the 2015 and 2016 waves. In the 2016 survey round, the information inervention end-line, 28.3 percent of respondents from the 2015 baseline had attrited from the sample.

# **3.2 Information Intervention**

To provide relevant information to migrants randomly selected for treatment, pamphlets were developed through extensive consultations with relevant program managers and staff responsible for administering health insurance and pension programs in each city. This pamphlet discusses city-specific features of health insurance and pension programs, and summarizes program rules, which vary significantly across cities and for different categories of employment (e.g., wage employment and self-employment). In discussions with local bureaucrats, the rules, premiums, and the benefits for each type of worker (as shown in Online Appendix A.2) were verified. Online Appendix A.3 provides an example of the easy-to-understand pamphlet provided as a guide to workers in Dongguan. In addition, the pamphlets use lay terms to highlight the risk-management benefits of participating in pension and health insurance programs.

The information intervention was implemented between early December 2015 and the end of January 2016. The city-specific information pamphlets were distributed to a randomly selected sample of 35% of the 2015 RUMiC sample in 12 of 15 survey cities (and the randomization was done within cities). As the Shanghai RUMiC sample size is significantly larger than the rest of the cities, we randomly selected 25% rather than 35% of the 2015 sample for treatment. This decision was driven by cost and time considerations.<sup>10</sup> The information intervention was implemented by 33 enumerators, of which 64% were university students (either undergraduate or graduate) and the rest were RUMiC survey firm enumerators.<sup>11</sup> In each city, enumerators received classroom and field training from one of the coauthors over a two day period. In the intervention, enumerators first presented a small gift and an information pamphlet to each of the randomly selected sample respondents. After a short introduction, the enumerator read a brief summary of the benefits and costs of participating in pension and health insurance programs from the first page of the pamphlet.

> 10The 2015 survey was completed later than previous rounds, and the Guangzhou and Zhengzhou surveys ran through the end of 2015 with data available even later. These cities were not included in the intervention because there was not sufficient time to both distribute the pamphlets and allow respondents time to react before the 2016 RUMiC survey. In addition, within the 13 included cities, households lacking a working migrant worker, defined as someone with a rural _hukou_ and currently working and not retired (aged 16-55 for women and 16-60 for men), are excluded from the random selection for the intervention sample. Further, 8 households (from both treatment and control groups), were not included because their homes were too far from the city center. In total we excluded 304 households, which accounted for 6.9% of households in the 13-city sample.

> 11Of the 13 cities, 8 used enumerators from the survey firm and 5 used students. When students were used as enumerators, a person from the survey firm was hired to accompany students to the enumeration site to insure that the target respondent was interviewed.

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