• The total knowledge score will be collected by the Breast Cancer and Breast Cancer Screening Mammography knowledge questions.
• This questionnaire was modified from an existing breast cancer screening knowledge from Hersch et al. This questionnaire covers mammography, screening benefits and downsides, and guidelines.
• Six of the knowledge questions were scored as correct (1) or incorrect/unsure (0). The percentage of correct scores was calculated per participant pre-intervention and post-intervention (range, 0-100). A higher score indicates higher knowledge.

-The 3-item Values Clarity Subscale (questions 4-6) uses a 5-point response format, ranging from 0 (yes) to 4 (no) to assess feelings of clarity about personal values for benefits and risks/side effects. Items are summed and scores are calculated on a range of 0 (feels extremely clear about personal values for benefits/risks) to 100 (feels extremely unclear about personal values). A higher score indicates less clarity on personal values.

-The 5-Point Decision Self-Efficacy Scale will be modified for breast cancer screening and will measure self-confidence or belief in one's decision-making abilities, including shared decision-making. Questions ask participants how confident they are in a variety of health related skills. This 11-item scale has five response options from "not at all confident" (0) to "extremely confident" (4). Items are summed and scores are calculated on a range of 0-100. A higher score indicates higher decisional self-efficacy.

-The Preparation for Decision Making Scale (PrepDM) assesses a patient's perception of how useful a decision aid or educational materials are in making a screening or treatment decision. The 10-item scale uses a 5-point Likert response format, ranging from 0 (not at all) to 4 (a great deal). Items are summed and scores are calculated on a range of 0-100. Higher scores indicate higher perceived levels of preparation for decision making.

-Adapted acceptability measures from the Ottawa Acceptability Measures including questions eliciting ratings of the information presented in the tool. Each question will ask the participant to rate the information in the tool they viewed as poor, fair, good, or excellent to show what they thought about the way the information was presented.

Stories about other women question was only asked of the Breast Cancer Screening Decision Support Tool arm.

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the length of tool. The questionnaire asks the participant to rate the length of the tool they viewed as too long, too short, just right, or prefer not to answer.

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the amount of information in the tool. The questionnaire asks the participant to rate the amount of information as too much information, too little information, just right, or prefer not to answer.

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the balance of the tool's balance. The questionnaire asks the participant to rate the tool as slanted towards screening, slanted towards NOT screening, balanced, or prefer not to answer

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the usefulness of the tool for decision-making. The questionnaire asks the participant if they would find this decision tool useful when making decision for when to start screening mammography (yes, no, prefer not to answer).

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the helpfulness for decision making of the breast cancer screening decision support tool's questions. The questionnaire asks the participant if the questions in the tool made decision making easier or more difficult or if they prefer not to answer.

This question was for participants enrolled in the Breast Cancer Screening Decision Support Tool arm only.

-Adapted acceptability measures from the Ottawa Acceptability Measures eliciting acceptability ratings of the amount of information in the tool for decision making. The questionnaire asks the participant if the tool provided enough information to help a woman decide when to start breast cancer screening mammography (yes, no, prefer not to answer).

-This is the participants' intention to undergo breast cancer screening within the upcoming year. The questionnaire asks the participant how likely they are to have a screening mammography this upcoming year. Response options include: leaning toward screening (definitely will be tested or probably will be tested), leaning away from screening (probably won't be tested or definitely won't be tested), unsure, and prefer not to answer.