SURVEYS Flashcards
NHANES
National Health and Nutrition Examination Survey => All 5 areas of Nutritional Assessment NHANES I, II, III – 1970s-1990s - One 24 h recall only- back then people didnt know that this wasnt good enough- they then began doing 2 recalls
participants are “randonly” seleted and have to go complete a survey
Ongoing NHANES: yearly since 1999-00
what does NHANES use.
what do they do
uses mobile examination
centers (MEC)
MEC consist of four large trailers with the
diagnostic equipment to conduct a wide range of
physical and biochemical evaluations.
Physical examination = body measurements, a
variety of X-rays, audiometry, electrocardiography,
bone densitometry, allergy testing, and spirometry
(lung).
Dental examination.
Specimen collection (blood and urinary analysis).
Personal interview for nutrition-related information;
data on tobacco use among youngsters, sexual
experience, and depression; and tests of cognitive
development and learning achievement.
what do otehr countries use
NHANES-like surveys are becoming more and moe popular
what does Canada do
1970-72 = Nutrition Canada
Nutritional Assessment
Some biochemical measures (few available in
1970s)
Dietary assessment only a single 24h recall
Measured Ht and Wt but not BMI (wasnt really around then)
1990s = provincial nutrition surveys
diet was adjusted intake to “usual”
measured ht and wt
Only adults
Food Disappearance: CCHS Guide page 74
per capita food availability (purchased) yearly (look at food disapearances- cant see whos buying it though, or to see if the food was consumed- thrown away, fed to dog)
Canadian nutrition survey techiniques
24-h recall, ffq
repeated 24-h recall, ffq
do everyting as possible to not do follow-up- do it then
CCHS 2-year Cycle Design
Year 1 – “General” 130,000 respondents Stratified by health region Content common optional sub-sample Estimates for health regions, provinces, territories, Canada Called 1.x
Year 2 – “Focus” 30,000 respondents Stratified by province Content focus (60+ minutes) correlates Estimates for provinces, Canada (excluding territories) Called 2.x
CCHS Cycle 2.2: 2004
Focus = Nutrition
Sample 35,000 (oversmapled)
population aged 0+
national (excluding territories) & provincial
Residents of private households
Exclusions:
Indian reserves / crown lands
institutions (health institutions, prisons, religious
institutions, convents, etc.)
members of Canadian Forces
certain remote areas (north of Ontario and Québec)
Coverage (general) ~98% of targeted population
CCHS 2004 – Objectives – Intake
Estimates of usual dietary intake
“Usual” to be explained later – but allows for
comparison to DRIs
Measurement of foods (therefore nutrients), food
groups, dietary supplements & eating patterns
- Distribution of usual dietary intake at provincial and
national levels for all of the 15 DRI age/sex groups
Measures of the prevalence of household food
insecurity, scored using answers to series of
questions
would measure during a 24 hour period- would take data on where you ate and what you were eating
CCHS 2004 – Objectives – Anthropometry and
Activity
Estimates of Anthropometric measurements self-reported & measured height & weight Adiposity Collect correlate information physical / sedentary activity selected health conditions socio-demographic characteristics
CCHS Sample Design
Interview mode
1st interview (24-hour recall & general health) face-toface
2nd interview (24-hour recall) telephone (only chose 30% of the sample because of time and cost)
Proxy protocols
Respondents aged 12+: non-proxy (away from caregiver)
Aged 6 to 11: assisted-proxy (respondent and parent)
Aged 0 to 5: proxy (parent)
Computer-assisted interviews:
customized questionnaires, automated edits
General health component collect correlates & socio-demographics selected health conditions physical / sedentary activity household food security vitamin & mineral supplements ht & wt (self-reported, measured) 24-hour dietary recall component all foods & beverages during 24-hour
General Health Component
General Health (12y+) Physical Activity (12y+) Physical Activity (6-11y) Sedentary Activity (12 – 17y) Measured Ht, Wt (2y+) Self Reported Ht, Wt (10% sample, 18y+) Vitamin and Mineral Supplements (all ages) Household Food Security (all ages) Fruit and Vegetable Consumption (6 mo.+) Women’s Health (9y+) Chronic Conditions (all) Smoking (12y+) Alcohol Use (12y+) Socio-Demographics (all ages) Labour Force (15-75y) Income (all ages)
24-Hour Recall-AMPM
(all surveyors are using the same system
Food and drink from Midnight to Midnight
USDA’s automated multiple pass methodology
application (AMPM) five steps :
quick list – quick report
collect list of foods & beverages consumed
forgotten foods – anything else with that?
probes for foods forgotten in quick list
time and occasion – when / group items
collect time & eating occasion for each food
detail cycle – details
for each food, collect detailed description, amount &
additions
food booklet
final probe – any other food / beverage ?
2015 CCHS Nutrition Survey
Successfully completed Jan-Dec 2015 Similar design Many wanted North (Nunavit etc.) = too costly No one under 1 y of age Data are ready – some challenges compared to 2004 We will be able to compare to 2004 for most measures
What has been published?
Intakes of all major macro-and micronutrients;
from food and supplements
Beverages, sugar, salt, ultra-processed
foods, pulses
Food insecurity
Diet quality, Healthy eating Intake (HEI)
BMI
Canadian Health Measures Survey (CHMS)
adds the biological
Is an ongoing survey - does not have in-depth nutrition Wanted a Canadian survey similar to NHANES Survey started in 2007 using one mobile clinic. Now there are 2. - All 4 seasons; across Canada – chosen to be representative of Canada as a whole, not regionally
is done every 2 years and does not have a 24 hour recall. not geographical- trying to hit most densely populated
CHMS-Overview
Each 2-year cycle is ~ 5500 people - Cycle 1 = age 6 to 79 y - Cycle 2 and beyond = 3 to 79 y ~ At 15+ centres across Canada, recruiting 500 to get > 300 subjects each First published results: March 2010
(they go to a center , for example red deer, and go out and collect date in a 100 km radius to get rural people already)
Measures of Importance for
Nutrition/Disease
Measured height and weight Blood Pressure, fasting glucose, blood lipids Hemoglobin, Hct, MCV, ferritin in CBC Kidney function, including blood urea Muscular strength – including grip Oral health (just Cycle 1) Several food questions – frequency of use Milk/ fish/ soft drinks/some veg
health survey- not just nutrition
What are nutrition-related measures?
Plasma (now serum) 25(OH)D Red blood cell folate Serum vitamin B12 Also plasma homocysteine Urinary iodine (I/Cr ratio) Investigator initiated measures
What are nutrition-related measures?
Plasma (now serum) 25(OH)D Red blood cell folate Serum vitamin B12 Also plasma homocysteine Urinary iodine (I/Cr ratio) Investigator initiated measures
New for Cycles 3 and 4
Skin Pigmentation (in cycles 1 and 2 they asked about outdoor time but not sunscreen so they now easure skin pigmentation)
• Quantify the association/correlation between natural
skin pigmentation and Vitamin D status among the
Canadian population;
• Assess relationship between skin pigmentation and
degree of sun exposure with skin cancer;
• Policy development on issues relating to natural skin
pigmentation and sun exposure (tanning); and
• Develop sun safety recommendations
Spectrophotometric measure of skin pigmentation:
Measures are taken in triplicate of the upper inner arm
(unexposed skin) and outer forearm (exposed skin).
Provides measure of natural skin pigmentation and
relative quantification of recent sun exposure (tanning).
Cycles 5,6 and 7,8
we arenow in cycle 6
researchers are feeling fatigued for every 2 years
Treat cycles 1-4 as one unit: total 20,000
1 = 2007-09; 2 = 2009-2011
3 = 2012&2013; 4 = 2014&2015
Treat cycles 5-8 as complete block with
similar measures
Cycle 5= 2016-17
Some measures cycled in/out to keep time
in clinic same
Treat cycles 1-4 as one unit: total 20,000
1 = 2007-09; 2 = 2009-2011
3 = 2012&2013; 4 = 2014&2015
Treat cycles 5-8 as complete block with
similar measures
Cycle 5= 2016-17
Some measures cycled in/out to keep time
in clinic same
Vitamin D (25OHD) Vitamin C (serum ascorbic) Folate (and homocysteine) B12 (and homocysteine) Iron status Metabolic Syndrome Omega 3 fatty acids BMI
Dietary Assessment of Groups
advantages and disadvantages
Advantages;
24 h recall is usual intake of groups but needs
to be “adjusted”
FFQs are fat if coded electronically = usual
intakes
Challenges:
Methods requiring multiple visits such as
diaries are very expensive
Bias as those with poor diets do not
participate
