The McMaster Monitoring My Mobility (MacM3) study aims to understand trajectories of mobility decline in later life using multisensor wearable technology. To our knowledge, MacM3 is the first major cohort to combine accelerometry and a Global Positioning System (GPS) to track real-world mobility in community-dwelling older adults.

Between May 2022 and May 2024, MacM3 recruited 1555 community-dwelling older adults (mean age 73.9 years, SD=5.5) from Hamilton and Toronto, Ontario. Of the cohort, 68.4% were female, 62.4% married/partnered, 75.3% had post-secondary education and 62.9% had≥3 comorbidities. Most were Canadian born (69.4%) and white/Caucasian (88.0%), with greater ethnocultural diversity observed at the Toronto site.

At baseline, 56.7% of participants reported no mobility limitations, 15.9% had preclinical limitations and 27.4% had minor mobility limitations. Mean gait speed for the total sample was 1.23 m/s, with a mean Timed Up and Go time of 9.4 s and a 5x sit-to-stand time of 13.0 s. A total of 1301 participants had valid wrist-worn device data, and 1008 participants who agreed to wear the thigh-worn device had valid data (≥7 days with ≥10 hours of wear per day). Step count data (n=1008) revealed a mean of 8437 steps per day (SD=2943), with 5073 steps in the lowest quartile and 12 303 steps in the highest.

Ongoing work aims to develop predictive models of mobility decline by integrating wearable, clinical and environmental data. Pipeline enhancements will enable GPS/inertial measurement unit fusion to explore mobility-environment interactions and support ageing-in-place tools.

We calculate positive predictive values (PPVs) of patients presenting with unexpected weight loss (UWL) being diagnosed with cancer within 6 months, using data from a population of Australian primary care patients to replicate results from a previous UK study.

A diagnostic accuracy study involving calculation of the PPV for any cancer using retrospective data from routinely collected electronic healthcare records. The index date is defined as the first recorded UWL presentation and the reference standard is cancer diagnosis within 6 months of the index date.

This study uses primary care data from the Patron primary care database, linked to hospital admissions data and the Victorian Cancer Registry. We include only patients who presented to their General Practitioners (GPs) at least once between 1 July 2007 and 1 February 2022.

Patients were included if they were at least 18 years of age at the index date, had no previous diagnosis of cancer or previous weight loss intervention, including being prescribed medications for weight loss. 13 306 patients out of a primary care population of 1 791 051 patients were identified that met the eligibility criteria.

When stratified by age, sex and smoking status, we found PPVs lower than those derived in a previous UK primary care study, though still above 3% for male non-smokers over 60, female smokers over 70 and all males over 70. Patients from ages 60–79 with at least one abnormal blood test result had PPVs consistently above 3%, while overall, patients with abnormal blood test results have PPVs of up to 35%.

We confirmed that many PPVs, while consistently below those derived in the UK study, are above clinically significant thresholds and increasing with age and the number of different abnormal blood test results.