This document summarizes a presentation on robust methods for assessing health-related quality of life (HRQoL). It discusses using quality-adjusted life years (QALYs) to collapse multi-dimensional HRQoL data but notes this can result in biased estimates. A two-step methodology is proposed where HRQoL domains are first estimated separately, then coefficients are transformed to the QALY scale based on predicted values. Simulations show the two-step approach provides less biased estimates than existing single-stage methods. The methodology is applied to SF-6D HRQoL data.
Title:
Adventure Therapy: Treatment Effectiveness and Applications with Australian Youth
Abstract:
This final seminar reviews the original contribution of Bowen’s (2016) PhD thesis to the field of adventure therapy. This thesis advances understanding of the therapeutic uses and treatment effectiveness of adventure therapy by systematically reviewing the efficacy of adventure therapy programs internationally (Study 1), providing an up-to-date profile of Australian outdoor adventure intervention programs for youth (Study 2), examining the efficacy of the Wilderness Adventure Therapy® model of clinical treatment for Australian youth (Study 3), and examining the efficacy of the PCYC Bornhoffen Catalyst program for Australian youth-at-risk (Study 4). Findings from this thesis strongly support the assertion that adventure therapy should be in the suite of therapeutic interventions that operate in diverse service settings across Australia. For more information, see http://www.danielbowen.com.au/research/PhD
Primary supervisor: Assistant Professor James Neill
Supervisory panel member: Professor Anita Mak
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Lutein and Zeaxanthin Supplementation and Association With Visual Function in Age-Related Macular Degeneration
Invest Ophthalmol Vis Sci. 2014 Dec 16;56(1):252-8. doi: 10.1167/iovs.14-15553.
2013 impact factor for Investigative Ophthalmology & Visual Science: 3.661
Propensity Score Methods for Comparative Effectiveness Research with Multiple...Kazuki Yoshida
My dissertation research (and a little more) as presented at the Study Design and Biostatistics Center, Department of Population Health Sciences, University of Utah.
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Title:
Adventure Therapy: Treatment Effectiveness and Applications with Australian Youth
Abstract:
This final seminar reviews the original contribution of Bowen’s (2016) PhD thesis to the field of adventure therapy. This thesis advances understanding of the therapeutic uses and treatment effectiveness of adventure therapy by systematically reviewing the efficacy of adventure therapy programs internationally (Study 1), providing an up-to-date profile of Australian outdoor adventure intervention programs for youth (Study 2), examining the efficacy of the Wilderness Adventure Therapy® model of clinical treatment for Australian youth (Study 3), and examining the efficacy of the PCYC Bornhoffen Catalyst program for Australian youth-at-risk (Study 4). Findings from this thesis strongly support the assertion that adventure therapy should be in the suite of therapeutic interventions that operate in diverse service settings across Australia. For more information, see http://www.danielbowen.com.au/research/PhD
Primary supervisor: Assistant Professor James Neill
Supervisory panel member: Professor Anita Mak
Tea is no longer the gold standard for major abdominal eras casesJeffGadsden
My "con" side of a debate at the Anesthesiology 2019 annual meeting in Orlando, FL against Dr. Ed Mariano (@EMARIANOMD). Some of this is tongue-in-cheek, but the bottom line is that some fascial plane blocks seem to provide equivalent analgesia to thoracic epidurals without the hassle and side-effects, especially hypotension.
Reestenosis, Síndrome coronario agudo. Rol actual de los nuevos antiplaquetarios en el síndrome coronario agudo. Congreso SOLACI Chile 2011.Dr. Ramón Corbalán. Encuentre más presentaciones en la página www.solaci.org/
Lutein and Zeaxanthin Supplementation and Association With Visual Function in Age-Related Macular Degeneration
Invest Ophthalmol Vis Sci. 2014 Dec 16;56(1):252-8. doi: 10.1167/iovs.14-15553.
2013 impact factor for Investigative Ophthalmology & Visual Science: 3.661
Propensity Score Methods for Comparative Effectiveness Research with Multiple...Kazuki Yoshida
My dissertation research (and a little more) as presented at the Study Design and Biostatistics Center, Department of Population Health Sciences, University of Utah.
Association of Anxiety and Depression with Glaucoma-Glaucoma is the third largest cause of blindness worldwide after cataract and trachoma. Along with burden of blindness it also has psychological impact. So this study was designed to find out association of Insomnia, Anxiety and depression with Glaucoma. A case-series type of observational study was carried out on 100 glaucoma cases attended at ESIC Model Hospital, Jaipur (Raj). For assessment of anxiety and depression the Hospital Anxiety and Depression Scale (HADS) and for insomnia modified Diagnostic and Statistical Manual, Fourth edition (DSM-IV) criteria was used. Data collected were analysed and inferred with chi-square test. It was found in this study that Insomnia is associated with Age, Visual acuity in both the eyes and severity of glaucoma in glaucoma cases, with severity of glaucoma it was observed highly significant. Anxiety is associated with Age, Pupilary reaction, Visual acuity in both the eyes and severity of glaucoma in glaucoma cases, with age and severity of glaucoma it was observed highly significant. Depression is not associated with any of supra-said factors in glaucoma cases
The Role of Risk Stratification and Biomarkers in Prevention of CVDCTSI at UCSF
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PUH 5302, Applied Biostatistics 1
Course Learning Outcomes for Unit III
Upon completion of this unit, students should be able to:
4. Recommend solutions to public health problems using biostatistical methods.
4.1 Compute and interpret probability for biostatistical analysis.
4.2 Draw conclusions about public health problems based on biostatistical methods.
5. Analyze public health information to interpret results of biostatistical analysis.
5.1 Analyze literature related to biostatistical analysis in the public health field.
5.2 Prepare an annotated bibliography that explores a topic related to public health issues.
Course/Unit
Learning Outcomes
Learning Activity
4.1
Unit Lesson
Chapter 5
Unit III Problem Solving
4.2
Unit Lesson
Chapter 5
Unit III Problem Solving
5.1
Chapter 5
Unit III Annotated Bibliography
5.2
Chapter 5
Unit III Annotated Bibliography
Reading Assignment
Chapter 5: The Role of Probability
Unit Lesson
Welcome to Unit III. In previous units, we discussed some fundamentals of biostatistics and their application
to solving public health problems. In Unit III, we will compute, interpret, and apply probability, especially in
relation to different populations.
Computing and Interpreting Probabilities
Probability means using a number (or numbers) to demonstrate how likely something is to occur. For
example, if a coin is tossed, the probability of getting a heads or tail is one out of two chances; that is ½.
Researchers have used probability studies to predict weather and other events and have been successful to
some extent. Public health professionals have used statistical methods to predict the chances of health-
related events, thereby providing arguments in favor of taking precautionary measures and warning the
general public on important health issues.
In biostatistics, we use both descriptive statistics and inferential statistics to address public health issues
within a population. In most cases, researchers are not able to study the entire population; they try to get a
sample from the population from which they can generalize their findings.
Descriptive Statistics
Aside from the use of probability sampling methods, there are other methods used for the computation and
interpretation of data; these are generally known as descriptive statistics. With descriptive statistics, we
UNIT III STUDY GUIDE
Probability
PUH 5302, Applied Biostatistics 2
UNIT x STUDY GUIDE
Title
normally compute the mean, mode, median, variance, and standard deviation. Information obtained using
such computation methods is used for descriptive purposes, as opposed to information obtained from
inferential statistics.
Let’s examine this example using the numbers 5, 10, 2, 4, 6, 10, 2, 3, and 2.
The mean is the sum of all the numbers ÷ the number of cases
= 37 ÷ 9
= 4.11
The median is the middle number after the numbers have been arranged in an ascending or descend ...
Title:
A Meta-Analysis of Adventure Therapy Outcomes and Moderators
Abstract:
This presentation reports on a meta-analytic review of 197 studies of adventure therapy participant outcomes (2,908 effect sizes, 206 unique samples). The short-term effect size for adventure therapy was moderate (g = .47) and larger than for alternative (.14) and no treatment (.08) comparison groups. There was little change during the lead-up (.09) and follow-up periods (.03) for adventure therapy, indicating long-term maintenance of the short-term gains. The short-term adventure therapy outcomes were significant for seven out of the eight outcome categories, with the strongest effects for clinical and self-concept measures, and the smallest effects for spirituality/morality. The only significant moderator of outcomes was a positive relationship with participant age.
References:
Bowen, D. J., & Neill, J. T. (2013). A meta-analysis of adventure therapy outcomes and moderators. The Open Psychology Journal, 6, 28-53. doi: 10.2174/1874350120130802001
Bowen, D. J., & Neill, J. T. (2013). A meta-analysis of adventure therapy outcomes and moderators: Pre-post adventure therapy age-based benchmarks for outcome categories. Retrieved from http://www.danielbowen.com.au/meta-analysis
For more information, see: http://www.danielbowen.com.au/meta-analysis
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Robust Methods for Health-related Quality-of-life Assessment
1. Introduction
Methodology
Simulations
Application
Conclusion
Robust Methods for Health-related
Quality-of-life Assessment
Ian McCarthy
Baylor Scott & White Health
Center for Clinical Effectiveness
Utah Health Services Research Conference
April 30, 2014
This project was supported by grant number K99HS022431 from the Agency for Healthcare Research and
Quality. The content is solely the responsibility of the author and does not necessarily represent the official
views of the Agency for Healthcare Research and Quality.
Robust Methods for Health-related Quality-of-life Assessment
2. Introduction
Methodology
Simulations
Application
Conclusion
Background
Cost- and comparative-effectiveness studies becoming
increasingly important
Require assessment of health-related quality-of-life (HRQoL)
outcomes and quality-adjusted life-years (QALYs)
Common approach first collapses the multi-dimensional
HRQoL profile into a one-dimensional QALY (Drummond
et al., 2005; Brazier et al., 2002; Brazier & Ratcliffe, 2007)
EQ-5D
SF-6D
HUI
Robust Methods for Health-related Quality-of-life Assessment
3. Introduction
Methodology
Simulations
Application
Conclusion
Problem
Loss of information when reducing HRQoL profile into QALY, with
potentially biased and inconsistent marginal effects estimates
(Mortimer & Segal, 2008; Devlin et al., 2010; Parkin et al., 2010;
Gutacker et al., 2012):
1 Floor and ceiling effects not present in the underlying domains
but imposed by the scoring algorithm.
2 Nonlinearities in the relationship between the outcome and
independent variables which are difficult to approximate using
the summary score.
Robust Methods for Health-related Quality-of-life Assessment
4. Introduction
Methodology
Simulations
Application
Conclusion
Current Study
1 Monte Carlo study showing the bias of the estimated
coefficients when relying solely on QALYs or some other
summary score based on several ordered outcome variables.
2 Propose new two-step methodology that first estimates
coefficients in each HRQoL domain and then transforms the
coefficients and marginal effects into the QALY domain based
on predicted values from the first-stage regressions.
Robust Methods for Health-related Quality-of-life Assessment
5. Introduction
Methodology
Simulations
Application
Conclusion
Estimating QALYs
Marginal Effects: Standard Approach
Marginal Effects: Proposed Methodology
The SF-6D
Developed by John Brazier and other, the SF-6D is formed from a
subset of questions from the SF-36 or SF-12 and is a common
HRQoL outcome intended to provide a general measure of a
patient’s health status (Brazier et al., 2002; Brazier & Ratcliffe,
2007).
Six dimensions/domains of health: (Physical functioning, role
limitations, social functioning, pain, mental health, and
vitality)
Each domain characterized numerically with a range of
integers. Best value is 1, and worst value ranges from 4 to 6.
Scoring algorithm developed in Brazier et al. (2002) and
Brazier & Ratcliffe (2007) for calculating a population-based
index score from the SF-6D questionnaire
Robust Methods for Health-related Quality-of-life Assessment
6. Introduction
Methodology
Simulations
Application
Conclusion
Estimating QALYs
Marginal Effects: Standard Approach
Marginal Effects: Proposed Methodology
Scoring the SF-6D
Physical Functioning (PF)
PF=2 or PF=3 -0.035
PF=4 -0.044
PF=5 -0.056
PF=6 -0.117
Role Limitations (RL)
RL=2 or RL=3 or RL=4 -0.053
Social Functioning (SF)
SF=2 -0.057
SF=3 -0.059
SF=4 -0.072
SF=5 -0.087
Pain (P)
P=2 or P=3 -0.042
P=4 -0.065
P=5 -0.102
P=6 -0.171
Mental Health (MH)
MH=2 or MH=3 -0.042
MH=4 -0.100
MH=5 -0.118
Vitality (V)
V=2 or V=3 or V=4 -0.071
V=5 -0.092
Combination of Domains
“Most Severe” -0.061
Robust Methods for Health-related Quality-of-life Assessment
7. Introduction
Methodology
Simulations
Application
Conclusion
Estimating QALYs
Marginal Effects: Standard Approach
Marginal Effects: Proposed Methodology
Focus on QALYs
By far the most common methodology for estimating
coefficients and ultimately marginal effects is to first reduce
the multi-dimensional health profile to a one-dimensional
QALY (Austin et al., 2000; Austin, 2002; Richardson &
Manca, 2004; Manca et al., 2005; Basu & Manca, 2012)
Recent literature on how best to accommodate distributional
features somewhat specific to QALYs (Austin, 2002; Basu &
Manca, 2012), including a censored least absolute deviation
model and a Beta MLE approach
Robust Methods for Health-related Quality-of-life Assessment
8. Introduction
Methodology
Simulations
Application
Conclusion
Estimating QALYs
Marginal Effects: Standard Approach
Marginal Effects: Proposed Methodology
First Stage Regression
1 Estimate an ordered probit model separately for each domain,
d = 1, ..., 6, with the follow-up HRQoL response (yid,t1 )
modeled as a function of person-specific variables (xi ),
baseline HRQoL response (yid,t0 ), and treatment status (Ti ).
2 Form predicted probabilities of every possible response, j, in
each domain, d, denoted ˆpd
j .
The regression results provide a predicted (marginal) probability for
each of 31 possible outcomes for each person.
Robust Methods for Health-related Quality-of-life Assessment
9. Introduction
Methodology
Simulations
Application
Conclusion
Estimating QALYs
Marginal Effects: Standard Approach
Marginal Effects: Proposed Methodology
“Most Severe” Category
1 Defined as any one of the following (Brazier et al., 2002): 4
or more in the physical functioning, social functioning, mental
health, or vitality domains; 3 or more in the role limitation
domain; or 5 or more in the pain domain
2 Since the probabilities, Pd
ij , are potentially correlated across
domains, the probability of a “most severe” health status can
be calculated following the principle of inclusion and exclusion
for probability:
P (A1 ∪ A2 ∪ ... ∪ AN) = P (A1) + ... + P (AN) +
N
n=2
(−1)n+1
P (∩ n events) .
Robust Methods for Health-related Quality-of-life Assessment
11. Introduction
Methodology
Simulations
Application
Conclusion
Marginal Effects on QALYs
Treatment Effects with Selection
Data Generating Processes
The D × 1 vector of latent HRQoL values, y∗
i , is simulated as
follows:
y∗
i = γ + βxi + εi , where
ε ∼ N (0D×1, ID×D) ,
x ∼ U[0, 1],
γ = ID×1, and
β = 1.5 × ID×1.
Discrete HRQoL values are generated based on the value of the
latent value, y∗
id , relative to the Jd × 1 vector of threshold values in
each domain.
Robust Methods for Health-related Quality-of-life Assessment
12. Introduction
Methodology
Simulations
Application
Conclusion
Marginal Effects on QALYs
Treatment Effects with Selection
Simulated QALY Distributions
01020304050
Frequency
.4 .6 .8 1
SF-6D Index Score
010203040
Frequency
.2 .4 .6 .8 1
SF-6D Index Score
01020304050
Frequency
.4 .6 .8 1
SF-6D Index Score
020406080
Frequency
.3 .4 .5 .6 .7 .8
SF-6D Index Score
050100150200
Frequency
.4 .6 .8 1
SF-6D Index Score
Robust Methods for Health-related Quality-of-life Assessment
18. Introduction
Methodology
Simulations
Application
Conclusion
Data Summary
Results
Data
Data collected prospectively on adult scoliosis patients from over
10 participating members of the International Spine Study Group
(ISSG).
Variable Mean Standard
Deviation
Age 56.76 14.51
BMI 26.59 5.84
Baseline SF-6D 0.61 0.12
Follow-up SF-6D 0.66 0.12
Count Percent
Operative 193 53%
Female 309 85%
Robust Methods for Health-related Quality-of-life Assessment
22. Introduction
Methodology
Simulations
Application
Conclusion
Intuition
Collapsing multi-dimensional profile into a single summary
measure introduces floor/ceiling effects and nonlinearities that
are difficult to accommodate in a single equation framework.
With selection into treatment (whether on observables or
unobservables), standard methods relying only on QALYs
provide biased estimates of true treatment effect.
An alternative approach is to estimate coefficients based on
the full health profile and then re-interpret effects in the
QALY domain based on predicted probabilities in the
first-stage regressions.
Robust Methods for Health-related Quality-of-life Assessment
24. Introduction
Methodology
Simulations
Application
Conclusion
Bibliography I
Austin, P.C. 2002. A comparison of methods for analyzing health-related quality-of-life measures. Value in Health,
5(4), 329–337.
Austin, P.C., Escobar, M., & Kopec, J.A. 2000. The use of the Tobit model for analyzing measures of health
status. Quality of Life Research, 9(8), 901–910.
Basu, A., & Manca, A. 2012. Regression Estimators for Generic Health-Related Quality of Life and
Quality-Adjusted Life Years. Medical Decision Making, 32(1), 56–69.
Brazier, J., & Ratcliffe, J. 2007. Measuring and valuing health benefits for economic evaluation. Oxford University
Press, USA.
Brazier, J., Roberts, J., & Deverill, M. 2002. The estimation of a preference-based measure of health from the
SF-36. Journal of health economics, 21(2), 271–292.
Devlin, N.J., Parkin, D., & Browne, J. 2010. Patient-reported outcome measures in the NHS: new methods for
analysing and reporting EQ-5D data. Health economics, 19(8), 886–905.
Drummond, M.F., Sculpher, M.J., & Torrance, G.W. 2005. Methods for the economic evaluation of health care
programmes. Oxford University Press, USA.
Gutacker, N., Bojke, C., Daidone, S., Devlin, N., & Street, A. 2012. Analysing Hospital Variation in Health
Outcome at the Level of EQ-5D Dimensions.
Manca, A., Hawkins, N., & Sculpher, M.J. 2005. Estimating mean QALYs in trial-based cost-effectiveness analysis:
the importance of controlling for baseline utility. Health economics, 14(5), 487–496.
Mortimer, D., & Segal, L. 2008. Comparing the incomparable? A systematic review of competing techniques for
converting descriptive measures of health status into QALY-weights. Medical decision making, 28(1), 66.
Parkin, D., Rice, N., & Devlin, N. 2010. Statistical analysis of EQ-5D profiles: does the use of value sets bias
inference? Medical Decision Making, 30(5), 556–565.
Richardson, G., & Manca, A. 2004. Calculation of quality adjusted life years in the published literature: a review of
methodology and transparency. Health economics, 13(12), 1203–1210.
Robust Methods for Health-related Quality-of-life Assessment