Understanding ADHD in girls and women: A quartercentennial systematic review of symptom expression, prevalence and diagnostic approaches

Over the past quarter century (2000-2025), the discourse surrounding Attention-Deficit/Hyperactivity Disorder (ADHD) in women has expanded considerably, alongside increasing public and clinical awareness of adult and female ADHD. Historically, diagnostic frameworks and clinical descriptions of ADHD were largely developed on the basis of male-dominated samples, emphasizing hyperactivity and externalizing behaviors. This focus has contributed to the longstanding perception that ADHD is less prevalent or less impairing in females and has shaped assumptions about sex- and gender-specific symptom presentation. More recent research has challenged these assumptions, suggesting that differences in symptom expression, coping strategies, and gendered social expectations may contribute to the underrecognition and delayed diagnosis of ADHD in women. At the same time, it is frequently claimed that females remain underrepresented in ADHD research and that current diagnostic frameworks may inadequately capture female-typical symptom profiles. Despite the prominence of these claims, it remains unclear how extensively women have been studied over the past quarter century, how their symptoms have been characterized, and to what extent diagnostic constructs have evolved to accommodate gender-related variations. A systematic synthesis of the empirical research base addressing these issues is therefore still lacking. The aim of this review is to systematically map and synthesize empirical research published between 2000 and 2025 that focuses on the characterization and understanding of ADHD in female populations. The review addresses the following overarching question: How has research over the past 25 years advanced our understanding of gender differences in ADHD symptom expression and the adequacy of diagnostic frameworks for identifying ADHD in women? To address this question, the review examines three interrelated domains: (1) ADHD symptom presentation and gender differences in symptom profiles, including both internalizing and externalizing symptoms; (2) the application and adequacy of DSM and ICD diagnostic criteria for females; and (3) the representation of females in ADHD research, including sample composition, frequency of female inclusion, and potential gender-related biases in study design, reporting, or interpretation. Eligible studies include empirical quantitative, qualitative, and mixed-methods research involving females of any age with a clinical or suspected diagnosis of ADHD. Studies that include male comparison groups are eligible provided that gender-specific outcomes are reported, allowing for direct or indirect comparisons between genders. Reviews, commentaries, and non-empirical publications are excluded. Outcomes of interest include documented symptom profiles and gender differences in ADHD, the frequency and context of female inclusion in research studies, evidence of gaps or biases related to gender, and the appropriateness and limitations of current diagnostic criteria for identifying ADHD in women. By systematically synthesizing findings across these domains, this review seeks to clarify where evidence regarding ADHD in women is robust, where knowledge gaps persist, and where gender bias may continue to influence scientific understanding. This work is highly relevant for patients, who may experience delayed or missed diagnoses; for clinicians, who rely on diagnostic frameworks informed by empirical evidence; and for policymakers, who must ensure equitable recognition and treatment of ADHD across genders. Given the ongoing uncertainty and the clinical and societal consequences of misdiagnosis, a transparent and systematic overview of the research landscape is both timely and necessary.