OMB No. 0960-0747
The AB demonstration project will be limited to new SSDI beneficiaries who meet the following criteria: (1) they are uninsured, (2) they are not currently receiving Supplemental Security Income (and thus eligible for Medicaid), (3) they are not currently receiving Medicare (for example, some new SSDI beneficiaries are exempted from the waiting period for entitlement to Medicare because they suffer from end-stage renal disease), (4) they live in one of 53 selected metropolitan areas, and (5) for those new SSDI beneficiaries who are in the waiting period, the onset of their disability occurred recently enough that they have at least 18 months before they will be eligible for Medicare.
Information on each of the criteria can be obtained from SSA administrative records except for whether an individual is uninsured. The first step in choosing the sample will therefore be to use SSA administrative records to obtain a list of all new SSDI-only beneficiaries who meet all other criteria and whose disability onset was no more than nine months prior. Because new SSDI beneficiaries are eligible for Medicare 29 months after disability onset, the last restriction would allow us two months to locate and screen the beneficiary and obtain consent, and still have 18 months of eligibility for AB remaining.
Recruitment took place between October 2007 and January 2009. All beneficiaries who receive the AB health plan (AB-Basic or AB-Plus) and a sample of 717 control group members (n = 1,734) are eligible to participate in the twelve-month follow-up survey.
All AB-Basic and AB-Plus participants will be included in the 12-month follow-up survey. In addition, all 625 control group members randomized while AB-Plus participants were recruited will be included in the survey. However, only 92 of the 368 control group members randomized after that point will be included in the survey to balance the 92 AB-Basic members recruited after that point. All sample members will be mailed an advance letter and FAQs. We will then attempt to contact sample members by telephone. Non-respondents will be assigned to field staff who will first attempt to locate study participants and will encourage them to complete their interview by telephone. Field staff will provide sample members with a cell phone that they can use to complete the interview on-the-spot, if necessary.
a. Random Assignment Demonstration Study
The main analytical strategy in the impact analysis will be to compare outcomes among those randomly assigned to the three research groups (AB-Plus, AB-Basic, and the control group). To increase statistical precision, comparisons will be regression-adjusted for baseline characteristics such as primary impairment, time since disability onset, self-reported health status, and prior work history.
As described earlier, we expect to attempt to survey all 617 AB-Plus and all 400 AB-Basic members along with 717 control group members. This will allow us to have an 80 percent chance of generating statistically significant findings of the effects of AB- Plus compared to the control group if the true impact on an outcome is .158 standard deviations using the measures from the 12-month follow-up survey.1 In comparing AB-Basic to AB-Plus, the minimum detectable effect is .194 standard deviations. In comparing the AB-Basic to the control group, the minimum detectable effect is .175 standard deviations. For example, if 4 percent of the control group earns above Significant Gainful Activity (SGA), the study would have an 80 percent chance of generating a statistically significant impact estimate of AB-Plus if the true impact is 3.1 percentage points. It would likewise have an 80 percent chance of generating a statistically significant impact estimate of AB-Basic if the true impact of AB-Basic health plan is 3.4 percentage points.
We will rely on our experience conducting disability surveys to develop procedures that will maximize the response rates obtained. These procedures will include:
Multiple methods for tracking and locating beneficiaries, including the use of extracts from SSA administrative data to capture address updates during the course of the survey, the use of an independent vendor providing commercially available contact information, combined with MPR’s internal respondent tracking efforts to locate beneficiaries.
The availability of additional flexible response options, including TTY, TRS and instant messaging to facilitate the participation of respondents with hearing impairments.
Interviewer training that stresses the importance of respondent cooperation, and develops skills for averting and converting refusals.
Interviewer training on when and how to select an appropriate proxy to conduct the interview.
A bilingual module to help bilingual interviewers assess whether to conduct an interview in Spanish or English, and to cover differences in dialects.
Protocols for breaking off and then resuming interviews to accommodate beneficiaries who may become fatigued during the interview.
A single-mode approach that will use the most cost-effective approach (CATI) followed by in-person locating for non-respondents.
a. Pretest
The draft twelve-month follow-up instrument was pre-tested to assess the data collection process, evaluate the clarity of the questions asked, identify possible modifications to either question wording or question order that could improve the quality of the outcome data, identify and eliminate problems with specific questionnaire items, including skip errors prior to programming the instrument for CATI, and estimate respondent burden. In addition to monitoring the pretest interviews to identify questions that are problematic for interviewers or respondents, we conducted an interviewer debriefing upon completion of the pretest. New questions (not used in previous, similar surveys) were scrutinized especially closely during the pretest. MPR on-call staff served as both interviewers and respondents during the pretest. Testing with the target population, AB demonstration participants, was not feasible. Similarly, we could not recruit uninsured SSDI beneficiaries for the pretest while the enrollment period is still underway for the demonstration. Also, since many of the questions were used at baseline and at the six-month follow up, this approach made sense. A total of nine pretest interviews were conducted.
On average, the baseline questionnaire took 45 minutes to administer, with a range of 35 to 50 minutes. The pretest was conducted using paper and pencil administration. Since many of the questions were used previously, the pretest uncovered few problems. We implemented some relatively minor modifications to the questionnaire based on the findings from the pretest. A more detailed description of the findings from the pretest is included in Appendix F.
Charles Michalopoulus, MDRC
Frank Potter, MPR
1These minimum detectable effects are for a two-tailed t-test at the 10 percent significance level and have not been regression adjusted for baseline characteristics or for having multiple comparisons (multiple outcomes and comparisons across three research groups).
0960-0747 Supporting Statement B
| File Type | application/msword |
| File Title | SUPPORTING STATEMENT B |
| Author | 666429 |
| Last Modified By | 666429 |
| File Modified | 2008-12-30 |
| File Created | 2008-12-30 |