Quantifying the effects of body mass index on safety: reliability of a video coding procedure and utility of a rhythmic walking task.
OBJECTIVE
To evaluate the association between body mass index (BMI) and motor actions related to safety risks (primary aim), and to examine the reliability of a video coding procedure and the utility of a rhythmic walking task in identifying safety risks (secondary aims).


METHODS
Using a cross-sectional design, participants were filmed during a rhythmic walking task at slow, normal, and fast audio metronome paces. A video coding procedure was used to quantify signs of safety risks from the videotaped sessions.


METHODS
Motor development laboratory in a university.


METHODS
Adults (N=32) with normal (n=15) and overweight (n=17) BMI scores participated.


METHODS
Not applicable.


METHODS
Chi-squared analyses were conducted to compare the occurrence of coded motor actions (forward and lateral tripping) between participants with normal and overweight BMI scores. A kappa coefficient was computed as a measure of interrater reliability on the video codes.


RESULTS
Participants who were overweight exhibited more safety risks compared with participants with normal BMI scores at the slow (χ(2)(1,N=32)=3.94, P<.05, d=.75) and fast (χ(2)(1,N=32)=3.85, P<.05, d=.74) metronome paces. Interrater reliability was high (κ=.90, P<.01).


CONCLUSIONS
In support of the primary aim, the findings show a relationship between overweight BMI scores and safety risks. Toward the secondary aims, the results demonstrate that a video coding procedure can be reliably used to assess safety risks and that creating tasks appropriate for assessing safety risks in overweight adults is needed.
Department of Occupational Therapy, Boston University, Boston, MA, USA. simvgill@bu.edu
Simone V
SV
Gill
Archana
A
Narain
D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011597:Psychomotor Performance; D015203:Reproducibility of Results; D014741:Video Recording; D016138:Walking / Q000502:physiology*