Classification of occupational activity categories using accelerometry: NHANES 2003-2004

Area of Science:

• Occupational health
• Physical activity research
• Behavioral science

Background:

• Occupational activity (OA) significantly impacts daily physical activity (PA) and sedentary behavior (SB).
• Current methods lack consensus on classifying occupational categories by OA levels.
• Limited population data exists for accelerometer-derived PA and SB across diverse occupations.

Purpose of the Study:

• To provide population estimates of accelerometer-derived PA and SB for 40 occupational categories.
• To systematically classify occupations into high, intermediate, and low OA groups.
• To establish a foundation for exploring OA's relationship with health outcomes.

Main Methods:

• Utilized accelerometer data from 1112 adults (20-60 years) from the 2003-2004 NHANES survey.
• Derived variables included total activity counts/day, counts/minute, and proportions of time in moderate-to-vigorous PA (MVPA), lifestyle, and light PA.
• A summary score, derived from ranking six accelerometer variables, classified occupations into three OA groups: high, intermediate, and low.

Main Results:

• 'Farm and nursery workers' were classified as high OA; 'secretaries, stenographers, and typists' as low OA.
• Higher education/income occupations (e.g., scientists, managers) showed higher MVPA, potentially due to gender composition and leisure PA.
• Men exhibited higher total activity counts and MVPA but similar SB proportions compared to women across all OA groupings.

Conclusions:

• Objective PA measurements enabled precise estimation of PA and SB across occupations.
• Facilitated systematic classification of 40 occupational categories into three distinct OA groupings.
• This classification offers novel avenues for investigating the links between occupational activity and health.