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Implementation of Randomized Trials

Implementation of Randomized Trials. David Myers American Institutes for Research Washington, DC Prepared for IES/NCER Summer Research Training Institute, 2008. Context. Conducting effectiveness trials and not efficacy trials

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Implementation of Randomized Trials

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  1. Implementation of Randomized Trials David Myers American Institutes for Research Washington, DC Prepared for IES/NCER Summer Research Training Institute, 2008

  2. Context • Conducting effectiveness trials and not efficacy trials • Design and implementation of random assignment should not distort the program/intervention or the population served • Programs should run at capacity

  3. Illustrative Studies: Personal Involvement • Upward Bound • Nationally representative study • 67 sites and more than 3,000 students • Student RA within site • http://www.mathematica-mpr.com/publications/PDFs/upboundimpact.pdf • Workplace Literacy • 3 sites and about 500 adult learners • Learner RA within site • "Addressing Literacy Needs at Work: Implementation and Impact of Workplace Literacy Programs. Final Report." Washington, DC: Mathematica Policy Research, Inc., October 1998

  4. Illustrative Studies: Personal Involvement • 21st Century Community Learning Centers • 12 grantees (elementary school study) • Student RA within site • http://www.mathematica-mpr.com/publications/PDFs/elementaryschools.pdf • NYC Voucher Experiment • 2000 students • Family RA • http://www.mathematica-mpr.com/publications/PDFs/nycfull.pdf

  5. Illustrative Studies: Personal Involvement • Reading Comprehension • 10 districts and 40 schools • School RA • http://www.mathematica-mpr.com/publications/PDFs/readcomp.pdf • Closing the Reading Gap • 32 schools (4 interventions) • Student RA to reading groups within schools • http://ies.ed.gov/ncee/pdf/20084013.pdf

  6. Illustrative Studies: Personal Involvement • Quantum Opportunities • 7 sites and about 1000 students • Student RA within site • http://www.mathematica-mpr.com/publications/PDFs/QOPfinalimpacts.pdf

  7. Practical Problems in Implementation • Technical • Political and Ethical Challenges • Recruitment (not independent of P and E Challenges)

  8. Further Exploration: Technical • Cross-overs • Members of C get into T or something like T (use UB example and James Comer example) • Into T -- straight forward adjustment (AIR, 1996) • Something like T -- ?; affects interpretation • Attrition • Post baseline -- “straight forward” adjustment (e.g., MI) • Before baseline -- problematic, no information • How to fix?????

  9. Further Exploration: Technical • Unbalanced designs • Don’t demand additional recruitment • Large variance in selection probabilities (weights) • “over subscription” didn’t meet expectations (UB example) • Dishonest assignment -- post randomization • Sites don’t tell all students they have been selected for the program (UB example) • Sites ignore RA and move controls into T

  10. Further Exploration: Ethical and Political Challenges • Random assignment isn’t fair • Programs afraid of denying services to students • Is it fair to never give a student a chance? (UB example) • Random assignment will force a program/teacher to serve a different population • Role of stratification to serve the desired mix • Some students (units) must be served • Role of the “wild card” before randomization • Wild cards excluded from analysis

  11. Further Exploration: Ethical and Political Challenges • All “seats” must be filled • Role of the waiting list • Random selection within strata, if needed and desired by program operators • T and C groups analyzed as implemented at initial randomization • When programs believe recruitment will distort the population • Identify “most likely” and “least likely” to serve • Prior to randomization and stratify in analysis

  12. Further Exploration: Ethical and Political Challenges • New treatments/interventions are hard to sell • Core programs vs. supplemental programs • Does the core program align with other curriculum and state assessments? • Concerns about making AYP • Will a supplemental program reduce hours of instruction in a core area such as ELA?

  13. Strategies for Recruitment: Schools • Start with assistant superintendent for instruction (reading, math, science) or someone of similar stature • Quickly develop a relationship with an office and not just an individual -- staff come and go • Determine who needs to approve and to buy into participation • Superintendent -- they may need to go to the school board • Principals • Teachers • Parents and community groups

  14. Strategies for Recruitment: Schools • Be prepared to meet with them • Have a recruitment team • Technical expertise in the design • Be prepared to tell audience why RA is valuable and not in a technical sense! • Deep knowledge about the intervention -- most important • Example of a meeting (next slide)

  15. Irrefutable Evidence

  16. Strategies for Recruitment: Schools • Establish expectations for the researchers and the schools • Minimize legal talk • Will bring in their general counsel and … . • Responsibilities and timelines • Obtaining consent • Data collection • Administering instruments and tests • Answering questions from parents and others

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