Investigating digit ratio (2D:4D) in a highly male‐dominated occupation: The case of firefighters

Voracek, M., Pum, U. & Dressler, S. G. (2009). Investigating digit ratio (2D:4D) in a highly male‐dominated occupation: The case of firefighters. Scandinavian Journal of Psychology, 51, 146–156. Second‐to‐fourth digit ratio (2D:4D), a widely studied putative marker for masculinization through prenatal androgen exposure, is lower (more masculinized) in athletes than in general population controls, and athletes with lower 2D:4D have higher sporting success. Occupations differ markedly in perceived masculinity and actual maleness (sex ratios), but these givens have not yet been picked up and utilized in 2D:4D research. Accordingly, this study extended existing accounts on 2D:4D in athletes to a novel approach: 2D:4D and possible relationships to a variety of candidate variables (demographic, fertility‐related, psychological, and other) were investigated in firefighters, a highly male‐dominated occupation. Contrary to expectation, 2D:4D in firefighters (N = 134) was not lower than in local male population controls. Lower 2D:4D corresponded to lower service ranks. Replicating previous findings either unequivocally or partly, lower 2D:4D was associated with larger family size, later sibling position, left‐handedness, and higher scores in the disinhibition component of sensation seeking. Not replicating prior evidence, 2D:4D was unrelated to body‐mass index, offspring sex ratio, and sporting performance level. Novel findings included low 2D:4D in those with low relationship satisfaction and in cigarette smokers, especially among heavy smokers. Absolute finger length, a positive correlate of pubertal‐adolescent androgen levels, was also considered. This marker showed negative associations with relationship consensus and satisfaction and positive ones with perceived quality of relationship alternatives and the experience seeking component of sensation seeking. The merits of this additional marker, relative to 2D:4D, for supplementing studies of possible sex‐hormonal effects on personality and directions for future inquiry along these lines are discussed.     

Handedness patterns in deaf persons

The handedness patterns of 226 deaf high-school and college students were compared to those of 210 college students with normal hearing. Both groups evidenced many more right-handed than left-handed members, as determined by responses to a hand preference questionnaire and performance on an activity test battery. There was, however, a significantly higher incidence of left-handedness among the deaf subjects than among the hearing. Moreover, the left-handed deaf students were found to be less likely to have deaf relatives, and to have been introduced to sign language later in their development than the deaf student population as a whole. These findings were interpreted as showing that age of acquisition of language was related to the development of handedness patterns, whereas auditory processing experience probably was not.     

The Distressed personality type: replicability and general health associations

The Distressed personality type, identified in a cardiac population, confers risk for worse cardiac outcomes. Whether such a class of persons is identifiable in general patient populations, as well as its health correlates, remains unknown. We investigated these questions in a sample of 482 older primary care patients. Mixture structural equation modelling revealed that a Distressed Type was identifiable in Five Factor Model (FFM) personality data and associated with higher levels of medically documented multimorbidity, and worse subjective health ratings, physician assessed physical functioning and interviewer rated psychosocial functioning. In models including paths from outcomes to both traits and types, traits and types were independently associated with health outcomes, pointing towards the value of considering both approaches in epidemiologic personology research. Copyright © 2007 John Wiley & Sons, Ltd.