February 2006

Introducing ...

A member of the International Scientific Advisory Panel -- Douglas Broadfield, PhD

When David Jackson, DC; Matthew McCoy, DC; and Robert Blanks, PhD founded Research & Clinical Science (RCS), they realized that the credibility and validity of the program would rely in great part on the quality of researchers chosen to analyze the data collected by chiropractors around the world.

They sought out a world‑class group of respected scientists with unimpeachable credentials and proven expertise in health care research. The result of their efforts was the RCS International Scientific Advisory Panel, a multi‑disciplinary group charged with overseeing the collection of, and analyzing, data compiled on hundreds of thousands of volunteers and chiropractic patients across the globe.

Each month during this special series, The Chiropractic Journal profiles one member of this prestigious panel.

Douglas Broadfield, PhD

Dr. Douglas Broadfield, a faculty member in the Departments of Anthropology and Biomedical Science at Florida Atlantic University (FAU) has an important but rather unusual background in biological and medical anthropology.

Biological anthropology deals with the adaptations, variability, and evolution of human beings. Experts in this field may also concentrate in the sub‑field of medical anthropology that deals with the relationship between human culture, social life, patterns of disease, experiences of health and illness, organizations of treatment and the distribution of resources.

Although he began his undergraduate training at Emory University as a premedical student, Broadfield made a dramatic career change during his senior year to pursue a career in anthropology.

The defining moment came during a summer archeological expedition to Lake Turkana in Kenya near the Ethiopian border. The expedition was led by senior primatologists at Harvard University with the purpose of finding human and non‑human fossils remains. Indeed, it was the challenge of distinguishing species, sex, approximate age and dietary patterns from even the smallest fossil bone fragments that launched his interest in biological anthropology.

His research interests brought him to the City University of New York (CUNY) where he completed his Masters (1997) and PhD (2001) in Physical Anthropology. His dissertation research grew out of weekly luncheons with his advisor, Dr. Ralph Holloway of Columbia University, one of the worlds foremost authorities on human brain evolution. Professor Holloway and others are part of the New York Consortium in Evolutionary Primatology between New York University, Columbia, and CUNY.

Broadfield's PhD thesis examined the sex differences in cortico‑cortical fibers crossing within the corpus collosum of chimpanzees and macaques. His research demonstrated that although the chimpanzee corpus callosum is remarkably comparable in size in both sexes, females have a higher proportion of large diameter (> 6 mm diameter) axons.

Because larger diameter axons are more rapidly conducting, the implication was that females have a commissural system that permits more rapid processing of information between the language centers of the right and left cerebral hemispheres for which there is confirming neurobehavioral evidence.

Broadfield was appointed as a faculty teaching assistant in the Department of Cell Biology and Anatomy at the Mount Sinai School of Medicine where he taught gross anatomy to freshman medical students from 1997‑2001. He was then recruited to Florida Atlantic University in Boca Raton, FL where he is currently Assistant Professor in the departments of Anthropology and Biomedical Science where he maintains an active teaching and research program.

The exciting part about biological and medical anthropology is that it enables Broadfield to appreciate the differences in health beliefs, values and behaviors across cultures. To illustrate, he points to the cultural differences in pain perception. For individuals born and raised in the US or Europe, pain is an acceptable feeling and it is a part of the dialog between practitioner and patient.

However, individuals from Central and South America will not know to talk about pain and if they do it must be intolerable. Most practitioners appreciate the subjective nature of pain, but they may not have had special training in evaluating pain tolerance cross culturally. Fortunately, the cross‑cultural differences in health beliefs, values and behaviors (e.g., attitudes towards stress, sexual taboos, mental disease, spirituality and health, etc.), are slowly making their way into the curriculum of medicine and other health disciplines.

When asked about his most important contributions to the field, Dr. Broadfield comments about three areas. First, in the three short years at FAU he has directed the activities of 16 former and current Masters Students in Anthropology with all but three having entered the program since he arrived. His students' research covers a variety of topics ranging from primatology to locomotor morphology to skeletal biology to cognition. Four of six students that have graduate from the program have gone on to PhD programs (Iowa, George Washington, Ohio State, and FAU‑ Comparative Studies Program) and 10 are currently still completing their Masters training.

Second, he has contributed substantially to gross anatomy training of graduate and medical students by way of his unique expertise in musculoskeletal anatomy across human‑ and non‑human primate species.

Third, he has published 46 peer‑reviewed papers and abstracts, six book and book chapters, has been honored to give numerous scientific, community presentations and television interviews. His research has been funded by the National Science Foundation. He is most proud of his new book "The Human Fossil Record, Brain Endocasts (John Wiley and Sons, Inc, 2004), that presents the most complete record in the field covering human brain evolution across four million years of human evolution.

RCS will be collecting imaging material on the spine from participating offices throughout the country and internationally. Broadfield hopes to analyze these x‑rays to assess the benefits of chiropractic care, examine the large data sample to control for sex , age and race/ethnic differences, and possible regional variations of patient responses to treatment, and normal variants.

He anticipates that it will take X‑rays from thousands of individuals to control from the many variables being collected by the RCS Network re. Lifestyle, work activity (office worker vs. field worker vs. heavy iron or assembly line worker), sociodemongraphics, prior medical conditions, current medications, duration of care, etc.

In particular, given that skeletal abnormalities can be related to occupational exposure and lifestyle (tailors knee from reactive osteogenesis, arthritis, wearing of meniscus, or kyphotic spines from sedentary lifestyle and calcium poor diets), a large data repository of the type provided by RCS will be required to control for all confounding variables. There are currently no large repositories containing spinal images from well‑characterized patients that could serve as a study base for biological anthropologists.

Whereas there are well‑documented trends linking health behaviors and disease (osteoporosis, rheumatoid conditions, etc.), the full impact of modern society and its sedentary lifestyle on the spine and articular skeleton has yet to be determined.

(For more information about the research being conducted by RCS, or how doctors of chiropractic can become IRB‑approved and RCS Authorized Clinical Researchers, call RCS at 800‑909‑1354 or 480‑303‑1694.)