From a research question to study objectives. Key areas Levels in fundamental or applied research...
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Transcript of From a research question to study objectives. Key areas Levels in fundamental or applied research...
From a research question to study objectives
Key areas
• Levels in fundamental or applied research
• Working with policymakers to understand their data needs
Asking yourself the right question
• Two ways to deal with a poor or irrelevant research question:– Try to answer it
• The answer may be of no use of anyone• There may be no answer…
– Try to reframe it
• If your research question is wrong: – No matter how much effort you put in your
study, it will be irrelevant…
• If your research question is right:– You have an opportunity to do a good job
Fundamental and applied epidemiological projects
Type of projects Objective of the investigations
Relevance to field epidemiology
Fundamental researchTheoretical rationale
-
Applied research Efficacy +
Prevention research Effectiveness ++
Assessment, monitoring and evaluation
Implementation +++
Progressing towards applied research questions: Immunization
example• Fundamental research
– Studies assessing candidate vaccine antigens
• Applied investigation– Clinical trials
• Prevention research– Social marketing, cost effectiveness
• Assessment, monitoring and evaluation– Post implementation evaluation,
coverage survey
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify information needed for decision making/policy change
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify the information needed to improve
Identification of a public health problem
• Any disease, injury, risk factor, environment threat or social condition that can cause death / disability
• Points that need to be characterized– What
• Nature / etiology of the condition– How much
• Magnitude– Who
• Population at risk – Where
• Geographic locations– When
• Time of occurrence / seasonal variations
Health problem statement: Example
• Pertussis rates in Poland, increased from 0.8 to 8 per 100,000 between 1993 and 2004, particularly affecting adolescents and adults, which maintain circulation
• Specifies:– What– Where – How much– When – Who
Pertussis cases per 100,000 inhabitants by year, 1985-2009,
Poland
0
2
4
6
8
10
1985 1990 1995 2000 2005
Year
Noti
fica
tions
/ 100,0
00
Source: NIPH, Poland
Pertussis cases, by age group, 1985-2008, Poland
0 %
20 %
40 %
60 %
80 %
100 %
1985 1989 1993 1997 2001 2005
Year
Pro
port
ion o
f noti
fied c
ase
s
0-4 5-9 10-14 >15 Source: NIPH, Poland
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify the information needed to improve
Criteria used to assess the public health importance of a problem
• Burden of disease– Use local, national and international estimates
• Death
• Disease
• Disability
• Economic losses
• Recent emergence
• Availability of effective interventions
• Cost effectiveness of interventions
Public health importance of pertussis in Poland
• Burden– Pertussis in unvaccinated infants can be fatal
– Untreated pertussis in adults: loss of productivity
– Estimated 300,000 deaths worldwide (13 million DALYs/year)
• Possible interventions– Targeted antibiotic decreases complications
– Vaccination: immunity ~ 10 years• Recommended “cocoon strategy”
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify the information needed to improve
Analysing a public health problem:Spreading out issues to identify
options
• Identify the problem– E.g., High pertussis rates– Increase of disease transmission among adults
• Identify causes – Immediate determinants
• E.g., Waning immunity• Surveillance bias
– Direct and indirect contributing factors• E.g., Changes in pertussis strains
• Identify consequences– E.g., Increased risk for unvaccinated infants
• Identify possible solutions– E.g., Implement booster doses in adults– Identify candidate strains for vaccine
1 1Health
problem
Determinants
Direct contributing
factors
Indirect contributing
factors
Consequences: -1 -2 -3
2
3
2
<Specify>
<Specify>
<Specify>
Determinants and contribution factors diagram for a public health
problem
Possible intervention 1
Possible intervention 2
Possible intervention 3
Pertussis
Exposure
Health problem
Determinants
Direct contributing
factors
Identifi-cation ofcandidate
strains
Treatment
Ineffectivevaccine?
(coverage 95%)
HCWs
Teachers /Police
An analysis of the problem:Pertussis in Poland
Immuni-zation
boosterdoses
travel
Strainreplacement
Young children:- death- disability
Adults:- Loss of productivity
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify the information needed to improve
Reviewing planned, ongoing or completed interventions
• Locate the level of the various interventions:– Determinants– Contributing factors
• Review effectiveness• Estimate cost effectiveness• Analyze implementation status
– Input – Process – Outcome
Interventions for pertussis in Poland
• Treatment of cases– Antibiotics and supportive treatment
• Immunization– Intervention
• 3 doses of primary vaccination• 2 boosters during the 2nd and 6th year
– Implementation• Reported coverage: 95%• No validation• No monitoring of high-risk groups
Data needs assessment
• Identify public health problems
• Estimate public health importance
• Analyze problems
• Review what is being already done
• Identify the information needed to improve
Identifying the information needed to allow better prevention and
control
• Is the problem a consequence of a failure to implement a well validated strategy?– Need of assessment, monitoring and evaluation
• Is the problem a consequence of difficulty to apply a recommended strategy?– Need of prevention research
• Is the problem a consequence of a limitation or of a lack of validated strategy (i.e., the recommendations are implemented but they don’t work)?– Applied investigation
Making sure you are not re-inventing the wheel
• Identify what is known (easy)– Guidelines
– Recommendations
– Reviews
– Literature search
• Identify what is not known (difficult)– Meeting reports
– Research agenda
– Expert opinion
What is known and unknown about pertussis in Poland
• Established facts– Primary immunization protects small children– Boosters are needed for limiting transmission– Reported vaccine coverage is high– Seroprevalence indicate high circulation
among adults
• Areas of uncertainty:– Vaccine failure?
• Is the vaccine as effective as it is supposed to be ?
– Role of particular adult groups in infant exposure
• Evidence needed for vaccination of adults
Prevalence of anti-Ptx IgG antibodies in the Netherlands,
2006-2007
Source: de Greeff SC, et al. PLoS One. 2010 Dec 1;5(12):e14183.
Anticipating what will be done with the information that will be delivered by an applied
research project
• Anticipate the various possible results of the study– Imagine scenarios of various possible
answers to the research question
• Identify the kind of public health action that could be realistically taken for each case scenario
Framing the research question
To provide evidence for possible introduction of booster pertussis vaccination among adults (prioritize either universal adult vaccination or cocoon strategy).
Objectives of the study
• To measure incidence of pertussis among adults with prolonged cough
• To compare obtained estimates with notification rates
Expected benefit of pertussis study in Poland
• If the study will identify adult groups with high burden of pertussis– Evidence for strenghtening “cocoon” strategy
– Evidence for recommending booster vaccination in adults
• Potential validation of surveillance figures
• Possible next question– What is the best strategy to use to increase
the coverage of booster among adults?
Evolving public health concepts are like onions being peeled
• Sound answers to good research question allow prevention BUT bring new questions
• These questions should be framed with the same careful methods
• Addressing consecutive publichealth questions is:– Useful
– Gratifying
The life cycle of epidemiological investigations: The never ending
storyIdentifying data needs
Spelling out the research question
Formulating the study objectives
Planning the analysis
Preparing data collection instruments
Analysing data
Drawing conclusions
Formulating recommendations
Involving the programme
Collecting data
Here we go again
Take home messages
• Work with public health managers– to understand the public health problem
– to apply your results immediately
• Imagine yourself with your results in hands– Imagine how they would contribute to better
health
– Determine how the results will guide new prevention / control opportunities