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- The study’s objective was to assess the effect of a retirement planning aid on encouraging new hires at a large institution to enroll in a supplemental retirement account (SRA). The authors presented results from both an initial pilot test and a full-scale implementation using a modified version of the planning aid.
- The authors compared the mean 30- and 60-day enrollment rates of cohorts of new hires using administrative data provided by the institution.
- The final version of the planning aid increased SRA enrollment considerably relative to the control group, with more than 27 percent of new hires enrolling within 30 days and more than 41 percent enrolling within 60 days, compared with 7 and 29 percent, respectively, in the control group. Results were similar during the pilot intervention phase.
- The quality of causal evidence provided in this study is low. This means that we are not confident that the estimated effects are attributable to the planning aid; other factors are likely to have contributed.
A Retirement Planning Tool
- The pilot planning aid increased SRA enrollment significantly. More than 21 percent of the second cohort enrolled within 30 days of hire and nearly 45 percent enrolled within 60 days, compared with 7 and 29 percent, respectively, of cohort one.
- The streamlined planning aid led to similar increases in SRA enrollment. More than 27 percent of new hires in cohort three enrolled in an SRA within 30 days and more than 41 percent enrolled within 60 days.
Considerations for Interpreting the Findings
The authors compared average enrollment rates across cohorts and did not adjust in any way for cohort characteristics. Because the control and treatment groups in the first intervention fell along a chronological continuum, the effects of the planning aid were estimated in an interrupted time series framework. The authors conducted only a single demonstration of the intervention and did not provide any evidence to suggest that its timing was independent of prior trends, so it is possible that the intervention coincided with other events that might have affected the observed enrollment rates.
The comparison and treatment groups in the contrast of cohorts one and three were separated in time and thus do not constitute an interrupted time series design. In this case, the lack of statistical controls for possible systematic differences between the two groups introduced a range of other factors that could also account for the observed differences in enrollment rates.
Causal Evidence Rating
The quality of causal evidence provided in this study is low. This means that we are not confident that the estimated effects are attributable to the planning aid; other factors are likely to have contributed.