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Self-Sufficiency Project
Last registered on May 25, 2017


Trial Information
General Information
Self-Sufficiency Project
Initial registration date
May 25, 2017
Last updated
May 25, 2017 5:48 PM EDT
Primary Investigator
Social Research and Demonstration Corporation
Other Primary Investigator(s)
PI Affiliation
Additional Trial Information
Start date
End date
Secondary IDs
The Self-Sufficiency Project (SSP) was a research and demonstration project designed to test a policy innovation that makes work pay better than welfare. Conceived and funded by Human Resources Development Canada (HRDC), managed by the Social Research and Demonstration Corporation (SRDC), and evaluated by the Manpower Demonstration Research Corporation (MDRC) and SRDC, SSP offered a temporary earnings supplement to selected long-term income assistance (IA) recipients in British Columbia and New Brunswick. The earnings supplement was a monthly cash payment available to single parents who had been on income assistance for at least one year and who left income assistance for full-time work. The supplement was paid on top of earnings from employment for up to three years, as long as the person continued to work full time and remained off income assistance. While collecting the supplement, the single parent received an immediate payoff from work; for a person working full time at the minimum wage, total income before taxes was about twice her earnings.

To measure the effects of its financial incentive, SSP was designed as a social experiment using a rigorous, random assignment research design. A group of about 6,000 single parents in British Columbia and New Brunswick who had been on income assistance for at least a year was selected at random from the IA rolls. One half of these people were randomly assigned to a program group and offered the SSP supplement, while the remainder formed a control group.

The key questions are whether the SSP program increased parents’ earnings and income, whether it reduced reliance on welfare, whether it harmed or benefited children, how much it cost, and whether the supplement offer had ongoing effects in the period after parents were no longer eligible to receive it.
Registration Citation
Ford, Reuben and Charles Michalopoulos. 2017. "Self-Sufficiency Project." AEA RCT Registry. May 25. https://doi.org/10.1257/rct.2042-1.0.
Former Citation
Ford, Reuben, Reuben Ford and Charles Michalopoulos. 2017. "Self-Sufficiency Project." AEA RCT Registry. May 25. http://www.socialscienceregistry.org/trials/2042/history/18021.
Experimental Details
The key features of the earnings supplement program were:

-- Full-time work requirement. Supplement payments were made only to eligible single parents who worked full time (an average of at least 30 hours per week over a four-week or monthly accounting period, whether in one or more jobs) and who left income assistance. The full-time work requirement ensured that (1) supplement recipients were preparing for self-sufficiency, since most IA recipients would have to work full time in order to earn enough to remain off income assistance; (2) most supplement recipients needed to increase their work effort to qualify, since few IA recipients already worked full time; and (3) earnings were substantial enough so that earnings plus the supplement payment represented a large increase in income for most people receiving the supplement.

-- Substantial financial incentive. The supplement was calculated as half the difference between a participant’s earnings from employment and an “earnings benchmark” set by SSP for each province. The benchmark for each province was set at a level that would make full-time work pay better than income assistance for most recipients. During the first year of operations, the benchmark was $37,000 in British Columbia and $30,000 in New Brunswick. Therefore, for example, a participant in British Columbia who worked 35 hours per week at $7 per hour earned $12,740 per year and collected an earnings supplement of $12,130 per year ($37,000 minus $12,740, divided by 2), which adds up to a total gross income of $24,870. Unearned income (such as child support) or earnings of other family members did not affect the amount of the supplement. When tax obligations and tax credits were taken into account, most families had incomes $3,000 to $7,000 per year higher with the earnings supplement program than if they worked the same number of hours and remained on income assistance.

-- Gradual reduction in benefits as earnings increase. Reductions in the supplement amount occurred more gradually than they do in the case of IA benefits. The supplement was reduced by 50 cents for every dollar of increased earnings, following the supplement-calculation formula described above. The supplement was fully phased out only at the earnings-benchmark levels.

-- Availability to single-parent families only. Recruitment for the study was limited to single parents for several reasons. First, single-parent families make up a substantial proportion of the IA caseload. Second, single parents (particularly those with young children) face considerable barriers to full-time employment and are often considered “unemployable” by the welfare system. Thus, they constitute an important target group for any new policy that attempts to increase self-sufficiency. Third, given the project’s budget constraints, it was impossible to include enough cases of all types of households on welfare to permit an accurate analysis of the supplement program’s effects on each of them.

-- Availability to long-term welfare recipients only. The supplement was offered only to single-parent families who had been on income assistance for 12 months in a 13-month period. Eligibility for the supplement was limited to these relatively long-term welfare recipients for three main reasons. First, long-term welfare recipients account for a disproportionate share of welfare costs, making them a critical group to target. Second, extending eligibility to people who had received income assistance for less than a year would probably have resulted in a large share of program resources being spent on supplement payments to people who, even in the absence of the program, would have left welfare after a short time. Third, the one-year IA receipt requirement reduced the potential that the program would attract people onto the welfare rolls for the purpose of being able to receive the supplement.

-- One-year period to take advantage of the offer. Once an IA recipient was selected to join the program group, she was informed that if she found full-time work within the next 12 months and agreed to leave income assistance, she could sign up for the supplement. If she did not sign up within 12 months, she became ineligible for the supplement. This requirement discouraged delay in responding to the supplement offer but gave people time to consider the offer and to find employment. The 12-month period in which program group members could qualify for the supplement is sometimes referred to as the “one-year take-up window.”

-- Three-year time limit on supplement receipt. A person could have collected the supplement for up to three years from the time she began receiving it, as long as she was working full time and not receiving income assistance. The three-year time limit on supplement receipt eliminated the possibility of long-term dependence on the program.

-- Voluntary alternative to welfare. People could not receive IA payments while receiving the supplement. However, no one was required to participate in the supplement program. After beginning supplement receipt, people could decide at any time to return to income assistance, as long as they gave up supplement receipt and met the IA eligibility requirements. They could also renew their supplement receipt by going back to work full time at any point during the three-year period in which they were eligible to receive the supplement (also referred to as the “three-year supplement receipt period” or “three-year supplement period”).
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Employment, earnings, income
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
A group of about 6,000 single parents in British Columbia and New Brunswick who had been on income assistance for at least a year was selected at random from the IA rolls. One half of these people were randomly assigned to a program group and offered the SSP supplement, while the remainder formed a control group.

Recruitment into SSP’s main research study began in November 1992 and was completed in March 1995. Each month, Statistics Canada used IA administrative records to identify all people in selected geographic areas in British Columbia and New Brunswick who (1) were
single parents, (2) were 19 years of age or older, and (3) had received IA payments in the current month and at least 11 of the prior 12 months. No other restrictions (for example, on health status) were imposed. Statistics Canada then randomly selected a “fielding sample” to contact, interview, and invite to be part of the SSP study.

The SSP evaluation also included two special studies. The SSP applicant study examined the effects of SSP for parents who had just begun receiving welfare in British Columbia. The sample for the applicant study consisted of 3,316 new IA recipients in British Columbia who were randomly assigned to a program group and a control group. Program group members were informed that if they continued to receive income assistance for one year, they would then be given the opportunity to participate in SSP’s earnings supplement program.

The second special study, the SSP Plus study, examined the effect of combining the earnings supplement with other services. For this, 293 sample members in New Brunswick were randomly assigned to the SSP Plus group. In addition to the opportunity to participate in the earnings supplement program, SSP Plus group members received services such as job clubs, assistance in résumé preparation, and individual job-search coaching. Outcomes for the SSP Plus group were compared with those for the members of the main study’s program group and control group who were randomly assigned in New Brunswick during the same period.
Experimental Design Details
Randomization Method
Randomization done in office by a computer
Randomization Unit
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
Sample size: planned number of observations
5,729 single parent welfare recipients and 3,315 single parent welfare applicants
Sample size (or number of clusters) by treatment arms
Recipients study
2,849 individuals control, 2,880 individuals program
Random assignment was 50/50 program/control except for those joining the study between November 1994 and March 1995 in New Brunswick, who were randomly assigned to program, control, or SSP Plus. A total of 293 participants were assigned to SSP Plus.

Applicants study
1,667 individuals control, 1,648 individuals program
Random assignment was 50/50 program/control in British Columbia only.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Intervention Completion Date
January 31, 1999, 12:00 AM +00:00
Is data collection complete?
Data Collection Completion Date
Final Sample Size: Number of Clusters (Unit of Randomization)
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
5,685 individuals; 4,852 (84.7%) completed the final, 54-month survey
Final Sample Size (or Number of Clusters) by Treatment Arms
2,392 control, 2,460 program
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)
SSP substantially increased full-time employment, earnings, and income and reduced the poverty rate--all at a low net cost to the government. The program also improved the school performance of enrollees' elementary school-aged children, a benefit that--unlike the positive economic effects--persisted even after parents stopped receiving the supplement.
Michalopoulos, Charles, Doug Tattrie, Cynthia Miller, Philip K. Robins, Pamela Morris, David Gyarmati, Cindy Redcross, Kelly Foley, and Reuben Ford. 2002. Final Report on the Self-Sufficiency Project for Long-Term Welfare Recipients. Ottawa: Social Research and Demonstration Corporation.