SEER-MHOS Sample Size Estimator is a web tool able to estimate the number of MHOS respondents that match your cohort selection criteria. The Sample Size Estimator helps investigators generate sample size estimates for SEER-MHOS projects, allowing for tailoring by cancer site, survey timing, and Medicare enrollment.
The SEER-MHOS Sample Size Estimator is a filter. It includes all survey records in the database. Your choices of specific variables and values determine which survey records will be used for sample size estimate at the person-level. Each participant is only counted once in the Sample Size Estimator.
The SEER-MHOS Data Resource incorporates the following information. Please restrict each data source in your sample size estimate to reflect data availability to answer your proposed research question.
For example:
- Proposed studies that include Medication information (Part D), will need to restrict relevant MHOS survey cohorts to 2007-2020.
- Proposed studies looking at cancer survivors may choose to limit their sample based on time from cancer diagnosis to survey date. Survivorship period covers over 40 years from an identified cancer dx.
- Cancer sites have been grouped according to SEER*Explorer definitions
.
Data Source |
Description |
Years |
SEER |
Cancer Clinical Data |
1973 – 2019 |
MHOS |
Survey Cohorts |
1998 – 2021 |
Medicare |
MA Enrollment Files |
1999 - 2020 |
Medicare Part D |
Prescription Drug Claims |
2007 – 2020 |
The SEER-MHOS data resource includes all participants in MHOS cohorts 1-22 that have that have completed at least one survey. Each cohort consists of a baseline survey and a two-year follow-up survey. Participants who responded to a baseline MHOS survey may not have completed a follow-up survey. While not common, participants may have been selected to participate in multiple MHOS Cohorts, resulting in the completion of multiple baseline and follow-up surveys.
Participation in MHOS is not indexed against a cancer diagnosis, therefore participation in a MHOS cohort can occur at any time a person is enrolled in a Medicare Advantage Plan.
Sample selection criteria can include survey timing relative to a cancer diagnosis in the following ways:
Survey Timing |
Definition |
Any Cohort |
Survey Timing=Pre-Cancer Diagnosis |
Participants with any survey(s) prior to a cancer dx |
Survey Timing=Post-Cancer Diagnosis |
Participants with any survey(s) after a cancer dx |
Survey Timing= Pre & Post Cancer Diagnosis |
Participants with at least one survey pre and post cancer dx across any cohort |
Same Cohort |
Survey Timing= Pre & Post Cancer Diagnosis (Same Cohort) |
Participants with at least one survey pre and post cancer dx in the SAME cohort (two years) |
Multiple variables can be added to the filter. Every time a new variable is added, the records that do not match the variable value(s) will be removed from the sample size. The Estimator starts with ALL possible records in the database. For example, until you select one or more specific cancer sites, all cancer sites will be included in the estimate. Each variable you add will remove records, for the data that does not match your selected values.
Category Selection
The Category section contains the operators and the variable values. If multiple values are selected for a variable an OR search is performed between those values. For example, when you select Cancer Site as the variable with multiple variable values, (the image below shows Breast and Cervex Uteri as the values) the Sample Size Estimator searches on patients who were diagnosed with either Breast OR Cervex Uteri as shown in the Category column.

The Comorbidity variable (#2 in both examples) can be either an AND or OR search. The operator option At least one of the above will allows users to search for patients who had a survey with any, but not necessarily all of the selected comorbidity values. The All of the above option requires a patient to have surveyed with all of the selected comorbidity values.
Once the category selections for the variable and have been run, the search statement appears as shown above, with the estimated number of cases under the Sample Size column.
When requesting SEER-MHOS data, The Cancer Site(s) are required on all requests. No more than 10 cancer sites may be included in a single data request.