CMS-10316 - Supporting Statement part B

SUPPORTING STATEMENT PART B

Implementation of the Medicare Prescription Drug Plan (PDP) and Medicare

Advantage (MA) Plan Disenrollment Reasons Survey

B. Collection of Information Employing Statistical Methods

B1. Respondent Universe and Sample

A total of 176,985 disenrollees from December 2012 through February 2014 will be sampled (covering 15 months of disenrollment activity) using a “modified probability proportional to size (PPS) sampling approach” with a floor on the sample per contract, and larger samples drawn from biggest contracts. The advantage of this approach is that it provides an efficient nationally representative sample of all enrollees, while allowing for adequate sample in smaller included contracts to identify contracts with outlying scores on relevant measures. This approach will generate more precision in larger contracts, where so much of total enrollment lies (particularly for MA-PD). We need to have enough sample from these large contracts so as not to hinder our ability to make accurate national subgroup estimates. In some cases, we anticipate that there will be no sample in some very small contracts, although we will strive to make inferences for as many small contracts as possible.

The basic PPS design (used successfully in sampling for Medicare CAHPS) is implemented in two stages-- first selection of included contracts or sponsors, and second selection of individuals within selected contracts. Let N represent the number of eligible disenrollees in a contract, and n the sample size that will be drawn (by simple random sampling) within that contract. Furthermore let N* be a cutoff disenrollee count and n* a minimum sample size. The sampling proceeds with slightly different rules for depending on N:

 Large contracts (by size of disenrollment ) (N > N*):

o Probability of contract selection = 1

o Sample size n = (N/N*) n*. [enlarged sample proportional to size]

 Medium contracts (n* < N < N*):

o Probability of contract selection = N/N*

o Sample size n = n* [standard target sample size]

 Small contracts ( N < n* ):

o Probability of contract selection = n*/N*

o Sample size n = N [sample all available cases]

Exact sampling figures will be determined upon receipt of data regarding disenrollment patterns.

Sampling weights reflect the probability that each beneficiary is selected for the survey; nonresponse weights reflect the probability that a sampled beneficiary responds to the survey; poststratification weights make the respondent sample’s characteristics more similar to the population. Sampling weights are readily calculated as the ratio of eligible to sampled beneficiaries in each contract. Simple contract-level poststratification weights will be calculated as the ratio of eligible to responding beneficiaries in each contract. More complex individual-level nonresponse or poststratification weights will be developed using logistic regression and raking/log linear models, respectively. We will develop weights appropriate to national and subgroup comparisons.

B2. Information Collection Procedures

Each cohort will have a 12 week data collection period. The primary mode of data collection will be a mail survey. Beneficiaries will be mailed a survey packet with a cover letter signed by the CMS privacy officer (see attachment 1 for a copy of the wave 1 cover letter). Four weeks after the initial survey mailing, beneficiaries will be mailed a follow- up survey packet with a modified cover letter signed by the CMS privacy officer (see attachment 2 for a copy of the wave 2 letter).

B3. Methods to Maximize Response Rates

We anticipate a response rate of 60 percent, based on prior disenrollment surveys and recent experience with surveys of Medicare beneficiaries. We will employ multiple mail contacts to minimize non-response.

B4. Tests of Procedures or Methods

No tests of procedures or methods will be undertaken as part of this data collection.

B5. Statistical and Questionnaire Design Consultants

The survey, sampling approach, and data collection procedures were designed by the RAND Corporation under the leadership of:

Cheryl Damberg, Ph.D. Senior Policy Researcher RAND Corporation

1776 Main Street

PO Box 2138

Santa Monica, CA 90407-2138

310-393-0411

Data will be collected by the survey vendor CSS Research under the direction of: Jeff Burkeen

CSS Research

1625 K Street NW, 8th Floor

Washington, DC 20006

202-454-3005

1