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Police Recruitment Communications Intervention: Reducing Drop Off at PHS stage
Last registered on November 07, 2017


Trial Information
General Information
Police Recruitment Communications Intervention: Reducing Drop Off at PHS stage
Initial registration date
November 06, 2017
Last updated
November 07, 2017 4:35 PM EST
Primary Investigator
Goldman School of Public Policy, UC Berkeley
Other Primary Investigator(s)
PI Affiliation
Assistant Professor, Goldman School of Public Policy
Additional Trial Information
In development
Start date
End date
Secondary IDs
Candidates applying to the police force must pass various assessments to become eligible for the academy. After entering the process, there is drop-off at each stage. The large police department with which we work has a particularly substantial number of drop outs at the stage where candidates must submit a Personal History Statement (PHS) as part of the Background Investigation phase. In our randomized controlled trial, we administer a communications intervention to candidates, encouraging and reminding them to submit their PHS online. Candidates are randomized into treatment and control groups at the individual level, with the control group receiving the existing personnel department email regarding next steps. The treatment group receives a new email as well as a follow up text message reminding candidates to submit the PHS. We compare the yield rate and length of time from email to PHS submission to determine treatment effect.
External Link(s)
Registration Citation
Linos, Elizabeth and Nefara Riesch. 2017. "Police Recruitment Communications Intervention: Reducing Drop Off at PHS stage ." AEA RCT Registry. November 07. https://doi.org/10.1257/rct.2564-1.0.
Former Citation
Linos, Elizabeth, Nefara Riesch and Nefara Riesch. 2017. "Police Recruitment Communications Intervention: Reducing Drop Off at PHS stage ." AEA RCT Registry. November 07. http://www.socialscienceregistry.org/trials/2564/history/22999.
Experimental Details
Candidates who pass the Personal Qualification Essay (the previous stage in the selection process) will be notified via email. This email will contain the candidate's score and an invitation to complete the Personal History Statement, as part of the Background Investigation stage. The control group will receive the existing email from the personnel department, which includes an automated appointment time for the PHS (which can be administered in-person or submitted via online application or email). The treatment email will encourage applicants to submit the PHS through the online application and gives the candidate an automatically generated 2-week deadline from the date of the email. One week later, applicants in the treatment group will receive a text message reminder to submit by the deadline. The control group will not receive a text message reminder.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
The main outcomes of interest are (1) whether a candidate who passed the PQE submitted the PHS within two weeks and (2) whether the candidate submitted online.
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
We will also consider interaction effects between candidate outcomes and their demographics (race, gender, age).
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
Candidates will be randomized into groups with individual-level randomization. The control group will receive current emails as per "business as usual". The treatment group will receive a revamped email and a text message reminder.
Experimental Design Details
We will be splitting the eligible group into a control and experimental group based on the final digit of their candidate identification number (a unique identifier that stays with an applicant, irrespective of how many times they apply). “Randomization” will occur on a weekly basis, to match email batches that go out every Friday. Candidates who receive the treatment email will also receive a text message reminder to submit the PHS a week prior to the suggested two-week window closure. For statistical power, we expect to run the trial for five months to get at least 3136 participants.
Randomization Method
Candidates will receive computer generated identification numbers when they begin the application process. Candidates will be split into either treatment or control based on the last digit of their identification number.
Randomization Unit
Randomization will occur at the individual level.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
There are no clusters
Sample size: planned number of observations
We expect approximately 3100 individuals although there will be expected variation in the total number of candidates involved.
Sample size (or number of clusters) by treatment arms
We anticipate a little over 1560 individuals in each group.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
5 percentage point change in PHS submissions (with a conservative estimate of 50% baseline compliance)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Is data collection complete?
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)