BACKGROUND: Realizing population-level discomfort evaluation and
control of common static posture holding tasks requires an understanding of
the inter-individual variation in discomfort perception. However, little
research is available.
OBJECTIVE: This study aimed to determine the types of mathematical
probability distribution suitable for modeling population discomfort
distributions of various static posture holding tasks and characterize how
the magnitude of inter-individual variation in perceived discomfort varies
across static posture holding tasks.
SUBJECTS: Ten male and ten female subjects participated.
METHODS: The participants conducted static posture holding for a
set of 180 short-duration (20-second-long) static posture holding tasks and
subjectively rated the overall perceived discomfort for each task using the
Borg CR-10 discomfort scale. Statistical analyses were conducted according
to the study objectives.
RESULTS: The static posture holding tasks exhibited multifarious
discomfort distribution patterns. Probability distribution identification
analyses indicated that no single distribution type could represent
population discomfort distributions universally across different static
posture holding tasks. Sample standard deviation of discomfort ratings data
quantifying the magnitude of inter-individual variation in discomfort
perception varied considerably across static posture holding tasks. It
seemed to have a positive relationship with sample mean within the range of
the experimental conditions.
CONCLUSIONS: Population-level evaluation of discomforts associated
with static posture holding tasks must be based on careful examinations of
empirical discomfort distributions.