[Page 386]Although gender and sex are often used interchangeably, the former refers to social constructions of boys and girls, whereas the latter refers to biological sex characteristics. With regard to autism spectrum disorder (ASD), it is generally thought to occur more often in boys (1 in 42) than in girls (1 in 189), according to the Centers for Disease Control and Prevention, and symptom presentation may differ. Research has identified multiple possible explanations for these differences; however, others have questioned the validity of this seeming gender gap. As Melissa Kirkovski, Peter Enticott, and Paul Fitzgerald noted in their review of ASD in girls, the prevalence rates of ASD may be more equal toward the lower functioning end of the spectrum. Yet other research has found ...