Sex distribution of study samples reported in American Society of Biomechanics annual meeting abstracts.
BACKGROUND
Study samples should be appropriately selected to maximize generalizability of results. Excluding one sex from studies of conditions that affect both sexes is problematic and has received attention as a public policy issue in the United States, resulting in legislation and recommendations made by the National Institutes of Health to address this deficiency of study designs. It is unknown to what extent biomechanical studies have inappropriately excluded one sex. The objective of this study was to provide objective data on this question.


METHODS
A retrospective review of random samples of abstracts presented at American Society of Biomechanics annual meetings from 1983 to 2013 was conducted to assess reporting of sex of study samples and whether the study samples were approximately balanced with respect to sex.


RESULTS
We did not find a statistically significant increasing trend in the percentage of abstracts reporting sex over time. However, increasing trends were noted in the percentage of abstracts including both sexes (p < 0.05) and percentage of abstracts having an "approximately balanced" study sample containing 50 ± 20% females (p > 0.05). In 2013 the percentage of abstracts reporting studies having approximately balanced study samples was only 28%, far from the ideal level of 100%.


CONCLUSIONS
While there has been modest change since 1983, there remains significant room for improvement in the reporting and composition of experimental studies reported at American Society of Biomechanics annual meetings.
Department of Industrial & Operations Engineering, University of Michigan, Ann Arbor, Michigan, United States of America.
Sarah
S
Bach
Division of Orthopedic Research, Mayo Clinic, Rochester, Minnesota, United States of America.
Melissa M
MM
Morrow
Rehabilitation Medicine Research Center, Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, Minnesota, United States of America.
Kristin D
KD
Zhao
Department of Industrial & Operations Engineering, University of Michigan, Ann Arbor, Michigan, United States of America; Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, Michigan, United States of America.
Richard E
RE
Hughes
D001696:Biomechanical Phenomena; D003226:Congresses as Topic; D005260:Female; D006801:Humans; D008297:Male; D018579:Patient Selection; D011642:Publications; D012106:Research / Q000706:statistics & numerical data*; D012107:Research Design; D012189:Retrospective Studies; D012494:Sampling Studies; D017678:Sex Distribution; D012958:Societies, Scientific; D014481:United States