Using randomised control trials to evaluate public policy * DIISRTE

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Using randomised control trials to evaluate
public policy – Presentation to
DIISRTE/DEEWR workshop, January 31
Jeff Borland
Department of Economics
University of Melbourne
1. Outline
• Why do RCTs?
• Case studies of RCTs I am involved with (jointly
with Yi-Ping Tseng at the Melbourne Institute)
• Criteria for determining feasibility and value
• Designing and conducting an RCT
2. Why do RCTs?
• A sure way to solve the ‘evaluation problem’:
Can create a control group that can be regarded
as identical to the treatment group except being
affected by the policy intervention.
• Flexibility: Can test exactly the policy you want
to evaluate. Can test a ‘whole’ policy, or its
component parts. Can test the effect of a policy,
or the causal mechanism that is believed to
underlie behind the effect of the policy.
3. Case study 1: YP4 – Case management
for young homeless jobseekers
a. Main features:
• Intervention: Assignment of a case manager to
help tailor and coordinate available services to
reflect the specific circumstances of young
homeless jobseekers – for 18 to 30 months.
• Partners: Project undertaken at initiative of and
managed by Hanover Welfare and 3 other not-forprofit partners, each responsible for a geographic
location (Cheltenham, Frankston, Bendigo and
Inner Melbourne).
• Eligibility: Required to be aged 18 to 35 years,
in receipt of Newstart Allowance or Youth
Allowance (other), homeless or with a history of
homelessness, and ‘disadvantaged’, as
evidenced by eligibility for the Personal Support
Program (PSP), Job Placement, Employment and
Training (JPET) program or Intensive SupportCustomised Assistance (ISCA).
• Timing: Recruitment took place over the period
January to December 2005, all case
management services ceased in June 2007, and
final data collection was completed in early 2009.
• Size of trial: Target of 240 treatment and 280
control participants – Ultimately 189 treatment
and 166 control participants.
• Outcomes: Income support recipiency; DEEWR
program expenditure; Employment status;
Housing status; Self-rated health and well-being;
Participation in community activities. [Use both
administrative data and own-survey data.]
Measured 1, 2 and 3 years after
commencement.
b. Main findings
• Little evidence of effect of YP4 on outcomes
(Even when seek to assess effect of length of
treatment) => ‘You get what you pay for’.
c. Lessons we learned:
• Need to ask: Is the intervention worth studying?
• The importance of ‘pre-testing’ eligibility criteria
• The difficulty of ensuring randomisation happens
• The importance of collecting data along the way
4. Case study 2: EYEP – The early years
education program
a. Main features:
• Intervention: Children receive 5 days per week
of high-quality education and care totalling at
least 25 hours – for 3 years. Key features - High
staff/child ratios, qualified staff, rigorously
developed curriculum, use of relationship-based
pedagogy; and focus on alliance with parents.
• Partner: Project undertaken at initiative of and
managed by Children’s Protection Society.
• Eligibility: Children must be aged from 0 to 3
years, and assessed as having two or more risk
factors in the Department of Human Services
(DHS) Best Interest Practice Guidelines (eg.,
having teenage parents, parental substance
abuse, and the presence of family violence).
• Timing: Recruitment commenced in 2011, to be
completed by end of 2013. Data collection will
be complete by the end of 2016.
• Size of trial: Target of 45 treatment and 45
control participants.
• Outcomes: Data collected on children include
measures of physical and mental health, child
development, language development and
service usage - via standardized assessments,
parent and childcare educator questionnaires,
and observation and interviews. Measured 1, 2
and 3 years after commencement. Use of data
from LSAC provides an extra control group.
b. Lessons we have learned:
• Need for ‘champion(s)’ within organisation who
have authority
• Role of research committee
• The importance of a pilot phase
• One model for ensuring randomisation happens
• Implementing trial via dedicated high-quality
researcher who is independent of provision of
the program
• Scope for partner selection bias
5. Criteria for determining feasibility and
value
• Is the intervention worth studying? (Cost-benefit
of doing the trial versus the gain to society from
better policy-making. Some factors to consider:
Size and scope of intervention; What is known
already?; What can be learned using alternative
approaches?)
• Is it ethical?
• Is it possible to implement a RCT? (Can think
creatively: Early partial roll-out; Differences in
dosage between regions/population groups)
6. Designing and conducting a RCT
• A big message: Need to think about the right
approach for evaluation on a case-by-case basis
• Another big message: Worry about design and
implementation. Get the management right.
• (i) Starting off:
• Put together a research committee
• Define policy you are interested in testing and its
expected benefits
• Understand theory and relevant existing research
• (ii) Getting into the details of design:
• Define the intervention(s) – What happens to
treatment group? What happens to control
group? Ways of dealing with substitution bias?
• Defining outcome measures
• Defining eligibility (What will be external
validity?)
• Efficacy versus effectiveness (eg., partner
selection bias)
• Choosing a process for randomisation
• Deciding on size of trial
• How will data on outcomes be collected?
• How to minimise drop-out?
• (iii) Implementation:
• Doing a pilot
• Create a culture of ‘doing it right’ (eg.,
commitment of partner organisations; getting the
researcher(s) who will implement the trial).
• Monitoring implementation of intervention
• (iv) Reporting on the trial:
• Protocol for reporting on trial
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