Church Contextual Factors Associated With Latinx Physical Activity and Park Use

Influence of pre-processing criteria on analysis of accelerometry-based physical activity

BACKGROUND

Accelerometers are widely adopted for physical activity (PA) measurement. Accelerometry data require pre-processing before entering formal statistical analyses. Many pre-processing criteria may influence PA outcomes and the processed sample, impacting results in subsequent statistical analyses.

AIM

To study the implications of pre-processing criteria for accelerometer data on outputs of interest in physical activity studies.

METHODS

We used the ActiGraph hip-worn accelerometry data from 538 adult Latino participants. We studied four most important domains of pre-processing criteria (wear-time, minimum wear-time, intensity level, and modified bouts). We examined the true sample size in pre-processed data, the moderate-to-vigorous physical activity (MVPA) outcome, and regression coefficients of age and gender predicting MVPA.

RESULTS

Many pre-processing criteria have minimum impact to the output of interest. However, requirements for minimum wear-time can have high influence on subsequent analyses for MVPA. High requirements for wear-time (e.g., minimum of 5 days with more than 12 hours of wear-time per day) lead to weakened statistical efficiency in estimating the relationship between potential predictors and the MVPA outcome. Intensity levels using vector magnitude triaxial counts yielded drastically different results than those using conventional vertical axis counts.

CONCLUSION

Moderate changes in minimum wear-time can yield notably different output data and subsequently influence analyses assessing the impacts of interventions on MVPA behaviors. Processed data using vector magnitude and conventional vertical axis counts are not directly comparable. Sensitivity analyses using alternative pre-processing scenarios are highly recommended to verify the robustness of analyses for accelerometry data.

Modifying Text Messages from a Faith-Based Physical Activity Intervention with Latino Adults in Response to the COVID-19 Pandemic

BACKGROUND

Text messages are useful for health promotion and can be modified during public health emergencies.

PURPOSE

Describe how we developed and implemented a physical activity (PA) text messaging component within a faith-based intervention, modified the text message content in response to the COVID-19 pandemic and evaluated participants' perceptions of the modified text messages.

RESEARCH DESIGN AND STUDY SAMPLE

PA promotion text messages were delivered to predominately Spanish-speaking, churchgoing Latino adults (n = 284) in Los Angeles, California. In 2020, we modified the messages to disseminate COVID-19-related information and support and share virtual PA resources.

DATA COLLECTION AND ANALYSIS

We analyzed quantitative and qualitative survey data to gauge participants' experiences with the text messages.

RESULTS

COVID-19 related text messages were a feasible, acceptable addition to a PA intervention for a sample of Latinos.

CONCLUSIONS

Throughout the pandemic, the messages enabled continued communication and support for PA and protection from COVID-19 in a population at high-risk of health inequities.