneys, bones, and
gastrointestinal tract.
Bass, 2006; Bronner, 2003; http://courses.washington.edu
Calcium Intake
• Recommended amount: – 4-8 years: 1000 mg
– 9-13 years: 1300 mg
• Other sources
• 77% of children ages 9-19 years do not meet the recommended amount of 3 servings/day
(Berner, 2013)
Vitamin D Overview
• Two major forms
– Vitamin D2 or
ergocalciferol
– Vitamin D3 or
cholecalciferol
• Key nutrient for
bone growth and
maintenance
(Misra et al, 2008; Holick et al, 2004; Ross et al,
2011)
Cutaneous Vitamin D
Synthesis• Affected by
– Skin pigmentation• African American children have
increased rates of vitamin D deficiency
– Decreased time outdoors• Specifically the pediatric
population
– UV protection• Encourage “sensible sun
exposure”
– Season• Decreased sun exposure during
winter months
– Latitude • As latitude increases, UV
radiation decreases
(Bose et al, 2013; Au et al, 2014; Misra et al, 2008; Holick et al 2006, www.foodandhealth.com)
Vitamin D Intake
• Breastfed infants
– The American Academy of Pediatrics
recommends 400 IU of vitamin D daily
• Natural versus fortified food
sources
(Economos et al, 2014; Calvo et al, 2004; Wagner et al, 2008; Misra et al, 2008)
Bone Overview
• Skeletal system role
– Movement
– Protection &
Support
– Mineral Reservoir
• Development Stages
– Bone growth
– Bone modeling
– Bone remodeling
(Ralston, 2006; Little, 2011; www.harvard-wm.org 2014)
Bone Remodeling
(Ralston, 2006)
Bone Lifespan
(Betts et al, 2013)
Rickets Disease
• Most common form nutritional rickets
affects children and adolescents
• Maternal vitamin D stores influence
fetal bone development
• Common symptoms
– Bossing of forehead
– Bowed legs
– Impaired growth
(Namgung, 2003; Haliloglu, 2011; Mulligan, 2010; Upton, 2010)
Bone Health Disease
• Adult bone disease
– Osteomalacia
– Osteoporosis
• Currently over 200 million people
diagnosed osteoporosis worldwide
– 10.2 million in the United States
– 43.4 million low bone mass
(osteopenia)
(American Academy Orthopedic Surgeons, 2009; WHO, 2007)
(The Osteoporosis Center, 2014)
Physical Activity
(CDC, 2011; National Institute of Arthritis and Musculoskeletal and Skin Diseases, 2014)
• Recommendations
– 60 minutes or more of age-appropriate
moderate to vigorous-intensity
» In 2011, only 18.5% of girls and 38.3% of
boys achieved this
Types of Exercises
• Aerobic Activity
• Muscle Strengthening
• Bone Strengthening
Miketnelson.blogspot.com
Bone Strengthening Activity
•Weight-bearing
•Running, basketball,
dancing
•Resistance training
•Resistance bands,
free weights, weight
machines
(Lee, 2007; Turner, 2006; Eid, 2014; pennmedicine.org)
Related Literature
•Creighton et al, 2001•Examined BMD and markers of bone
formation
•41 college-aged female athletes•High impact: basketball and volleyball
•Medium impact: track and soccer
•Non-impact: swimming
•High impact group had significantly
higher total body BMD
Mechanism
(Bonnet, 2010)
Related Literature
•Adami et al, 2008•Examined bone formation markers
•24 health sedentary women
•90 minute exercise sessions 3-4x weekly
•Significant increase in bone formation
markers•Even minor changes in PA have positive
effect on bone formation
Theories
• Used to guide and build foundation of programs
• Formation of decision making process
• Identifying measurement indicators
• Commonly used theories:
– Cognitive Behavioral Therapy
– Health Belief Model
– Social Cognitive Theory
– Theory of Planned Behavior
Theories: A Review
• Cognitive Behavioral Therapy
– Exploring emotions and attitudes
towards a behavior
– Meanings individuals may give to
situations or emotions
(Beck, 1976; www.hpft.nhs.uk)
Theories: A Review
• Health Belief Model
– Central focus: Motivation
Individual’s belief on their susceptibility
+
Perceived benefit of change
Willingness and readiness to take action
(Rosenstock et al, 1988)
Theories: A Review
• Social Cognitive Theory
– Ongoing process between 3 main factors:
• Personal, Environmental, Human
behavior
– All factors continuously influence each other
(Bandura, 1986; mellbandura.com)
Theories: A Review
• Theory of Planned Behavior
– Relationship between an individual’s
behavior and beliefs, attitudes, and
intentions.
– Most important determinant: intention
(Azjen et al, 1991; sphweb.bumc.bu.edu)
Application to Batter Up for
Bone Health
• Behavioral theories inappropriate for
intervention’s time frame
• Focusing on Social Cognitive
Theory
– Determining participants’ motivational
and influencing factors
– Understanding lifestyle habits
Background Summary
• Calcium and vitamin D intake
• Bone biology
• Physical activity
• Theory focused
Methods
Study Objectives
• The Batter Up for Bone
Health program aimed to
increase bone health
knowledge and bone
health behaviors in target
population
• Promote bone health
related foods and
activities in children ages
5-13 years
Survey Tools
• Demographic
Survey
• Consent Forms
• Test Surveys
– Pre-test
– Post-test
– 21-day
post-test
Test Survey Format
• Pre-test
– 21 questions
– Food & activity knowledge
– Influences
• Post-test & 21-day post-test
– 19 questions
– Motivation & knowledge changes
Data Analysis
• Descriptives
– Gender
– Age
– Ethnicity
– Camp location
• Hypothesis & Inferential Testing
– Wilcoxon Signed Ranks
– Spearman rho Correlation
– Chi-Square Goodness of Fit
– Friedman
– Kruskal-Wallis
– Mann-Whitney U
Camper Characteristics
Demographics
• Demographic Survey
– Age
– Gender
– Ethnicity
– Calcium use
– Supplement use
Total
Collected
Total with
consent
204 117
Camper Age and Age Group
Category
5-7 Years25%
8-13 Years75%
Age Group Category
5-7 Years
8-13 Years
Age Category N*
5-7 years 19
8-13 years 58
Total 77
Average Camper Age 9.12 ± 2.01
* Reflects those who provided consent forms
Camper Gender
Male49%Female
51%
Gender
Male
Female
Gender N
Female 60
Male 57
Total 117
Camp Location
Elmhurst43%
West Chicago
57%
Camp Location
Elmhurst
WestChicago
Camp Location N
Elmhurst 50
West Chicago 67
Total 117
Camper Ethnicity
Hispanic
44%White42%
Other14%
Ethnicity
Hispanic
White
Other
Ethnicity N
Hispanic 34
White 32
Other 11
Total 77
Camper Ethnicity by Location
White80%
Hispanic0%
Other20%
Elmhurst
White
Hispanic
Other
White0%
Hispanic92%
Other 8%
West Chicago
White
Hispanic
Other
Camper Calcium Use
65
27
3 1 1
49 46
20
10
20
30
40
50
60
70
Fre
qu
en
cie
s
Responses
Frequency of Calcium Consumption
Consumer N
Calcium 76
Non-calcium 2
Camper Supplement Use
33
41
6
10
10
20
30
40
Fre
qu
en
cie
s
Responses
Frequency of Supplements
User N
Supplement 43
Non-supplement 35
Total 78
Results
H01: There is no significant change in knowledge and
understanding of bone health practices.
49%
62%
0%
10%
20%
30%
40%
50%
60%
70%
Pretest Post-test
Perc
en
t C
orr
ect
Knowledge and Understanding Questions
Immediate Knowledge Gained
p<0.0001
H01: There is no significant change in knowledge and
understanding of bone health practices.
49%
65%61%
0
10
20
30
40
50
60
70
Pretest Post-test 21-day Post Test
Perc
en
t C
orr
ect
Knowledge and Understanding Questions
Average Overall Test Score of Campers For Knowledge and Understanding Based
Questions
p<0.0001
H01: There is no significant change in knowledge and understanding of
bone health practices
Test P Value Test Value Confidence
Interval/Effect
Size
Sample Size
Overall Friedman 0.0001 Overall: 48.46 0.4841 Pretest:106
Post-test:107
21-Day Post-
Test: 69
Between
Gender
Mann-
Whitney U
Pretest: 0.35
Post-test: 0.55
Pretest: 1259.00
Post-test:
1337.00
Outside Pretest: 106
Post-test: 107
Between
Locations
Mann-
Whitney U
Pretest: 0.35
Post-test: 0.54
Pretest: 1250.50
Post-test:
1318.50
Outside Pretest: 106
Post-test: 107
Between
Ages
Mann-
Whitney U
Pretest: 0.05
Post-test: 0.01
Pretest: 294.00
Post-test:
251.00
0.4164 Pretest: 73
Post-test: 74
Between
Ethnicities
Kruskal-
Wallis
Pretest: 0.07
Post-test: 0.36
Pretest: 5.29
Post-test: 2.04
Outside Pretest: 73
Post-test: 74
H02: There is no significant difference in
motivation to improve bone health among
campers.
0
10
20
30
40
50
60
70
80
Important Not Important Never ThoughtAbout it
Fre
qu
en
cie
s
Responses
Question 1: It is important for kids my age to have healthy bones
Pretest
Post-test
21-Day Post-Test
(National Osteoporosis Foundation,
2013)
H02: There is no significant difference in motivation to
improve bone health among campers
Test P Value Test
Value
Confidenc
e Interval
Sample Size
Overall Wilcoxon
Signed Ranks
Pretest: 1.00 1.00 Outside Pretest: 78
Post-test: 79
21-day post-test: 60Post-Test: 1.00 1.00
21-Day post-Test: 0.16 0.16
Between
Gender
Mann-
Whitney U
Pretest: 0.90 757.50 Outside Male: 37
Female: 41Post-Test: 0.46 728.58
21-Day Post-Test: 0.49 424.00
Between
Locations
Mann-
Whitney U
Pretest: 0.28 662.50 Outside Elmhurst: 29
West Chicago: 49Post-Test: 0.27 671.00
21-Day Post-Test: 0.42 393.00
Between
Ages
Mann-
Whitney U
Pretest: 0.28 166.50 Outside 5-7 years: 29
8-13 years: 40Post-Test: 0.47 207.00
21-Day Post-Test: 0.43 126.00
Between
Ethnicities
Kruskal-Wallis Pretest: 0.06 5.79 Outside Hispanic: 28
White: 23
Other: 3Post-Test: 0.12 4.20
21-Day Post-Test: 0.15 3.76
H03: There is no significant difference in influence on
food choices among campers.
05
10152025303540
Part
icip
an
ts
Response Average
Influence of Authority Pre-test
05
10152025303540
Part
icip
an
ts
Response Average
Influence of Peers Pre-test
H03: There is no significant difference in Influence of Authority on
food choices among campers.
Test P
Value
Test Value Confidence
Interval/Eff
ect Size
Sample Size
Overall Chi-Square 0.01 Pretest 57.62 0.93 Total: 75
Between
Gender
Mann-Whitney U 0.40 Pretest 1104.00 Outside Male: 45
Female: 54Mean Rank-M 52.50
Mean Rank-F 47.83
Between
Locations
Mann-Whitney U 0.45 Pretest 1112.50 Outside Elmhurst: 45
West Chicago:
54Mean Rank-E 52.28
Mean Rank-W 48.10
Between
Ages
Mann-Whitney U 0.67 Pretest 420.00 Outside 5-7 years: 18
8-13 years: 50Mean Rank-Y 32.83
Mean Rank-O 35.10
Between
Ethnicities
Kruskal-Wallis 0.24 Pretest 2.89 Inside Hispanic: 29
White: 29
Other: 10Mean Rank-H 30.81
Mean Rank-W 35.40
Mean Rank-O 42.60
H03: There is no significant difference in Influence of Peers on
food choices among campers.
Test P
Value
Test Value Confidence
Interval/Eff
ect Size
Sample Size
Overall Chi-Square 0.01 Pretest 31.29 0.92 Total: 80
Between
Gender
Mann-Whitney
U
0.99 Pretest 1146.50 Outside Male: 42
Female: 54Mean Rank-M 48.48
Mean Rank-F 48.52
Between
Locations
Mann-Whitney
U
0.28 Pretest 994.50 Outside Elmhurst: 45
West Chicago:
54Mean Rank-E 45.18
Mean Rank-W 51.08
Between
Ages
Mann-Whitney
U
0.46 Pretest 368.50 Outside 5-7 years: 17
8-13 years: 49Mean Rank-Y 30.68
Mean Rank-O 34.48
Between
Ethnicities
Kruskal-Wallis 0.23 Pretest 2.96 Inside Hispanic: 28
White: 29
Other: 9Mean Rank-H 37.95
Mean Rank-W 30.81
Mean Rank-O 28.33
H04: There is no significant difference in exercise
enjoyment among campers.
0
20
40
60
80
100
120
Yes No I Don't Know
Nu
mb
er
of
Part
icip
an
ts
Participant Response
Pretest Question 18: Exercising is fun
H04: There is no significant difference in exercise
enjoyment among campers.
Test P Value Test Value Confidence
Interval or
Effect Size
Sample Size
Overall Chi-Square <0.001 150.22 .84 108
Between
Genders
Mann-
Whitney U
1.00 1457.50 Outside Male: 53
Female: 55
Between
Locations
Mann-
Whitney U
0.72 1408.00 Outside Elmhurst: 48
West
Chicago: 60
Between
Ages
Mann-
Whitney U
0.75 467.00 Outside 5-7 years: 18
8-13 years:
54
Between
Ethnicities
Mann-
Whitney U
0.71 476.00 Outside Hispanic: 30
White: 32
H04: There is no significant difference in
exercise enjoyment among campers
0
10
20
30
40
50
60
70
80
90
Yes No I Don't Know
Nu
mb
er
of
Part
icip
an
ts
Participant Response
Pretest Question 19: I enjoy exercise
H04: There is no significant difference in exercise
enjoyment among campers.
Test P Value Test Value Confidence
Interval/
Effect Size
Sample Size
Overall Chi-Square <0.001 100.60 .81 109
Between
Genders
Mann-
Whitney U
0.35 1288.00 Outside Male: 52
Female: 54
Between
Locations
Mann-
Whitney U
0.28 1262.00 Outside Elmhurst: 48
West
Chicago: 58
Between
Ages
Mann-
Whitney U
0.19 402.00 Outside 5-7 years: 18
8-13 years:
52
Between
Ethnicities
Mann-
Whitney U
0.63 420.50 Outside Hispanic: 28
White: 32
Participants’ Intent to Participate in
Physical Activities
0
10
20
30
40
50
60
70
80
90
Perc
en
t
Activity
Post-Test
21-Day Post-Test
H05: There is no significant difference in
intent to change bone health practices
among participants
0102030405060708090
100
Nu
mb
er
of
Resp
on
ses
Responses
Question 13: I plan to eat foods that are healthy for my bones
Post-test
Post Post-test
H05: There is no significant difference in intent to change
bone health practices among participants
Test P
Value
Test Value Confidence
Interval
Sample Size
Overall Wilcoxon
Signed Ranks
>0.05 Post-test: 0.90
21-Day post-test: 0.91
Outside Post-test: 109
21-day post-test: 68
Between
Gender
Mann-Whitney
U
>0.05 Post-test: 1410
21-Day Post-Test: 483.5
Outside Male: 84
Female: 93
Between
Locations
Mann-Whitney
U
>0.05 Post-test: 1358
21-Day Post-Test: 466.5
Inside Elmhurst: 60
West Chicago: 107
Between
Ages
Mann-Whitney
U
>0.05 Post-test: 505.5
21-Day Post-Test: 136.5
Outside 5-7 years: 27
8-13 years: 89
Between
Ethnicities
Kruskal-Wallis >0.05 Post-test: 4.88
21-Day Post-Test: 0.35
Outside Hispanic: 57
White: 44
Other: 14
Between
Supplement
Groups
Mann-Whitney
U Test
>0.05 Post-test: 632.5
21-day Post Test: 217.5
Outside Yes: 67
No: 50
Between
dairy
consumers
Mann-Whitney
U Test
>.05 Post-test: 60
21-day Post Test: 18
Outside Yes:114
No: 3
Analysis of 21-day Post-Test Questions
Responses Frequency Chi-
Square
df P-Value
More 39 23.84 2 .0001
Less 5
I don’t know 22
Total 66
0
10
20
30
40
50
More Less I don't know
Nu
mb
er
of
Resp
on
ses
Response
Question 20: Ever since ‘Bone Health Day’ I have done bone healthy activities.
Analysis of 21-day Post-Test Questions
Responses Frequency Chi-
Square
df P-Value
More 39 23.84 2 .0001
Less 8
I don’t know 17
Total 64
0
10
20
30
40
50
More Less I don't know
Nu
mb
er
of
Resp
on
ses
Responses
Question 21: Ever since ‘Bone Health Day’ I have eaten bone healthy foods.
Related Literature
• Harmon et al’s 2014 study
– Built on previous study examining
influence of renovating schoolyards on
physical activity (PA)
– Participants: 4th and 5th graders; N = 393
– Higher ratings of social cognitive theory
variables higher physical activity levels
– Hispanic students had significantly higher
social support scores
• Social environment may determine PA levels
Findings of Circle Questions
Regarding Diet Changes
0
20
40
60
80
100
120
Milk Broccoli Grilledcheese
Tofu Yogurt Mac n'cheese
Nu
mb
er
of
Re
sp
on
ses
Bone Healthy Food Selections
Post-Test Question 17: Circle the foods you plan to eat
Yes
No
Findings of Circle Questions
Regarding Diet Changes
0
10
20
30
40
50
60
70
Milk Broccoli Grilledcheese
Tofu Yogurt Mac n'cheese
Nu
mb
er
of
Resp
on
ses
Bone Healthy Food Selections
21-day Post Test Question 17: Circle the foods you plan to eat
Yes
No
Analysis of Open-Ended Questions
0
2
4
6
8
10
12
14
16
18
Sports Play
Nu
mb
er
of
Resp
on
ses
Responses
21-Day Post-Test Question 20: Give an example of what bone healthy activities you changed
every since Bone Health Day
Analysis of Open-Ended
Questions
0
2
4
6
8
10
12
14
Nu
mb
er
of
Resp
on
ses
Responses
21-Day Post-Test Question 21: Give an example of what bone health foods you changed every since Bone Health Day.
Summary of Results
• Knowledge Outcomes
• Physical Activity
• Perceived Importance
• Influences
– Authority & Peers
• Theories
Strengths, Limitations and Future Applications
Strengths of Batter Up For
Bone Health
• Program is adaptable for gender, ethnicities, SES, ages, cultures, and dietary lifestyles
• Targets lifestyle habits to promote bone health
• Overall low-cost and attention holding for population
• Program saw good retention rates
• Intervention tool was age appropriate for verbiage and utilization of images, pilot test was conducted, color coded for ease of analysis after the intervention
• Mimics bone health practices
Positive Outcomes of Study
• Knowledge
gained
• Knowledge
retention
Limitations of The Study
• Sample size
• Time frame
• Lack of diversity beyond Caucasian and Hispanic
• Reading level of survey too high for younger population
• Tools were not fully validated prior to use
• Time inconsistencies within bases
Future Applications
• Implementation within schools
– Physical education classes
– Science classes
– Health classes
• Can apply to a larger group
• Possible expansion into a longer
program
• Further tool validation
Summary
The Batter Up for Bone Health program is an exemplary theory-based intervention using learner-based activities to promote the importance of bone health during optimal bone development.
Thank you!
• West Chicago School District
• Elmhurst Park District
• Goodie bag donors
• Benedictine University’s Nutrition
Department
• Dr. Karen Plawecki
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