Effectiveness of Mobile Messenger-initiated Reminder on Biannual Mammography Adherence in Breast Cancer Screening

Study Overview
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Brief Summary
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Female breast cancer is the most common cancer and fifth leading cause of cancer death worldwide. In the past decade, breast cancer consistently to be the most common cancer for women in Hong Kong, so much that it accounts for 27% of all female cancers, with 4,600 new cases of breast cancer registration every year and the lifetime breast cancer risk for females is 1 in every 14. At the same time, breast cancer ranks the third in cancer death in Hong Kong, with a five-year relative survival rate of 84%. Regular mammography screening has been shown to reduce the mortality of breast cancer. International guidelines recommend annual or biannual mammography screening for women aged 50 or above. The adherence to regular mammography screening remains a challenge. Studies had shown that the adherence decreased over time. Mailed and telephone reminder were being proven to be effective tools to increase the adherence to regular breast screening using mammography. However, both mailing and telephone strategies are associated with labor intensity and high cost. Over the past two decades, the advent of internet and smartphone provided a fertile platform for the development of mobile-health technologies. WhatsApp Messenger is one of the most frequently used free-of-charge mobile messenger that permits users to send secure messages across different device platforms. A recent randomized controlled trial from our team has suggested its clinical utility in improving adherence to regular colorectal cancer screening using fecal immunochemical test. This encouraging data prompted us to investigate the potential role of WhatsApp Messenger in breast cancer screening. We hypothesized that text reminder sent via WhatsApp Messenger improves the longitudinal adherence to biannual mammography in a community-based, opportunistic breast screening program.

Official Title
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Effectiveness of Mobile Messenger-initiated Reminder on Biannual Mammography Adherence in Breast Cancer Screening

Conditions
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Breast Cancer

Intervention / Treatment
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* Other: Whatsapp reminder


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women with negative mammography results which are defined as BI-RADS (Breast Imaging-Reporting and Data System) 1 or 2 in the first round of mammography screening of the existing opportunistic breast cancer screening cohort Due for second round of biannual follow up of mammography Consented to be contacted via WhatsApp Messenger Exclusion Criteria: Those without access to WhatsApp Messenger or disagreed to be contacted via WhatsApp Messenger

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: WhatsApp Reminder group<br>Subjects who are allocated to the intervention group received reminder via WhatsApp Messenger at one month before the scheduled calendar month of biannual mammography follow-up. | Other: Whatsapp reminder<br>* Subjects who are allocated to the intervention group received reminder via WhatsApp Messenger at one month before the scheduled calendar month of biannual mammography follow-up.<br>|
| No Intervention: No Reminder (NR) group<br>Subjects who are allocated to the NR group received standard-of-care service which is no reminder text messages via WhatsApp Messenger prior to their scheduled repeat mammography and no follow up phone reminder until the completion of the outcome measurement period. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Attendance of the second round of mammography follow up and repeat mammography arrangement. | Primary outcome is the adherence to biannual mammography screening, defined as attendance to the second round of mammography follow up and attendance to the repeat mammography arrangement. | Through study completion, an average of 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Risk factors of nonadherence based on all available variables of patients' characteristics | Secondary outcomes are the risk factors of nonadherence which will be determined by binary logistic regression analysis using all available variables of patients' characteristics | Through study completion, an average of 2 years |