SEER*Stat can provide delay-adjusted rates and trends using delay-adjustment factors calculated from the CINA (Cancer in North America) Deluxe data file compiled by NAACCR (North American Association of Central Cancer Registries).

Examine delay-adjusted incidence rates and trends for malignant breast cancer for females in the SEER 9 Registries for 1975-2018, and display the rates and trends by race. Use rates, age-adjusted to the 2000 U.S. Standard Population and delay-adjusted using the delay-adjustment factors in the trend calculations. Specifically, calculate the Percent Change (PC) and Annual Percent Change (APC) for the entire time period 1975-2018 and observe the effect of delay-adjustment on both rates and trends.

Key Points

  • With each annual SEER submission, the SEER registries report both cases for a new year of diagnosis as well as updates to records from prior diagnosis years. After a diagnosis year is first reported in a submission, the rates for that diagnosis year tend to rise slightly with each subsequent data submission and level out several submissions after being first reported. The delay-adjustment model was developed to analyze reporting delay in submissions to predict the final level for the rates. Detailed information on the delay model can be found at https://surveillance.cancer.gov/delay
  • Delay-adjustment factors are only calculated for malignant cases in the underlying incidence data. The delay-adjustment databases in SEER*Stat only include malignant cases and this is noted in the database name, i.e., Incidence - SEER Research Data with Delay-Adjustment, 9 Registries, Malignant Only, Nov 2020 Sub (1975-2018). Since this database only has malignant cases, the "Malignant Behavior" checkbox on the "Selection" tab is grayed out and unchecked.
  • The calculation of delay factors creates factors for 'All Cancer Sites combined' and 'All Races combined' that are independent from the factors for individual cancer sites and individual races. In order to simplify the use of delay factors in SEER*Stat, the delay-adjustment databases contain up to 4 different records for a single tumor record. This differs from the standard SEER incidence databases which only include one record per tumor. The inclusion of multiple records per tumor can lead to invalid results, so two variables were added to the database and are required in every analysis on the database in order to address this potential problem. The 'Delay Site' and 'Delay Race' variables are specific to delay-adjustment databases and must be defined in each session on either the 'Selection' tab or the 'Table' tab of the session.
  • In this exercise, we are going to look at female breast cancer cases. The 'Delay Site' variable has breast cancer cases listed as 'Breast (female cases only)' which will be used on the 'Selection' tab. The label 'Breast (female cases only)' does indicate that only female breast cancer cases will be selected, but this selection only applies to the case files that will be included in the analysis. In order to get accurate female breast cancer rates from a female only population, the population needs to be narrowed down to only include females. This will be done by adding a selection of 'Sex'='Female' on the 'Selection' tab in the population and case files window.
  • By default, the output matrix presents delay-adjusted rates, the implicit delay factors of the delay-adjusted rate, observed rates, observed case counts and the population counts. Additional estimates, including delay-adjusted counts and an implicit delay factor for the counts, can be made visible in the Matrix->Options dialog window.

    • SEER*Stat Training Course
    Delay-Adjusted Trends Analysis Exercise 1 (continued)

Step 1: Create a New Rate Session

  • Start SEER*Stat.
  • From the File menu, select New > Rate Session, or use the Rate icon on the toolbar.

Step 2: Data Tab

On the Data Tab:

  • Select the database "Incidence - SEER Research Data with Delay-Adjustment, 9 Registries, Malignant Only, Nov 2020 Sub (1975-2018)".
  • The Age Variable should be "Age recode with <1 year olds".

Step 3: Statistic Tab

Choose the following settings on the Statistic tab. Most of these settings are the default values.

  • Set the Statistic to Trends (Age-Adjusted).
  • Notice the Delay Adjust option is checked and cannot be disabled. This database will produce observed rates in addition to the delay-adjusted rates as part of the output.
  • The Delay Factor selection has the option "Delay Factor" selected and this cannot be changed. At this point, only one set of delay-adjustment factors is available for the data.
  • For this run we will use the default settings for the remaining options:
    • Standard Population : "2000 U.S. Std Population (19 age groups - Census P25-1130)".
    • Age Variable : "Age recode with <1 year olds".
    • Trend Variable : "Year of diagnosis".
    • PC End Points : "One Year".
    • APC Calculation : "Weighted Least Squares".
    • Tiwari Modification for confidence intervals : checked.

Step 4: Selection Tab

On the Selection tab:

  • The Malignant Behavior checkbox in the Select Only section is grayed out and unchecked. The database name (on the data tab) indicates that this database only includes malignant records so this selection is not available for this database.
  • Edit the "Race, Sex, Year Dx (Pop, Case Files)" selection statement to read:
    • {Race, Sex, Year Dx.Sex} = 'Female'
  • Edit the "Other (Case Files)" selection statement to read:
    • {Site and Morphology.Fields.Delay site} = 'Breast (female cases only)'

Step 5: Table Tab

Create a table showing rates and trends by race. The results from a delay-adjustment run will have several more columns than standard rate runs; therefore, this example will use the page dimension to stratify the results.

Since this is a delay-adjusted database, the "Delay Site" and "Delay Race" variables must each be included on either the Selection or Table tab. In this example, the "Delay Site" variables is used on the Selection tab to limit the analysis to a single cancer site. The "Delay Race" variable is being used on the Table tab to stratify the results.

  • Add "Delay Race" as a page variable.

Step 6: Output Tab

  • Give your matrix a title, such as:
    Malignant Female Breast Cancer Incidence Trends
    SEER 9, 1975-2018
    Delay-Adjustment Exercise 1

Step 7: Execute the Session

  • Use the Execute icon, or select Execute from the Session menu, to execute the session.

A dialog will display the progress of the job. When the job completes, a new window will open containing the output matrix.

Step 8: Check Your Results