Demography of Diabetes

8/8/2019 Demography of Diabetes

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Demography of Diabetes

Stanley Ellicott

Yusuke Kato

Mark Reinardy

Katherine Short

DATA PRESENTATION | DEC 7, 2010


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Why Diabetes? Diabetes is a metabolic disease: type I/II and gestational forms

23.6 million US adults and children have diabetes

Diabetes is the 7th leading cause of death (2006)

Diabetes cost $174 billion in 2007: $116 billion for direct medical

costs, and $58 billion for indirect costs (disability, loss of work,premature mortality)

The most common form of diabetes, type II, is almost entirelypreventable through diet and exercise

Source: American Diabetes Association, http://www.diabetes.org/diabetes-basics/diabetes-statistics


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Research Questions1: Are diabetes and level of income/food stamp participationindependent?

2: Is the frequency of diabetes equal across differing levels ofeducational attainment?

3: Is there a diff

erence between regions with low/high rates ofexercise with respect to diabetes prevalence?


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Data Sources

Data are from the 2007 California Health Interview Survey

51,048 survey participants

453 variables, including:

Respondents affirmed I have been told by a doctor I have

diabetes, and did not disambiguate Type I/II

Household income

Educational attainment

Data are Population-based random-digit dial telephone surveyof Californias population conducted every other year since 2001

Data gatherers actively sought to fight response bias

Education and Food Security


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Data Sources, cont.

National diabetes prevalence rates are from the National Centerfor Chronic Disease Prevention & Health Promotion, BehavioralRisk Factor Surveillance System (2006)

Respondents affirmed I have been told by a doctor I havediabetes, and did not disambiguate Type I/II

Exercise rates are from the Department of Labor, Bureau of LaborStatistics, American Time Use Survey (2003-2006)

Rates are averages from individuals aged 15 and older, by region,over the 2003-2006 period

Regions were grouped by exercise rate, and rates are percent ofpeople aged 15 and older who engaged in exercise on an averageday, by region, 2003-2006 period

Exercise


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Test 1: Summary Statistics


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Test 1: Food SecurityHYPOTHESIS:

STATISTICAL TEST:

RESULTS:

EFFECT SIZE:

INTERPRETATION:

Incidence of diabetes and qualifying for food stampbenefits are independent

Chi-Square test for independence

X2

= 320.52 (DF: 1)

Phi = .08

With p


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Test 1: Food Security, cont.Two related tests:

1: One-tailed T-test for proportions of those who qualify/do notqualify for food stamps with diabetes

Hypothesize proportions are equal

People qualifying for FS with diabetes: 14.23% + 0.5% People not qualifying for FS with diabetes: 9.13% + 0.3%

Z=17.90

Thus, we conclude there is a significant, positive correlation

between qualifying for food stamps and being diagnosed withdiabetes/pre-diabetes (p


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2: Chi-Square Test for Independence between two food stampclassifications: qualified claimers, qualified non-claimers andstatus of diabetes: diabetic and pre-diabetic

Hypothesize independence between categories X

2 = 4.7704 (DF: 1), P=.029

Effect Size: Phi = .01

We have sufficient evidence to conclude receiving foodstamps is not independent of diabetes or pre-diabetes (p


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2A: Two-Sample Test of Proportions to determine the significanceand direction of the difference

Hypothesize independence between categories

Z=2.184We have sufficient evidence to conclude that among those whoqualify for food stamps, there is a negative relationship betweenreceiving food stamps and being diagnosed with diabetes/pre-diabetes (p


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Test 2: EducationHYPOTHESIS:

STATISTICAL TEST:

RESULTS:

EFFECT SIZE:

INTERPRETATION:

Frequency of diabetes cases within levels ofeducation are equal

Chi-Square test for goodness of fit

X2

= 1,303.15 (DF: 6)

.1599

At p


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Test 3: Summary Statistics Area with a low exercise level (yellow & orange), proportion ofpeople who were told to have diabetes=.089, Sample size=100,589

Area with a high exercise level(blue & dark blue), proportion ofpeople who were told to have diabetes=.074, Sample size=128,407


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Test 3: ExerciseHYPOTHESIS:

STATISTICAL TEST:

RESULTS:

INTERPRETATION:

P(diabetes rate in area of low exercise level) P(diabetes rate in area of high exercise level)

1 Tailed Z test

Z = 12.96, p


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Policy Recommendations Increased efforts to enroll qualified participants in food stampprograms would play an important role in fighting diabetesamong lower income brackets

Given the disproportionate variability of incidents of diabetesamong groups with lower levels of education attainment, it mightargue for a seminar or program in high schools to inform studentsof healthy eating and lifestyle habits

Restore funding to physical education programs in publicschools to encourage development of healthy exercise habits


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Thank you!

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Demography of Diabetes