Medicare beneficiaries’ knowledge of and choices regarding Part D, 2005 – present

Abstract

In the months before and years since Medicare Part D’s implementation in January 2006, many have been concerned with beneficiaries’ ability to benefit from the complex program. We undertook a systematic review of published Medline and grey literature from January 1, 2005 -August 20, 2009 in order to evaluate Medicare beneficiaries’ knowledge about Part D and how this knowledge informed decisions regarding enrollment and plan choice. We included 30 articles that reported original results describing either seniors’ knowledge of the Part D benefit, decision to enroll, and/or selection of plans, that reported results from patient surveys addressing these issues, or that analyzed actual enrollment data or plan selection patterns. Of these 30 articles, 10 described beneficiaries’ knowledge, 12 described enrollment and plan choices and 8 concerned both knowledge and choice. Across studies and years, beneficiaries’ knowledge of the Part D program and benefit structure/design was poor, particularly with regards to the coverage gap and the low-income subsidy. Beneficiaries had great difficulty choosing the lowest cost Part D plans and were disinclined to switch plans to improve their benefits. Knowledge deficits, enrollment problems, and plan choice difficulties were most pronounced during Part D implementation in early 2006, but also persisted in subsequent years of the benefit. Beneficiaries’ knowledge and choices should be monitored on an ongoing basis to inform potential changes to the Part D program.

BACKGROUND

The implementation of Medicare Part D in January 2006 offered seniors improved access to prescription drug insurance. At least one-quarter of elderly Medicare beneficiaries had no previous drug insurance,¹ and 22.5 million beneficiaries (53%) were enrolled in the benefit by June 2006.² In the months prior to Part D’s inception, and in the months and years since, researchers, policymakers, and patient advocates have fiercely debated elderly beneficiaries’ ability to navigate and benefit from the unique features of the Medicare Part D program.^{3, 4} Many have complained that the benefit is too complex:³ the benefit is administered by numerous private insurers; seniors must choose among over 40 plans in each geographic area;⁵ each plan uses an array of drug formulary and cost sharing mechanisms⁶ which insurers may change at any time;^{7, 8} and the standard benefit includes a gap in coverage during which beneficiaries are responsible for 100% of drug costs (the coverage gap).⁹ Beneficiaries with incomes below certain thresholds can apply for a low-income subsidy (LIS) to help ease the cost-sharing burden, but this process can be cumbersome and confusing.¹⁰ The intricacies of the Part D benefit may present information challenges for even the savviest Medicare beneficiary.

In this systematic review, we evaluate data from 2005 to the present regarding beneficiaries’ knowledge about Part D both before and after the benefit began. We examine how beneficiaries used their knowledge to choose Part D plans and the extent to which beneficiaries’ plan choices were aligned with their health and financial interests. We also assess beneficiaries’ responses to sub-optimal plan choices when they have the opportunity to switch plans. We discuss our findings’ implications for the future of the Part D program.

METHODS

Literature Search and Selection

A systematic search of the medical literature was performed to identify studies addressing seniors’ knowledge of the Medicare Part D prescription drug benefit, their choice to enroll, and their selection of Part D plans. The initial searches were limited to articles published in Medline between January 1, 2005, one year before the Part D benefit was implemented, and August 20, 2009. Our search used three main subject heading domains: terms relating to Medicare Part D (for example, [Medicare AND drug benefit OR drug plan OR prescription], OR Part D, OR Medicare Modernization Act, OR MMA), terms relating to knowledge (for example know$, OR understand$, OR comprehen$) and terms related to decisions to enroll or plan selection (for example: choice, OR choose, OR enroll$, or participat$, OR decide, OR select$, OR access, OR, utiliz$). Articles containing at least one search term regarding Part D and at least one search term from one of the other two categories were included in the review.

We also searched the “grey literature” for original reports using the same criteria. Our search included the websites of the Kaiser Family Foundation, General Accounting Office, Families USA, Congressional Budget Office, Centers for Medicare and Medicaid Services (CMS), Congressional Testimony, AARP, the Commonwealth Fund, and Avalere Health. We reference mined articles included from our initial search and sought input from an expert at CMS (A.B.) who had accumulated relevant articles.

Articles were included if they reported original results describing either seniors’ knowledge of the Part D benefit, their decision to enroll, and/or selection of plans. Articles were included if they reported results from patient surveys explicitly addressing these issues or if actual enrollment data were analyzed and plan selection or enrollment patterns were reported. We excluded all studies in which plan choice was simulated or modeled based on data prior to 2006.

Extraction of Study-Level Variables and Results

Two reviewers [W.S. and U.S.] evaluated the titles and abstracts of search results to identify potentially relevant articles. Complete articles were assessed for inclusion by two reviewers [J.P. and U.S.]. Data was extracted from selected articles by three reviewers [J.P., W.S., U.S.] and differences were resolved by consensus. Variables assessed included the key research questions in each study, characteristics of the patient population (i.e., sample size, sociodemographic characteristics), setting, study design (analysis of enrollment data or patient survey), results, and conclusions drawn.

Data Synthesis

Articles were grouped into 2 main categories: seniors’ knowledge about Part D plans and their choice of plans. We created evidence tables reporting results from each of these searches, one focusing on knowledge and the other focusing on choice. Several studies reported data relevant to both research questions and the relevant data from those studies were included in both tables. Based on common themes identified across articles, we further grouped studies into those that described knowledge of 1) the Part D program, 2) Part D’s benefit structure, cost sharing, and formularies, and 3) the low-income subsidy as well as those that described choices regarding 1) enrollment in Part D, 2) in which Part D plan to enroll, 3) switching Part D plans.

RESULTS

Of 489 potentially relevant abstracts and titles screened, 76 articles were evaluated in full, and 30 articles met all inclusion and exclusion criteria (Figure 1). These articles can be categorized as follows: 10 described beneficiaries’ knowledge of Part D,^11–20 12 described beneficiaries’ Part D choices,^{18, 21–31} and 8 articles concerned both beneficiary knowledge and choice.^32–39 Of the selected articles, 14 were from the peer-reviewed medical literature while the remaining were from the grey literature.

Figure 1.

Medicare beneficiaries’ knowledge about Part D (Table 1)

Table 1.

Medicare beneficiaries’ knowledge about Part D

Reference	Research Question	# of Subjects	Design	Results	Conclusion
Goedken AM, Urmie JM, Farris KB, Doucette WR (2009) 13	What are the characteristics of Medicare beneficiaries who intend to enroll in Part D?	1200 English speaking U.S. residents aged 65+ enrolled in Medicare	Online cross- sectional survey administered in October 2005	For every 1 year increase in age, beneficiaries were 3% less likely to enroll in Part D than were those of younger age. Persons in excellent health, compared to those of fair or poor health, were 52% less likely to enroll in Part D. Persons who already had drug coverage were 79% less likely to enroll in Part D than those who did not have coverage. Persons with a greater number of prescription drugs were 4% more likely to enroll than those with less. Persons with incomes ≥ $75,000 were half as likely to enroll as compared to persons with incomes < $15,000.	Younger age, fair or poor health, lack of drug coverage, greater use of prescription drugs, and low income were predictors of Medicare beneficiaries’ intentions to enroll in Part D.
Skarupski KA, Mendes de Leon CF, Barnes LL, Evans DE (2009) 36	Does knowledge of the Part D benefit differ among blacks and whites?	2,694 community-dwelling adults aged 65+ in Chicago; 1,784 are black, 910 are white	Cross-sectional interviews between April 2006 and October 2007	Among non-enrollees, Blacks were more likely than Whites to report having been unaware of the program (13.2% versus 2.4%), that the program was too difficult to understand (12.9% versus 1.4%), and being uncertain about which plan to choose (10.3% versus 2.2%).	Blacks in this community, in comparison to Whites, were more likely to express knowledge gaps or lack of awareness about the Part D program. These gaps may have hindered Part D enrollment.
Hsu J, Fung V, Price M et al. (2008) 15	What do beneficiaries know about Part D benefits and costs? Are they aware of the coverage gap?	N=1040 of 1388 eligible, 74.9% response rate. Community-dwelling Kaiser- Permanente Northern California Medicare Advantage beneficiaries aged 65+ who were not eligible for Medicaid and did not receive a low-income subsidy	Mailed questionniare sent in January 2007, supplemented by telephone interview	40% of beneficiaries were aware that their drug plan in 2006 included a coverage gap Beneficiaries’ awareness of gap increased with increases in their 2006 drug costs, especially if they entered the gap or the catastrophic coverage period. However, only 50% (95% CI, 43-58%) knew the monetary value of the coverage gap threshold within $250. Only 21% (95% CI, 15-26%) knew when the coverage gap ended within $400.	Beneficiaries in this Medicare Advantage plan have limited knowledge of Part D cost sharing, including limited knowledge of the coverage gap. The majority were unaware of Part D’s cost sharing structure unless they experienced it directly.
Summer L, Nemore P, Finberg J (2008) 18	What are Part D counselors’ opinions regarding policy and procedural changes that could enhance Part D program performance?	660 beneficiary contacts. 397/1707 (23%) on a list of individuals who assisted beneficiaries, 121 respond to forwarded email from another survey responder, 142 respond to GW Health Policy Institute request. Of the 660, 54% were beneficiary counselors, 8% were attorneys, 30% managed or directed organizations that assisted beneficiaries and the rest were health care providers and/or other interested parties	Electronic, cross- sectional survey in Fall 2006	23% of respondents said that beneficiaries found it difficult to get and understand information surrounding Part D. 83% of respondents reported that beneficiaries do not apply for the low-income subsidy because they did not know how to apply for it or feel they are ineligible, while 77% of respondents suggested that beneficiaries were not aware that a subsidy was available. Other challenges included complexity due to too many plan choices, misperceptions about ability to switch plans, computer system problems, coverage restrictions, affordability, and enrollment difficulties.	Program complexity poses a challenge for the beneficiaries that these counselors assist, especially surrounding enrollment and low- income subsidy requirements.
Hargrave E, Piya B, Hoadley J, Summer L, Thompson J (2008) 32	What have been the experiences of beneficiaries (and providers) in dealing with Part D?	73 community-dwelling beneficiaries enrolled in a Part D plan and used at least 2 prescription drugs in Denver, CO, Richmond, VA, and Portland, ME.	13 focus groups were conducted between July and October 2007.	Beneficiaries were generally satisfied with the Part D program. Most beneficiaries were aware of the coverage gap, but were confused about how the gap works and how to know when they were approaching it. Beneficiaries did not always understand what plan they were in, but said that they were aware of formularies. Many beneficiaries were not aware of or did not fully understand how the low income subsidy worked and who was eligible for it. Beneficiaries were hesitant to switch plans because of the complexity of the process or fear of the unknown.	For the most part, beneficiaries were satisfied with Part D, despite knowledge gaps. Others were unwilling to switch plans because they did not want to undergo the complex processes of selecting and learning to use a new plan and/or were fearful of making a decision that placed them in a worse plan.
Cronk A, Humphries TL, Delate T, Clark D, Morris B (2008) 10	What were the coping behaviors used by self- enrolled beneficiaries who reached the Part D coverage gap? How do these behaviors compare with those of Part D enrollees in a retiree drug subsidy plan who did not have a coverage gap but reached the gap threshold amount in 2006?	1472 participants with >=$2250 in total drug spending by October 1, 2006: 740 in the KPCO Part D Medicare Advantage plan (MA-PD), 732 in the retiree drug subsidy plan (RDS). 42% competed the survey: 332 in the MA-PD plan, 290 in the RDS plan.	Retrospective review of electronic medical and pharmacy records from January 1 - September 30, 2006 to identify patients who met coverage gap threshold. Then, cross-sectional mailed survey administered in February and March 2007.	Overall, 22% beneficiaries, with or without a benefit threshold, were unaware or unsure if they had an initial threshold on medication purchases before they would experience a gap in coverage.	Nearly a quarter of Medicare beneficiaries were unaware of the benefit thresholds for their plans.
Cummings JR, Rice T, Hanoch Y (2008) 11	What are the characteristics of people who believe Medicare Part D is too complicated? What are the characteristics of people who endorse one of two policies to simplify the program?	718 individuals 65 years and older were included in this group from a nationally representative telephone survey of 1,876 adults aged 18+	Cross-sectional, nationally representative telephone survey	80% of the full sample believed that Part D is too complicated. 75% among those aged 65+ believe that the number of plans available should be reduced. 83.6% of the total sample think that seniors should be able to purchase a drug plan directly from Medicare; this was reduced to 77% among those aged 65+.	Overall, most adults believe that the Part D program is too complex, that the number of plans should be reduced, and that seniors should have the option of purchasing drugs directly from a Medicare-operated plan. The authors assert that this conveys trust in government-run programs.
Hall JP, Kurth NK, Moore JM (2007) 14	What was the impact of transition from Medicaid drug coverage to Medicare Part D on a sample of dually eligible adults younger than age 65 years with disabilities?	328 (55%) individuals from a random sample of 600 employed Kansas community dual-eligibles participating in the Kansas Medicaid Buy-In Program.	Telephone survey/interviews between February and March 2006.	More than half the participants did not know that, as full- benefit dual eligibles, they could change plans monthly. Individuals who knew they could change plans often did not know how to do so, nor whom to ask for help. Participants had limited knowledge of Part D rules and regulations.	Knowledge of enrollment requirements and plan switching ability was limited among these dual-eligibles.
De Natale (2007) 30	What is beneficiaries’ access to and knowledge of Part D information? What are beneficiaries’ experiences in choosing plans?	72 older adults (56 women and 16 men) with ages ranging from 65-90 from six senior centers in Santa Clara County, CA	Qualitative one- on-one, face-to- face interview study conducted from September – December 2006	Participants report being overwhelmed with Part D information. 21% were not aware of the coverage gap. Beneficiaries were hesitant to switch plans.	Beneficiaries report that understanding the large influx of Part D information is daunting and that the coverage gap is of primary concern. Beneficiaries are reticent to make changes to their plan choices/assignments.
Keenan, TA (2007) 17	What did beneficiaries know about the coverage gap and the LIS option?	400 Part D beneficiaries aged 65+	Cross-sectional telephone survey in October 2007	24% of Part D enrollees did not know if their plan had a coverage gap. Of those who knew their Part D plan had a gap, 78% said they knew about the coverage gap when they enrolled in the plan. Among those whose plans had gap coverage, about 50% had heard of the low income subsidy “extra help” option. However, only 10% thought that they would qualify for the assistance. The few participants who were potentially interested in switching were motivated by the opportunity to possibly save money on their medications.	One in four Part D beneficiaries still are unaware of the coverage gap, a key feature of most Part D plans. Half are unaware of the LIS, and many who are aware believe that they would not qualify for such assistance.
Perry M, Dulio A, Cubanski J (2006) 35	How knowledgeable are beneficiaries about Part D plans? What are their enrollment choices during the 2007 Part D enrollment period?	35 Medicare beneficiaries with Part D plans. 27 are enrolled in Part D plans (8 non-duals in PDPs, 10 dual eligibles in PDPs, and 9 non-duals in MA-PDs), 5 have other creditable coverage, and 3 are not enrolled or have no creditable coverage.	In-person interviews completed October 2006 in 4 cities: Baltimore, Sacramento, Lincoln, and Miami	Interviews revealed that beneficiaries had basic unanswered questions about new Medicare drug benefit and how their own Part D plan worked and did not full grasp the complexity of the program. Few enrollees seemed to be aware of the coverage gap Most enrollees wanted fewer plan choices and more information from reliable, unbiased sources.	Many beneficiaries lacked a basic understanding of their Part D coverage. They called for greater simplification of the program and plans offered to them, but for now they “make do” with what they have rather than shopping around, often due to fear that a new plan would be worse than the plan they currently had.
Winter J, Balza R, Caro F, Heiss F, Jun BH, Matzkin R, McFadden (2006) 19	What were beneficiaries’ information and enrollment decisions for Part D before Part D open enrollment began in 2005?	Full sample is 4732, but most analyses report on 1808 individuals from sample of Medicare-eligible subjects surveyed before open enrollment began for Part D	Web-TV-based Retirement Perspectives Survey (RPS 2005)	39.5% of Medicare population had little or no knowledge about Part D. Many consumers had a lack of information about two main Part D features: 1) insurance against catastrophic drug costs in future, and 2) the premium penalty for late enrollment. The lack of information was most severe among those with a combination of low SES, in bad health and low cognition--54.3% of these consumers had little or no knowledge about Part D plans.	Many elderly consumers failed to understand the value of Part D as insurance against catastrophic prescription drug costs, and may as a consequence failed to enroll, or enrolled in expensive plans that emphasized low premiums or coverage of deductibles rather than catastrophic benefits.
Heiss F, McFadden D, Winter J (2006) 33	What was the Part D enrollment process like for beneficiaries?	2,137 seniors interviewed before open enrollment period (Nov 7–15, 2005) and then after open enrollment period ended (May 16 – June 2, 2006). Results presented for core of 1571 respondents age 65+ in May 2006 who were interviewed in both surveys and had no item nonresponse on key variables.	Web TV-based interview study, the Retirement Perspectives Survey (RPS). Respondents were asked about Part D knowledge and intentions in first interview, and about enrollment-process choices and opinions in second interview.	52% of those who enrolled in Part D by May 2006 agreed that they had difficulty understanding how Medicare Part D works and what savings it would provide. 34% reported that the enrollment process was very complicated, and 43% reported that not all of the medications that the plans promised would be covered were actually covered. While 75% agreed that it was useful to have alternative Part D plans to choose from, 71% also agreed that there were too many alternative plans from which to choose.	More than half of respondents reported difficulty in understanding Part D’s structure, benefits, and formularies. Respondents were overwhelmed by the number of choices offered, but appreciated that they had choices. Respondents with more knowledge of the Part D benefit, prior drug coverage, and poorer health were more likely to enroll.
Keenan, TA (2006) 37	What is beneficiary awareness and understanding of Part D? What is there enrollment status? When did beneficiaries enroll and with whom?	First survey in March 2006 mailed to 38,116 adults; 3602 of 5000 (72%) community elderly took a second survey in September 2006	Cross-sectional mailed surveys	40% of beneficiaries understood their drug plan “not very well” or “not well at all.” Two-thirds said that when compared to the drug insurance plan they had before, their Part D plan was about the same in terms of getting answers to their questions and getting the medications they needed. Only 12% of beneficiaries eligible for LIS thought they would qualify for the subsidy, while 60% of LIS-eligible beneficiaries thought they would not qualify for extra help at all. Only 41% of self-enrolled respondents reported that their plan had a coverage gap.	Although 40% report limited understanding of their Part D plan, respondents gave Part D very high marks, and most would like to continue participation in the plans in which they are currently enrolled. Most believe that their current plan provides them good coverage and satisfactory access to medications. Most respondents who were eligible for LIS did not believe that they would qualify.
Dulio A, Perry M, Cubanski J (2006) 31	What were Part D enrollees’ knowledge and experiences in the first 3 months of the benefit?	21 Medicare beneficiaries; 6 in a stand-alone Part D plan, 6 in a Medicare Advantage plan (4 of whom were automatically enrolled), 5 with creditable coverage, and 4 with no drug coverage. These beneficiaries reside in Baltimore, MD; Lincoln, NE; Miami, FL; or Sacramento, CA	Face-to-face interviews conducted in March 2006	Some beneficiaries did not know the details or were confused by the details of their plans, including the name and cost-sharing structure. Many feel that Part D is too confusing, want a simplified program with fewer choices, and better communication from the government about which plan(s) would be best for them.	Three months into the benefit, beneficiaries expressed confusion about Part D and a desire for simplification of the program.
Kaiser Family Foundation (2005) 16	What do dually-eligible beneficaries know about Part D in late 2005?	4 dually-eligible adult beneficiaries, one each from Miami, FL; Baltimore, MD; Lincoln, NE; and Sacramento, CA	Face-to-face interview, between October 27 and November 16, 2005	3 of the 4 beneficiaries expressed anxiety, suspicion, and hesitancy about the upcoming Part D benefit. All expressed appreciation for Medicaid’s coverage of their drugs and would prefer to maintain the status quo instead of being enrolled in Part D. All 4 expressed notable gaps in their knowledge of the benefit structure and cost sharing under Part D.	In the months leading up to Part D’s implementation, these 4 dually- eligible beneficiaries expressed concern and a lack of knowledge as to how Part D would impact them.

The Part D program

In each study, especially in the months surrounding Part D implementation, Medicare beneficiaries reported confusion about the Part D program. Among 784 beneficiaries surveyed in October-December 2005, 56% described having limited awareness of the upcoming changes to the Medicare program, and 53% did not know that all Medicare beneficiaries were eligible for Part D.³⁶ Of 1500 respondents to 2 telephone interviews in November 2005 and May 2006, 34% said they poorly understood the Part D benefit.³⁵ In a 2005 web-based survey, researchers found greater knowledge gaps among beneficiaries with a combination of low socio-economic status, bad health, and low cognition—54.3% of these beneficiaries had little or no knowledge about Part D plans.²⁰ Differences in beneficiaries’ knowledge by race were also noted: in interviews with 2,694 community-dwelling elderly in the Chicago area in 2006–2007, researchers found that among non-enrollees, Blacks were more likely than Whites to report having been unaware of Part D (13.2% versus 2.4%) and that the program was too difficult to understand (12.9% versus 1.4%).³⁸

Part D’s benefit structure

A majority admitted large gaps in their knowledge of and confusion about Part D’s benefit structure, particularly regarding the coverage gap. A 2007 mailed survey to beneficiaries of Kaiser Permanente Part D plans found that only 22% of high-spending respondents knew whether their plans had a coverage gap.¹¹ In a separate 2007 survey, Hsu and colleagues found a larger percentage of beneficiaries (40%), knew about the coverage gap, but only 50% of those were able to state the monetary threshold to enter the coverage gap within $250.¹⁶ Even when beneficiaries were aware of the coverage gap, they frequently indicated that they did not understand how it worked or how to know whether they were at risk of entering the gap.³⁴ Beneficiaries also reported confusion about the cost-sharing structures and formulary coverage of their plans, such as how their out-of-pocket costs were determined for each prescription purchase.^{13, 33}

The low-income subsidy

At the time of Part D implementation and in later years, beneficiaries demonstrated a lack of awareness about the LIS and misperceptions about their eligibility and how to apply. Nearly one-third of community-dwelling elderly in a 2005 telephone survey thought that only dually-eligible beneficiaries could receive the LIS.³⁶ In an electronic survey in Fall 2006, over 75% of professionals who counsel Medicare beneficiaries reported that beneficiaries were not aware of the LIS benefit, and 83% stated that beneficiaries often did not know how to apply or did not think they were eligible.¹⁹ One-half of community-dwelling elderly in a 2007 telephone survey had heard of the LIS, and only 10% thought that they would qualify for the assistance.¹⁸ Only 12% of LIS-eligible beneficiaries in a large mailed survey in 2007 thought they would qualify for the extra help.³⁹

Medicare beneficiaries’ Part D choices (Table 2)

Table 2.

Medicare beneficiaries’ Part D choices

Reference	Research Question	# of Subjects	Design	Results	Conclusion
Gruber, J (2009) 21	Did Medicare beneficiaries choose the lowest cost stand-alone Part D plan available to them?	55,000 individuals enrolled in a stand-alone PDP, had a Part D claim in 2006, were not employer-insured, dual eligible, or eligible for a low income subsidy or partial subsidy, were in the dataset for 2005 and 2006, and could be matched to a specific Part D plan	Estimates the cost of enrolling in each PDP available to each beneficiary. Two different models: 1) Backwards-looking model models plan choice using 2005 prescriptions; 2) Perfect foresight model models plan choice using 2006 prescriptions.	Only 6–9% of seniors chose the lowest cost plan available to them in 2006. Among those who did not choose the lowest cost plan, seniors would have saved an average of $360–$520 had they done so, based on their prior year’s drug use. 5% of patients would have had savings of as much as $1,360 had they chosen the lowest cost plan using their previous drug use as a guide. Under a “best match” approach, enrollees would have saved an average of 30% if they had chosen the lowest cost plan.	In 2006, the majority of seniors did not make Part D plan choices that maximized their cost savings.
Neuman P, Cubanski J (2009)31	What does Part D enrollment look like in 2009?	Plan enrollment data from the Centers for Medicare and Medicaid Services	Uses publicly available data released by CMS to determine beneficiaries’ prescription drug coverage in 2009	As of February 1, 2009, 17.5 million (39%) of Medicare beneficiaries were enrolled in stand-alone prescription drug plans, 9.2 million (20%) were enrolled in Medicare Advantage drug plans, 7.9 million (17%) had retiree drug coverage, 6.2 million (14%) had other drug coverage, and 4.5 million (10%) had no drug coverage.	The majority of Medicare beneficiaries have drug coverage in 2009. Nearly 40% of beneficiaries are enrolled in stand-alone plans and 20% are enrolled in Medicare Advantage plans.
Patel R et al. (2009) 29	How many beneficiaries are enrolled in the lowest cost plan available to them?	155 Part D beneficiaries, 55% of whom were dual-eligible	Face-to-face intervention to help beneficiary select the Part D plan with the lowest cost	90% of beneficiaries could have realized cost savings by switching to a different Part D plan, with a median $98 and a mean $431 in annual cost savings. Only 45% of 123 participants who were eligible to switch to a lower cost plan that still covered their drugs decided to switch plans. Of 57 beneficiaries who were not receiving LIS, 14 (25%) were identified as eligible to receive LIS.	Only 10% of beneficiaries were enrolled in the lowest cost Part D plan available to them. One quarter qualified for LIS but were not receiving it.
Skarupski KA, Mendes de Leon CF, Barnes LL, Evans DE (2009)36	Does race affect who enrolled in Part D?	2,694 community-dwelling adults aged 65+ in Chicago; 1,784 are black, 910 are white	Cross-sectional interviews between April 2006 and October 2007	Overall, 38% of respondents had enrolled in Part D; 40% of Blacks and 35% of Whites. Blacks were more likely to have enrolled in the program early than were Whites (closer to the Jan 1, 2006 start date). However, in logistic models that controlled for other demographic variables and health characteristics, black race was not predictive of enrollment in Part D as compared to white race.	While a higher percentage of blacks had enrolled in Part D than whites, the analysis suggests that racial differences in enrollment can be explained by other demographic and health characteristics.
Jackson EA, Axelsen KJ (2008)23	Do dual-elgibile and other low-income subsidy beneficiaries make enrollment decisions based on formulary composition?	Users of top 168 drugs dispensed were persons above age 65 years as of October 2007; 20,958,188 persons in 2006; 22,127,705 persons in 2007; 23,485,757 in 2008.	Use publicly available data released by CMS to generate snapshots of formulary coverage and enrollment levels for years 2006 – 2008. Analysis tracked all Part D plans and tracked coverage of 152 of the most common brand name and generic drugs prescribed to seniors.	CMS indicated that 10% of Part D enrollees changed plans between 2006 and 2007 and 12% of Part D enrollees changed plans between 2007 and 2008. Enrollment in benchmark plans decreased significantly between 2007 and 2008: 57.4% of patients were enrolled in benchmark plans in 2006, 52.3% in 2007, and 35.4% in 2008. Non-benchmarked plans gained enrollment primarily because they were less restrictive in coverage. 39.3% of stand-alone Part D plans added or removed 7 or more drugs to or from unrestricted access, with an average of 18.4 drugs removed and 16.1 drugs added.	A small percentage of beneficiaries switched plans from year to year, despite formulary changes by 39.3% of plans between 2006–2008.
Hargrave E, Piya B, Hoadley J, Summer L, Thompson J (2008)32	What have beneficiaries (and providers) experienced in dealing with Part D?	73 community-dwelling beneficiaries enrolled in a Part D plan and used at least 2 prescription drugs in Denver, CO, Richmond, VA, and Portland, ME.	13 focus groups were conducted between July and October 2007.	Most beneficiaries were generally satisfied with Part D and with their ability to obtain needed drugs. Most beneficiaries have not changed, nor are they interested in changing plans. Reasons most often given for not switching plans were 1) beneficiaries’ sense of being overwhelmed by the complexity of research required to find another plan, and 2) the sense that a change would be “rocking the boat,” perhaps placing the beneficiaries in even worse plans than those they had currently.	For the most part, beneficiaries were satisfied with Part D, despite knowledge gaps. Others were unwilling to switch plans because they did not want to undergo the complex processes of selecting and learning to use a new plan and/or were fearful of making a decision that placed them in a “worse” plan.
Keenan, TA (2008)24	Did beneficiaries enroll in Part D? Why? Did they plan to switch plans for 2008?	330 adults aged 65+	Cross-sectional telephone survey in November 2008	40% of respondents reported that they were enrolled in a Part D plan. Of those enrolled, 23% said they enrolled because they turned 65, 21% said they enrolled because they had high drug costs, 17% said they enrolled because they thought they would save money, and 16% enrolled because they wanted to better budget monthly expenses. 59% of Part D beneficiaries agreed with the statement “as long as my plan doesn’t change, I don’t intend to switch”. Respondents with incomes < $30,000 were more likely to look at different drug plan options than those with incomes ≥ $75,000. 77% reported that they made a “good choice” in selecting their Part D plan.	40% of respondents had enrolled in a Part D plan, most often for financial reasons. 59% did not intend to switch their plan unless major changes occurred, and a majority felt they had made a good choice when choosing a plan.
McNerney T (2008)27	Are Part D beneficiaries satisfied with their plans? Do they intend to switch plans for 2008?	571 adults aged 65+	Online cross-sectional survey conducted between November 29 and December 3, 2007	87% were satisfied with their Part D drug plan. 21% had been advised to select consider other Part D plan options for 2008. 19% reported that they were likely to switch plans for 2008. Of those who are likely to switch plans, 97% plan to seek out information about the different options, with 54% using the Medicare website and 48% using plan brochures and plan websites. Potential switchers reported that the choice of prescription drugs is the most important factor when choosing a plan (91%), followed by the cost of prescription co-pays (89%), and the cost of the monthly premium (89%).	In 2007, the majority of Part D enrollees are satisfied with their plans. Only 19% were likely to switch plans.
Heiss F, McFadden D, Winter J (2007)22	Did beneficiaries enroll in Part D? When did they enroll, and what plans did they choose?	Nationally representative sample of community-dwelling US elderly. 1573 respondents who were 65+ in May 2006, eligible for Part D, and interviewed in the Retirement Perspectives Study (RPS) in both 2005 and 2006.	Internet-based survey. Descriptive study of patients’ plan choices in 2006, their satisfaction with plans during 2006, and their subsequent plan-switching from 2006 – 2007.	Of 443 respondents who were “active deciders” (i.e. not auto- or facilitated-enrollment), 349 (78.6%) enrolled in Part D. 288 of the enrollees (90.6%) chose plans with no gap coverage. The 2007 survey found that 17.6% of beneficiaries were dissatisfied with their 2006 plan, while 47.2% were dissatisfied with the coverage gap concept. Of patients who were enrolled in 2006, 62% did not consider switching plans in 2007; 18.4% considered switching but did not; and 10.7% switched plans. Beneficiaries were more likely to switch plans if the premium increased from 2006 – 2007, OR=1.18, p<0.01 or because of “plan dissatisfaction”, OR=5.80, p<0.01. Beneficiaries were less likely to switch plans if their 2006 plan had no deductible, OR=0.608, p<0.05.	Seniors who were “active deciders” do not take full account of the future benefit and cost consequences of their Part D plan selection decisions, or the expected net benefits and risk properties of alternative plans. Rather, beneficiaries responded to the immediate incentives of their current health status and drug expenditures when picking plans.
Levy H, Weir D (2007)25	Did elderly beneficiaries take up Part D benefits available to them? Did low-income beneficiaries enroll in low-income subsidies?	10,175 Medicare-covered individuals ages 65 and older in 2006 enrolled in the Health and Retirement Study (HRS) who were also in the cohort in 2004	HRS interview survey in 2004, 2006.	52.5% of those who were uninsured for drugs in 2004 enrolled in a stand-alone Part D plan in 2006, and another 7.1% were covered for drugs by Medicare HMOs. 69% of Part D plan enrollees reported feeling “very confident” or “somewhat confident” about having made the right decision to enroll, and 86% of them planned to sign up for Part D again in the following year. 11% of respondents said they did not sign up for Part D because they already had good coverage Among those eligible for the Part D subsidy, 7.8% report having applied for it. 25% of respondents overall and 36% of subsidy-eligible respondents reported that they did not apply for the subsidy because they did not know about it.	Despite the complexity of the program, most Medicare beneficiaries seemed to have made enrollment decisions in which they had confidence. Those who enrolled in stand-alone Part D plans had the most choices to make, and 37% reported that the decision was “very” or “somewhat” difficult. Low-income subsidy applications were lower than expected, and many beneficiaries reported being unaware of the program.
Cubanski J, Neuman P (2007)20	Which organizations and Part D plans attracted the most enrollees in 2006? What is the distribution of Part D enrollees by plan type and benefit design?	Plan-level Part D enrollment included 20.4 million enrollees in 2,811 Part D plans (1,446 PDPs and 1,365 MA-PD plans)	An analysis of Medicare Part D enrollment data exploring plan-level Part D enrollment. Also analyzed the distribution of Part D enrollees by plan type (PDP versus MA-PD) and benefit design.	Ten insurance companies account for 72% of Part D enrollment, and two companies, namely UHC PacifiCare (United) and Humana, dominate the marketplace with their AARP MedicareRX and Standard plans. Of 22.5 million Part D enrollees as of July 1, 2006, 16 million (71%) were enrolled in a stand-alone plan while 6.5 million (29%) were enrolled in Medicare Advantage plan. This disparity reflects the more than 7 million low-income beneficiaries who were auto-enrolled into stand-alone plans (>40% of all stand-alone plan enrollees). United’s AARP attracted many beneficiaries, likely because of its “brand”. Humana attracted high enrollment in its Standard stand-alone plan with low premium costs. Only 4% of Part D enrollees had gap coverage for both brand-name and generic drugs. Another 8% were enrolled in plans with generic drug coverage in the gap.	Beneficaries’ plan choices were influenced by name recognition or low premiums or both. Few enrollees chose plans with gap coverage in 2006. Those beneficiaries with minimal drug expenses might have opted to enroll in a low-premium plan likely to be without gap coverage to avoid the late enrollment premium penalty. It is also likely that some beneficiaries were unaware of the coverage gap when they enrolled in Part D or might not have understood the implications of choosing a plan with a gap.
Neuman P, Strollo MK, Guterman S, Rogers WH, Li A, Rodday AM, Safran DG (2007)28	What proportion of seniors enrolled in Part D plans in 2006, and which subgroups were most likely to remain without coverage? What are the experiences of dual eligible Part D enrollees? How do the characteristics and experiences of Part D enrollees in stand-alone PDPs and MA-PD plans differ?	16,072 noninstitutionalized seniors. Participants were respondents to 2003 national survey and a 1% sample of elderly beneficiaries provided by the CMS in June 2006	Augmented longitudinal survey design. Survey was administered between 10/5 and 12/20/2006 using 5 stage survey protocol involving mail and telephone. Seniors received 1 of 3 possible surveys according to their CMS-designated enrollment status: 1) dual eligible, 2) Medicare Advantage, 3) all others.	Fewer than 10% of seniors lacked prescription coverage in Fall 2006. Among seniors who had no drug coverage in 2005, 61% were enrolled in a Part D plan in 2006. 70% of respondents in Part D plans were enrolled in a stand-alone plan; 30% were in a Medicare Advantage plan. Stand-alone plan enrollees were older, poorer and sicker than their Medicare Advantage plan counterparts. The stand-alone plan population had a disproportionate share of dual-eligibles and LIS recipients. During 2006, over 11% of dual-eligible enrollees switched plans, compared to 5.9% among beneficiaries >200% of poverty level. 50% of seniors with incomes 150% or below the poverty level who were potentially eligible for but were not receiving LIS benefits were enrolled in a Part D plan. Of these seniors, only half said that they were aware of the LIS program. Of those that were aware of the LIS program but did not apply, 46% felt that they would not qualify, 35% said that they did not need help with drug costs, and 7% that they did not know how or that it was too much trouble.	Only 10% of seniors still lacked drug coverage by end of 2006--most typically, those who were most difficult to reach (older, lower income, less education) or were in relatively good health. Many beneficiaries who were eligible for the LIS were not receiving it, and lack of awareness of the LIS program appeared to be a factor in the under-utilization of the benefit. Dual eligibles were more likely to switch plans in 2006 than were non-dual eligibles, in part most likely because they have this opportunity monthly and because of the random assignment nature of the auto-enrollment process.
De Natale (2007)30	What were beneficiaries’ experiences in choosing Part D plans?	72 older adults (56 women and 16 men) with ages ranging from 65–90 from six senior centers in Santa Clara County, CA	Qualitative one-on-one, face-to-face interview study conducted from September – December 2006	Of the 72 participants, 37 (51%) were enrolled in Medicare Advantage Part D plans, 16 (22%) in stand-alone Part D plans, 10 had Medicaid or VA drug coverage, and 9 had private drug insurance. When asked about switching plans for 2007, most conveyed hesitation or a lack of interest in making a change from their current plan.	Beneficiaries are reticent to make changes to their plan choices/assignments, preferring to retain their current plan.
Keenan, TA (2007)18	Why did beneficiaries enroll in Part D? Are they satisfied with their choices? Will they switch plans in 2008?	400 Part D beneficiaries aged 65+	Cross-sectional telephone survey in October 2007	69% were extremely or very satisfied with their Medicare Part D plan. 20% said they enrolled because they thought they would save money, 15% said they enrolled because they turned 65, and 13% said they enrolled because of high prescription drug costs. 82% of respondents said they planned to enroll in a Part D plan for 2008, with 80% planning to keep the same plan they had in 2007. 16% said they did not know whether they would switch plans. 78% of respondents felt they had made a good choice in selecting their Part D plan.	Part D beneficiaries were motivated to enroll due to financial reasons and because they turned 65. Most beneficiaries planned to enroll again in 2008, and the majority planned to stick with the same plan in which they were currently enrolled.
McBride TD, Terry TL, Mueller KJ (2006)26	What is Part D enrollment like in rural and urban areas?	39% of all rural Medicare beneficiaries were enrolled in Part D coverage as of March 2006 (3,441,000/8,884,000); a small number (291,000) have drug coverage through MA plan (3.2%) while 21% (1,839,000) were enrollees in PDPs, and 15% (1,328,000) are dual-eligibles.	Cross-sectional, observational study/policy brief, data from CMS available March 2006	Enrollment in Part D in rural areas is high and reflects the high enrollment of Medicaid dual eligibles covered by Medicare who were auto-enrolled in stand-alone plans. Enrollment in stand-alone Part D plans is higher in rural areas (21%) than in urban areas (13%).	More rural beneficiaries are enrolled in the Medicare stand-alone Part D plans, which have equitable characteristics for urban and rural dwellers. Only 3% of rural beneficiaries are enrolled in Medicare Advantage Part D plans. The high enrollment in Part D in rural areas can be partially attributed to the high auto-enrollment of Medicaid dual-eligibles that live in rural areas.
Hibbard J, Greene J, Tusler M (2006)34	What are beneficiaries’ intentions and experiences with regards to enrolling in a Part D plan?	784 community-dwelling elderly individuals age 65+, not dually eligible (1600 originally sampled, response rate 49%)	Telephone survey administered between October 13-December 5, 2005	37% of respondents reported that there were “too many choices” of plans. 16% of respondents planned to enroll in Part D or had already done so. Only 41% of those who had decided on a plan reported having compared the costs and benefits of different plans prior to selecting a plan, and most compared only 4 plans, on average. Others chose plans with which they had a prior relationship or for which they had received information through a representative or advertisement. 44% of those who had not yet decided whether to enroll in Part D stated that they did not yet know enough about their options.	The complexity of the Part D benefit and the number of plan choices may be a barrier to enrollment. More than half of beneficiaries who had enrolled in a Part D plan did not compare the costs and benefits of different plans prior to selection, instead relying on prior experience with insurance plans or obtaining information from advertisements/plan representatives.
Perry M, Dulio A, Cubanski J (2006)35	What were beneficiaries’ enrollment choices during the Part D 2007 enrollment period?	35 Medicare beneficiaries with Part D plans. 27 are enrolled in Part D plans (8 non-duals in PDPs, 10 dual eligibles in PDPs, and 9 non-duals in MA-PDs), 5 have other creditable coverage, and 3 are not enrolled or have no creditable coverage.	In-person interviews completed October 2006 in 4 cities: Baltimore, Sacramento, Lincoln, and Miami	Most Part D beneficiaries did not intend to reassess their plan options for 2007. Reasons included: believing that the plan they have is better than one they don’t know; perception that switching plans is a tedious, overwhelming process; belief that switching plans will actually cause problems; and a lack of assistance to help them choose another plan.	Many expressed lacking a basic understanding of coverage. Most were not interested in switching plans in 2007. For now, they “make do” with the plan they have rather than shopping around, often due to the fear that a new plan will be worse than the plan they currently have.
Heiss F, McFadden D, Winter J (2006)33	What plans did beneficiaries choose during enrollment in 2005–2006?	2,137 seniors interviewed before open enrollment period (Nov 7–15, 2005) and then after open enrollment period ended (May 16 – June 2, 2006). Results presented for core of 1571 respondents age 65+ in May 2006 who were interviewed in both surveys and had no item nonresponse on key variables.	Web TV-based interview study, the Retirement Perspectives Survey (RPS). Respondents were asked about Part D knowledge and intentions in first interview, and about enrollment-process choices and opinions in second interview.	Of the 1571 people in the core sample, 68.1% were enrolled in Part D, 24.5% had other creditable coverage, and 7.4% had no creditable coverage as of June 1, 2006. 61.5% of healthy beneficiaries enrolled in Part D, versus 72.1% of unhealthy beneficiaries. Healthy beneficiaries also had lower rates of other creditable coverage than did the unhealthy: 9.6% versus 19.4%. Seniors who had drug coverage before Part D enrolled at higher rates than did seniors who did not have drug coverage before Part D: 69.3% versus 64.2%. By June 2006, those who reported little knowledge of Part D in November 2005 had enrolled at lower rates than those who reported higher knowledge: 64.2% versus 70.6%.	Respondents with poorer health, prior drug coverage, and better knowledge of the Part D benefit were more likely to enroll in Part D by June 2006.
Keenan, TA (2006)37	Did beneficiaries enroll in Part D? When did they enroll, and what plans did they choose?	First survey in March 2006 mailed to 38,116 adults; 3602 of 5000 (72%) community elderly took a second survey in September 2006	Cross-sectional mailed surveys	30% of respondents enrolled in a Part D plan. The top three reasons cited for enrollment included: 1) enrolling seemed less costly than waiting, 2) high drug costs, and 3) thinking they would save money. 75% of respondents said that it was extremely, very or somewhat easy to select a plan. In choosing a plan, 81% said the specific drugs covered, 81% said the premium amounts, and 80% said the copayment amounts were important to them. Self-enrollees said they were not very likely (45%) or not at all likely (35%) to switch prescription drug plans during the next open enrollment period.	Respondents considered formulary coverage, premium amounts, and copayment amounts when selecting a Part D plan. A majority did not want to switch their plan. This was primarily because they believe that the plan provides them good coverage (although their knowledge is limited) and they are satisfied with the accessibility of medications under their current plan.
Keenan, TA (2006)37	Did beneficiaries enroll in Part D? When did they enroll, and what plans did they choose?	First survey in March 2006 mailed to 38,116 adults; 3602 of 5000 (72%) community elderly took a second survey in September 200	Cross-sectional mailed surveys	30% of respondents enrolled in a Part D plan. The top three reasons cited for enrollment included: 1) enrolling seemed less costly than waiting, 2) high drug costs, and 3) thinking they would save money. 75% of respondents said that it was extremely, very or somewhat easy to select a plan. In choosing a plan, 81% said the specific drugs covered, 81% said the premium amounts, and 80% said the copayment amounts were important to them. Self-enrollees said they were not very likely (45%) or not at all likely (35%) to switch prescription drug plans during the next open enrollment period. Among auto-enrollees, 49% said they were not very likely and 34% said they were not likely at all to switch plans in the next open enrollment period.	Respondents considered formulary coverage, premium amounts, and copayment amounts when selecting a Part D plan. A majority did not want to switch their plan. This was primarily because they believe that the plan provides them good coverage (although their knowledge is limited) and they are satisfied with the accessibility of medications under their current plan.
Dulio A, Perry M, Cubanski J (2006)31	How did beneficiaries decide whether to enroll in Part D? What plans did they choose?	21 Medicare beneficiaries; 6 in a stand-alone Part D plan, 6 in a Medicare Advantage plan (4 of whom were automatically enrolled), 5 with creditable coverage, and 4 with no drug coverage. These beneficiaries reside in Baltimore, MD; Lincoln, NE; Miami, FL; or Sacramento, CA	Face-to-face interviews conducted in March 2006	Some beneficiaries were eager to sign up for Part D, while others felt pressured to do so by the late enrollment penalty. Some Medicare Advantage participants described being auto-enrolled in a Medicare Advantage Part D plan. Beneficiaries who enrolled did not compare large numbers of plans to select the best option, instead relying on name recognition and prior experience with the company. If they did make any comparisons, beneficiaries looked for low premiums and costs and plans that covered all of their drugs.	Rather than methodological comparisons to find the plan that best suited their needs, beneficiaries’ enrollment choices were based on name recognition, prior experience with the company offering a plan, auto-enrollment, or feeling pressured to enroll.

Beneficiaries’ enrollment choices

According to a 2006 national survey of 16,072 community-dwelling seniors, 61% of respondents who did not have drug coverage in 2005 enrolled in Part D plans in 2006.²⁹ These findings are consistent with those of the Retirement Perspectives Study: 68.1% of respondents were enrolled in a Part D plan in 2006, 24.5% had other creditable coverage, and only 7.4% lacked any drug insurance.³⁵ Of 22.5 million Part D enrollees as of July 1, 2006 nationwide, 16 million (71%) were enrolled in a stand-alone plan while 6.5 million (29%) were enrolled in a Medicare Advantage plan. As of February 1, 2009, 17.5 million (66%) Part D enrollees were enrolled in a stand-alone plan and 9.2 million (34%) were enrolled in a Medicare Advantage plan.³¹ Enrollment in stand-alone plans was higher in rural than in urban areas (21% versus 13%), reflecting the more limited presence of Medicare Advantage Part D plans in rural areas.²⁷ Seniors listed the most important reasons they enrolled, which included: 1) enrolling seemed less costly than waiting, 2) high drug costs, 3) anticipated financial savings, and 4) turning 65.^{18, 25, 39} Of all Part D enrollees in one 2006 survey, 69% reported feeling “very confident” or “somewhat confident” about having made the right decision to enroll, and 86% of them planned to sign up for Part D again in 2007.²⁶

Many plans, but poor plan choices

In many studies, Part D-eligible beneficiaries felt that there were “too many choices” when trying to select a plan and felt overwhelmed by the decision.^{19, 33, 35–37} Faced with the prospect of choosing a plan, 81% of 3,602 beneficiaries responding to a 2006 mailed survey reported that the specific drugs covered and the premium amounts a plan offered were important to them, while 80% cited the copayment amounts.³⁹ Selecting a plan that covered all of their drugs was also important.³³ However, in practice, beneficiaries made few plan comparisons to look for these attributes: in a telephone survey, only 41% of Part D plan self-enrollees reported comparing costs and benefits of different plans, and most compared an average of 4 plans.³⁶

Instead of comparing plans, many beneficiaries chose plans with which they had a prior relationship or from which they had received information through a representative or advertisement.^{33, 36} In 2006 plan enrollment data, ten insurance companies accounted for 72% of Part D enrollment, and two plans accounted for 23% of Part D enrollment nationwide, the AARP MedicareRX and Standard plans.²¹ The researchers speculate that high enrollment in the AARP plan was likely due to brand recognition while enrollment in the Standard plan was likely based on its low premium costs.²¹

Regardless of their plan selection strategy, many beneficiaries did not choose the plan that saved them the most money. An economic analysis of 55,000 seniors’ plan choices revealed that only 6 – 9% chose the lowest cost plan available to them in 2006 and seniors would have saved between $360 – $520 had they chosen the lowest cost plan.²² A face-to-face intervention designed to help 155 Part D beneficiaries choose their optimal plan for the following year found that 90% of beneficiaries were not currently enrolled in their optimal plan and could realize cost savings by switching to a different Part D plan for the following year.³⁰

Beneficiaries’ reluctance to switch plans

Despite beneficiaries’ poor plan choices, most expressed little desire to switch plans in order to improve their benefits.³² Reasons for not switching included beliefs that: 1) the plan they have is better than one they don’t know; 2) switching plans is a tedious, overwhelming process; 3) switching plans would actually cause problems; and 4) they cannot switch plans without assistance.^{34, 37} Even when assistance was available, such as in the open enrollment period intervention, only 55 of 123 (45%) of beneficiaries switched plans. ³⁰ This reluctance to switch persisted throughout all study years. Among interviewees enrolled in a Part D plan in 2006, 62% did not consider switching; 18.4% considered switching but did not; and only 10.7% switched plans for 2007.²³ Among 400 respondents to a telephone survey in 2007, 80% planned to keep the same plan in 2008,¹⁸ while another poll found that only 19% considered switching plans for 2008.²⁸

DISCUSSION

In this systematic review, we examined studies concerning Medicare beneficiaries’ knowledge of and choices regarding Part D. Beneficiaries reported substantial gaps in their knowledge of the Part D program, including enrollment requirements and the coverage gap period. Part D knowledge differences across race, health status, and cognition group were documented. A conspicuously large group of beneficiaries eligible for a low-income subsidy (LIS) to defray out-of-pocket Part D costs were unaware of this option, did not think they were eligible, or did not know how to apply.

Regardless of their limited knowledge, beneficiaries enrolled in Part D in large numbers and generally expressed confidence in their decisions. However, confusion and lack of knowledge may have translated into poor Part D plan choices. In 2006, only 6–9% of beneficiaries chose the lowest cost plan available to them.²² Even though beneficiaries subsequently had the opportunity to improve upon their initial plan choices, a majority chose not to switch plans.

While the months just before and just after the Part D implementation on January 1, 2006 were marked by greater gaps in knowledge and greater difficulty with plan selection, there are some data from 2007 and 2008 to suggest that these problems persisted in later years. More data are needed from 2007-present to evaluate whether initial difficulties persisted, have been mitigated over time, or if new difficulties have arisen as the marketplace for plans, premiums, deductibles, coverage limits and offerings has shifted.³¹

Two gaps in understanding were particularly striking and persistent across studies and years: lack of knowledge about the coverage gap and lack of awareness of the low-income subsidy. If beneficiaries are unaware of coverage gap features, then they will make no effort to spend strategically prior to the gap or consider switching to lower cost drug alternatives and will fail to appreciate the advantage of choosing a plan that offers some gap coverage. In the years to come, if the coverage gap period remains part of the Part D benefit structure, improved education of beneficiaries is needed.

The LIS is intended to help those who are most financially vulnerable. At present, an estimated 2.5 million beneficiaries who are eligible for the LIS do not receive it.⁴⁰ The Medicare Rights Center recommends providing LIS educational materials in multiple languages and at several reading levels to reach out to beneficiaries.⁴¹ Groups also advocate minimizing documentation requirements for and/or removing the asset testing process and removing the annual recertification process.⁴² Other initiatives are underway that may make identifying and targeting LIS-eligible beneficiaries easier. Section 113 of the “Medicare Improvements for Patients and Providers Act,” which takes effect in 2010, mandates improved cooperation between the Social Security Administration (SSA), which handles LIS enrollment, and Medicaid state offices, which administer subsidy programs to cover Medicare Part B premiums and co-payments.⁴³ A recently proposed bill would allow the Internal Revenue Service to share financial records of potentially LIS-eligible citizens with the SSA.⁴¹

Despite beneficiaries’ well-reasoned enumeration of plan features that were important to them, they consistently failed to choose the Part D plan with the lowest cost,^{22, 30} had difficulty comparing plans, and often did not even compare plans at all. ^{21, 33, 36} Currently, the Medicare Prescription Drug Plan Finder,⁴⁴ created by CMS, is the only source of comprehensive plan information. The Plan Finder requires that beneficiaries or their caregivers be comfortable with the Internet and able to sift through a vast amount of information and identify the attributes most important to them.⁴⁵ Therefore, assistance from beneficiary counselors and/or enhancements to the Plan Finder would likely be helpful. In addition, given that older adults generally place most trust in their physician and pharmacists, it is important to provide these professionals with easy to use tools about comparative drug price data and plan features.^{46, 47}

A related finding was beneficiaries’ reluctance to switch to a better plan when they were able to do so. This “inertia,” or preference to remain with the status quo, has been described in the economics literature among consumers choosing a health insurance plan⁴⁸ and among employees electing to participate in 401(k) plans and allocating retirement savings.^{49, 50} In the Part D setting, interventions to assist beneficiaries in switching plans may help but cannot remove all barriers: while Patel et al’s intervention offered personnel with the know-how to assist beneficiaries in switching, only 45% of beneficiaries chose to do so. Some inertia may exist because of the relatively high levels of satisfaction Medicare beneficiaries report with the Part D program²⁶ and/or beneficiary reluctance to switch out of plans picked based on brand name recognition or other personal preferences.²¹

In this systematic review, we assembled studies that examined beneficiaries’ knowledge of and choices with regards to Part D from 2005 to the present. We found that beneficiaries had significant gaps in knowledge, especially about the coverage gap period and the LIS. Even though beneficiaries were generally satisfied with their decisions to enroll in Part D plans, most beneficiaries chose a Part D plan that did not best meet their needs, and few expressed a desire to change their selections when given the opportunity to do so. These difficulties seemed to be most pronounced in the months surrounding the Part D implementation period in early 2006, but persist to some extent in subsequent years as well. As the Part D program continues, policymakers and Medicare advocates must monitor changes in beneficiaries’ knowledge and choices regarding Part D and determine whether improvements in educational outreach or other changes are necessary to enhance understanding and good decision making among Medicare beneficiaries.