The students were divided into four discussion groups of 8 to 12 students each. A female instructor led two of the groups, while a male instructor led the other two. However, the female instructor told one of her online discussion groups that she was male, while the male instructor told one of his online groups that he was female.
Remarkably, in the field of neuroscience the male-to-female ratio of single-sex studies was 5. The authors examined how the investigator preference for studying male animals originated, and they discuss the adverse consequences of this male sex bias in preclinical research for human health.
This article is an excellent resource for gaining an understanding of the historic existence of a sex bias in preclinical animal and human research across ten major biological disciplines including Animal Behavior, Behavioral Physiology, Endocrinology, General Biology, Immunology, Neuroscience, Pharmacology, Physiology, Reproduction, and Zoology.
One of the reasons preclinical research has historically been predominantly conducted on male animals is the mistaken assumption that female mammals are intrinsically more variable than males because of the estrous cycle.
This assumption of greater female trait variability was called into question by Mogil and Chanda, who conducted a meta-analysis of nociceptive responses in forty strains of inbred mice and concluded that there were no sex differences in the response variability [ 7 ].
The authors found that for any endpoint studied, variability was not greater in females than males and in fact for several traits, the variability was greater in males.
The authors identify three classes of sex differences. Included in type I differences are endpoints that are present in one sex but not the other.
For example, only females get pregnant or, for behaviors, courtship rituals, and copulatory behavior differs between males and females. This paper is also a resource for how to study the cause of sex differences and includes decision tree strategies and the methodology for addressing these strategies.
For example, the first recommended experiment is to determine if a sex difference is due to gonadal hormones since most reported sex differences are due to adult gonadal hormone levels. To address this question, the outcome parameter is compared between adult males and females in the intact and gonadectomized state.
Then, depending upon the findings, gonadal hormone replacement studies may be indicated. While this article focuses on the brain, the concepts are relevant to many disciplines. The authors organized this paper as a series of decision tree questions and then provided highly detailed methodologies on how to study the role of male and female gonadal hormones using endocrine ablation and hormone replacement therapy in animals and how to differentiate developmental from adult origin gonadal hormone effects.
In addition, the authors discuss animal models that can be used to investigate the role of the sex chromosomes independently of the gonadal hormones and vice versa. This paper also discusses how to gain insight into the cause of sex differences in humans by taking advantage of naturally occurring changes in the endocrine state across the male and female life span.
Missing from this review, however, is the value of using naturally occurring endocrine disorders e. Another excellent resource for investigators interested in how to design and conduct investigations into the cause of sex differences using cells and tissues from animals or whole animal physiology was written by Miller et.
This article highlights the need to consider reproductive status e. In addition, Miller et al. This paper is also an excellent reference for understanding the impact of how the accumulation of small sex differences can have major effects on outcomes.
Methodological approaches to being able to recognize small sex differences by reducing experimental variation, sufficiently powering studies, and by conducting meta-analyses are presented.
In addition, this article provides a valuable resource for considering overlooked variables in designing sex difference research including sex differences in the pharmacokinetics and pharmacodynamics of drug action when conducting a pharmacological intervention.
This is an excellent resource for Animal Care and Use Committees during their review of animal protocols as Holdcroft recommends guidelines for encouraging disclosure of information that affects sex or gender differences such as strain variations and age of animals.
Moreover, she provides the rationale for why preclinical research design should consider the impact of sex on disease incidence and outcomes.
Investigators are cautioned that the possibility exists for misleading results for improperly conducted SGA, which could mistakenly influence medical management.There is no lack of qualified women to fill leadership roles.
What’s in the way? Gender bias. Why do we assume that people in powerful positions are men – and how can we correct that? Four experiments show that gender differences in the propensity to initiate negotiations may be explained by differential treatment of men and women when they attempt to negotiate.
Psychology experiments about preferences for faces and voices. Objective.
The relationship between sex/gender differences and autism has attracted a variety of research ranging from clinical and neurobiological to etiological, stimulated by the male bias .
Where’s the evidence? A little science about bias and gender equality | Curt Rice [ ] Why are women so uncooperative?
Here I dismantle a claim that women senior. with the study of gender in education, mainly, the studies that tackle the issues of gender in the classroom in general, i.e.
those studies that investigate gender in classroom interaction in different subjects; in addition to other studies that explore the role of gender in the language classroom, and how the focus of the research on gender in.