Hierarchy of Evidence
- as we go up quality of evidence gets better (more confident)
- Risk of bias gets lower as you go from top to bottom
Meta-analyses and systematic reviews
RCT (randomized control trials but not really in growth trials, ex: cant put someone on diet)
Prospective cohort
Retrospective cohort
Case- control study
Cross sectional study
Case series
Expert opintion
- 3 studies we will talk about, as you go up on list….
Case Study
- Repeated measures on a _____ ____ over time
Strengths:
* Easy to _____, low _____
* Represents __________ growth pattern
Weaknesses:
* Not representative of ______________
- Strong individual biases: (3)
* No understanding of variability ______ _____
- Longitudinal or Mixed Longitudinal Study (prospective cohort)
- Cross-sectional Study
- Case Study of Individual
- Validity/Accuracy of Growth increases
- Repeated measures on a single person over time
Strengths:
* Easy to organize, low cost
* Represents individual growth pattern
Weaknesses:
* Not representative of population
* Genetics, environment, SES
* No understanding of variability between people
Cross-Sectional Design: Growth Study Application
* Each person measured ____
* Different people/cohorts at each ____
* _____ measure; single or multiple cohorts
- ___, _____, and relatively accurate snapshot of what patterns might be like
Cross-Sectional Design: Strengths and Limitations.
Strengths:
* Sim….
* Che…
* Good r______
* No ______ effect
* Shorter….
Weaknesses:
* Sampling bias: are only what type people volunteering for study?
* Cohort bias: different exposure of….
- May not accurately represent the dynamics of growth: Average age group values with mixed maturity levels may ____ amplitude of ____
- Each person measured once
- Different people/cohorts at each age (kids born at different times)
- Single measure; single or multiple cohorts (at every single measure, different people)
- Fast, cheap, and relatively accurate snapshot of what patterns might be like
Cross-Sectional Design: Strengths and Limitations.
Strengths:
* Simple
* Cheap
* Good retention – participants and staff (low drop out)
* No learning effect
* Shorter collection period!
Weaknesses:
* Sampling bias: are only fit/active individuals volunteering for fitness studies
* Cohort bias: Different exposure of some age groups to important biasing factors such as nutrition (COVID)
- May not accurately represent the dynamics of growth: Average age group values with mixed maturity levels may blunt amplitude of growth
Cross sectional vs. Longitudinal Measurement of Growth (maturity = puberty)
* Cross -sectional measurements may misrepresent the true ______ and _____ of growth curves, especially during pubertal years
- Less _______ growth spurt (magnitude)
- ________ growth spurt (duration)
- Growth records of an individual will not exactly match _____ _____ on growth charts
X-sectional vs. Longitudinal Measurement of Growth (maturity = puberty)
* X-sectional measurements may misrepresent the true shape and magnitude of growth curves, especially during pubertal years
- Less intense growth spurt
- Longer growth spurt
- Growth records of an individual will not exactly match centile lines on growth charts
Simple Longitudinal Study Design
* Often conducted ______ a cross-sectional study
* Cohort (born at same time) and…..
- Repeated measures of _____ individual at ____ times and ages
- What kind of groups
- All groups have same what two things
- Often conducted after a cross-sectional study
- Cohort (born at same time) and followed over time
- Repeated measures of same individual at different times and ages
- Single or multiple groups
- All groups have same starting and ending age
Longitudinal vs. Cross-sectional Study
Strengths of longitudinal:
* Better represents ____ variability
* Better represents _____ dynamics
Weaknesses of longitudinal:
* Poorer retention, meaning….
* L_____ effects
* M_______ effects
* Longer data collection, therefore….
Strengths of longitudinal:
* Better represents population variability
* Better represents growth dynamics
Weaknesses of longitudinal:
* Poorer retention (greater drop-out)
* Learning effects
* Motivational effects
* Longer data collection (costly)
Mixed Longitudinal Design
* ______ cohorts
* Repeated measurements at different _____
* Same individuals for part of…..
* Different starting and ending ____/____
* Typically, same starting time for…
- example of this
Mixed Longitudinal Design
* Multiple cohorts
* Repeated measurements at different times (different ages)
* Same individuals for part of the period
* Different starting and ending ages/cohort (captures 8-16 in 4 years instead of 8)
* Typically, same starting time for all cohorts
- UBC Healthy Bones Study
Mixed Longitudinal Designs
* Covers a ____ age range in ____ time vs. simple longitudinal study
* Fewer problems with what 4 things vs. simple longitudinal study
- Not truly representative of the entire period of ______ growth of a particular cohort, but pretty good _____!
- Covers a broad age range in less time vs. simple longitudinal study
- Fewer problems with recruitment, retention, learning and motivation vs. simple longitudinal study
- Not truly representative of the entire period of longitudinal growth of a particular cohort, but pretty good approximation!
How do we Measure Somatic Growth?
- During ____-____ development
Post-Natal Assessment Techniques (Somatic Growth)
* Describe the _____ ____ parameters that change over time
* Need _____ ways to measures these!
- During post-natal development
- Describe the physical growth parameters that change over time
- Need accurate ways to measures these!
Tools for Measuring Post-Natal Somatic Growth
- Vertical Stadiometer , what measure
- Horizontal Stadiometer, what measure
- Mass scale , what measure
- Anthropometer , what measure
- Tape measure, what measure
- Calipers, what measure
Standing Stature
- what age is this done at
- Diurnal variation: ____ during day
- The _____ Plane
- Vertical Stadiometer (Standing Stature)
- Horizontal Stadiometer (Recumbent Stature)
- Mass scale, weight
- Anthropometer (breadths/width)
- Tape measure (girths/circumferences)
- Calipers (skinfold thickness)
- 2 years +
- Diurnal variation: decreases during day
- The Frankfort Plane
Recumbent Length (Lying Stature)
* Birth until child can ____ , what age
* Usually slightly larger than ______ ____
Components of Stature
Trunk height = _____ height
* Distance from top of head in…..
* Crown to rump length in what age
Leg length = _____ height
= standing stature – ____ height
- Ratio of trunk to leg length is a measure of ____
Recumbent Length (Lying Stature)
* Birth until child can stand (0 to 2 years)
* Usually slightly larger than standing stature
Trunk height = sitting height
* Distance from top of head in a seated position
* Crown to rump length in <2 years
Leg length = subischial height
= standing stature – sitting height
- Ratio of trunk to leg length is a measure of proportionality
Anthropometer
- Shoulder/hip ratio = bi-_____ / bi-____ ratio
- Bi-Acromial Diameter: across _____ process
- Bi-Cristal Diameter: across ______ crests
- Anthropometric tape what is
Body Mass
* Light ______
* Diurnal variation: ____ during day
- Shoulder/hip ratio = bi-acromial / bi-cristal ratio
- Bi-Acromial Diameter: across acromial process
- Bi-Cristal (iliac) Diameter: across iliac crests
- measuring tape, can be used to measure brain growth in kids
Body Mass
* Light clothing
* Diurnal variation: increases during day
Summary of Post-Natal Somatic Assessment
* Standard anthropometric techniques used to assess gross ______ features
* Not the separate ______ compartments comprising the body.
- Each has specific methodology/practical standards that require ____ ____
- Used mostly in _____ clinical assessments or in ____ scale health-related studies
- Replaced with more sophisticated techniques when the purpose is to investigate growth of _____ tissue _____ of the body – mostly used in research or diagnosis of pathology
- Standard anthropometric techniques used to assess gross somatic (physical) features
- Not the separate tissue compartments comprising the body.
- Each has specific methodology and practical standards that require specialized
training (CSEP Exercise Physiologist, Personal Trainer). - Used mostly in individual clinical assessments or in large scale health-related studies
- Replaced with more sophisticated techniques when the purpose is to investigate growth of specific tissue compartments of the body – mostly used in research or diagnosis of pathology
Dual X-Ray Absorptiometry (DXA) use - DXA Measures
- Bone _____ ______ (aka bone ‘mass’) in grams
- L_____ mass (grams)
- F___ mass (grams)
- Bone mass + lean mass + fat mass = ?
Original Use
* Diagnosis of _______, in older women
* Measures are related to risk of _____ fracture
- Bone mineral content (aka bone ‘mass’) in grams
- Lean mass (grams)
- Fat mass (grams)
- Total body mass
- Diagnosis of osteoporosis, in older women
- Measures are related to risk of osteoporotic fracture
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Intro to Growth32
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Study design14
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Growth charts part 110
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Growth charts part 224
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Post natal growth (after midterm)27
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Weight-neutral approaches to health (Guest lecture)1
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Prenatal part 122
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Prenatal part 226
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Prenatal part 315
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Sex Determination11
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Endocrine23
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Biological Maturation35
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Skeletal System30
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Growth Injuries13
