The goal of this observational study is to generate a comprehensive, multi-dimensional dataset of health indicators collected from girls and women (aged 10 years and older) with and without ADHD across the lifespan. Participants will be asked to complete a detailed survey about hormonal and developmental life phases, ADHD status and symptoms, childhood experiences, health and well-being, and psychosocial outcomes.

The ADHD-Her: Health, Equity and Resilience Study is an observational cross-sectional online study aiming to compile multiple indicators of health and well-being in girls and women with ADHD. We are aiming to enroll at least 1,460 individuals aged 10 years or older who are assigned female at birth or identify as a girl or woman, recruited from communities across Canada. All aspects of the study will be completed remotely, and will be available in both English and French. We will aim to recruit a minimum of 252 participants evenly distributed across five age strata: adolescence (10-17 years); emerging adulthood (18-25 years); early adulthood (26-39 years); middle adulthood (40-54 years); and older adulthood 55+ years). Study participants aged 10-17 years will be enrolled with a parent as a child-parent dyad, where the parent may also fulfill eligibility criteria and complete adult-specific survey measures as an adult participant in addition to participating as a member of the dyad. The sample size was chosen to allow sufficiently powered analyses between and within groupings, providing a controlled means to estimate associations contingent on age, life stage, and diagnostic status. Child participants will be over-recruited with an additional 180 child/parent dyads to account for the multiple processes that occur through this period of development and within group analyses. Some strata may be overrecruited (i.e., 'suspected') to account for inconsistencies in self-report that result in reclassification to control status to ensure all analyses remain adequately powered. Participants will be enrolled on a rolling basis until sample size requirements for each age stratum are met.

Participants will be considered for inclusion in this study if they: 1) were assigned female at birth or gender identity of girl or woman; 2) are fluent in English or French; 3) are aged 10 years or older; 4) currently reside in Canada. Self-reported intellectual disability will be exclusionary. We will enroll participants who have been diagnosed with ADHD by a healthcare practitioner ('ADHD'), who suspect they may have ADHD but have not been formally diagnosed ('Suspected'), or who have neither confirmed nor suspected ADHD ('Control'). The 'suspected' group is intended to capture potential ADHD cases that may have been missed or misdiagnosed, given evidence of high rates of misdiagnosis among girls and women (Attoe & Climie 2023; Skoglund et al., 2024). Our target enrollment will be 500 'ADHD', 500 'suspected' and 460 'control' participants.

Two protected links to study surveys (one for the parent/guardian to complete and a second for the minor child/adolescent participant to complete) will be emailed to the parent/guardian. Adult participants will acknowledge digital informed consent and assent before accessing the online survey questions. Child respondents will provide assent prior to participation in any study activities.

Recruitment will occur via multiple methods. Advertisements will be posted in communities across Canada (e.g., in medical clinics, ADHD clinics, community centres, etc.) via flyers and posters. In addition, recruitment materials will be posted online through social media posts (e.g., Instagram, Facebook, and LinkedIn), and University websites (e.g., The University of Calgary's 'Participate in Research' website). Potential participants will also be free to share recruitment information through their personal social media/email platforms or forward recruitment information to others, and study collaborators will disseminate recruitment information through their available channels and through community partner organizations. Lastly, eligible participants who have previously enrolled in our research studies and have consented to be contacted for future studies will be invited to participate.

Interested participants will contact the study team via an email address provided on the recruitment materials in order to receive a link to an online screening survey, described below. Alternatively, interested participants can access the screener survey directly through posted links or QR codes on recruitment materials. This screening survey aims to ensure they meet the inclusion criteria and to screen out any automated computer-generated responders. Eligible respondents will then receive an email link to the online study survey, described below, along with a written description of the study's design, purpose, risks and benefits, and ongoing rights to rescind consent. They will also provide consent by electronically signing an informed consent form prior to participation in any study measures.

All surveys will be completed via personal computer, tablet, or mobile phone using secured Qualtrics data collection software hosted through the University of Calgary. All surveys will be accessible in either English or French. In the event no personal device is available, a research assistant will be made available to assist participants in completing their survey responses via telephone or through the secured teleconferencing platform Microsoft Teams, hosted through the University of Calgary Information Technologies department to ensure that the software used is encrypted and complies with local legal requirements to protect the personal health information of all participants. All participants will be given the opportunity to provide feedback and elaborate on their responses via an open-ended comment option that will be available as the final component of their survey. Surveys will take approximately 30 to 60 minutes to complete. Adult and parent/guardian participant surveys will take approximately 30-60 minutes to complete and child/adolescent surveys will take approximately 30-45 minutes to complete. Breaks in answering survey items will be provided as needed, in which responses will be saved, and survey progress can be continued at any time the participant returns to the survey.

A screening survey will allow participants to indicate if they meet any of the inclusion and/or exclusion criteria before participating in the full study. It will provide a brief overview of the purpose of the study, and a reCAPTCHA response item for participants to click to indicate they are not a robot responder. All participants will be asked to indicate their sex, gender, whether they reside outside of Canada, their residential province, whether they speak English or French, and whether they have been diagnosed with intellectual disability. Participants who meet these criteria will then be asked to generate a unique and anonymized participant ID using the first three letters of their mothers' maiden name, and the two-digit number from the day of the month of their birthdate. For example, someone born September 15 whose mother's maiden name was "Smith," would generate a participant ID of "SMI15." These data will ensure participation in the study survey is limited to only those who met inclusion criteria, while also removing identifying information from any subsequently collected data. To link familial data, participants will be asked to indicate if any family members are also participating in the study, and to indicate how they are related. Participants will additionally enter their preferred email address, and should they meet study criteria, will be emailed a copy of the written informed consent document for adult participants, and written informed assent document for minor participants, and a unique link to the full study survey to consent and participate. Completion of this survey should take 1-5 minutes.

Multiple safeguards will be implemented within the screening survey to preserve the integrity of the data and prevent computer-generated responders. First, participants will respond to an open-text question asking, "Briefly, tell us where you heard about this study." Additionally, respondents will be shown hidden text (white font on a white background) instructing them to include the word "banana" in their response. Since only automated bots will detect and follow this instruction, any responses containing "banana" can be filtered out. Participants will also be asked to provide free-text responses following certain parameters (e.g., using specific words) which will further allow us to identify authentic respondents, as well as geolocation data to validate consistency in reported residential province. Embedded data collection measures, such as tracking the number of pastes, keys typed, backspaces used, and speed of completion will be used to further identify authentic and inauthentic responses. Comparisons between responses in the pre-screening survey and the full study survey provide a further validity check to ensure data quality. No further information on familial relations will be asked at the pre-screening stage, but this will allow research assistants to follow up via email, to ensure familial participant responses are linked appropriately in the full study survey.

The full study survey will include questions about sociodemographic details, hormonal and developmental life phases, ADHD status and symptoms, childhood experiences, health and well-being, and psychosocial outcomes. Participants who are parents will also report on aspects of their parent/guardian-child relationship and child behaviour. Where possible, short-form or adapted/shortened measures will be used to reduce participant burden. Additionally, branching logic will be used to display questions, in which only relevant questions will be shown to participants based on their previous answers, and where applicable, an "other" option with a text box for responding will be provided. This online survey should take approximately 30-60 minutes for those aged 18 years or older, and 30-45 minutes for each child/adolescent and their guardians.

The following measures will be administered:

Sociodemographic Characteristics - Demographic Questionnaire (Study-developed): Assesses age, date of birth, sex assigned at birth, gender, sexual orientation, ethnicity, language fluency, geographic location, education, income, residence status, marital status, occupational status, and subjective health. Respondents: adult participants, parent/guardian, child/adolescent participants.

ADHD Diagnostic Status - Diagnostic History Questionnaire (Study-developed): Assesses no ADHD diagnosis, suspected but not diagnosed ADHD, or confirmed clinician-diagnosed ADHD. Collects additional information on ADHD presentation, age of symptom onset, age of diagnosis or suspicion, diagnosing clinician, medication use, and consistency of medication use. Respondents: adult participants, parent/guardian, child/adolescent participants.

ADHD-Related Service Access and Barriers - Health Access Questionnaire (Study-developed): Assesses where participants access ADHD-related information and resources, confidence or satisfaction in physician ADHD knowledge, and perceived obstacles to accessing ADHD information, resources, or diagnostic identification. Respondents: adult participants, parent/guardian, child/youth participants.

Developmental/Hormonal Life Stage - Developmental Life Stage Questionnaire (Study-developed): Assesses current developmental or hormonal stage, including pre-puberty, active puberty, completed puberty, pregnancy, postpartum, perimenopause, or menopause. Respondents: adult participants, parent/guardian, child/youth participants.

Mental Health History and Medication Use - Mental Health Comorbidity and Medication History Questionnaire (Study-developed): Assesses self-reported mental health history, comorbidities, and psychiatric medication use, including depression, anxiety, OCD, bipolar disorder, personality disorders, conduct disorder, oppositional defiant disorder, learning disorders, and other mental health challenges. Respondents: adult participants, parent/guardian, child/adolescent participants.

Menstrual, Reproductive, and Contraceptive Health History - Menstrual Health Questionnaire (Study-developed): Assesses menstrual health history, contraceptive use, hormonal replacement therapy, and women's reproductive health conditions. Respondents: adult participants, child/adolescent participants who have reached menarche.

Adult ADHD Symptoms - Adult ADHD Self-Report Scale, v.1.1 (ASRS-v1.1) (Kessler et al., 2005): Assesses current ADHD symptoms in adults, including inattention and hyperactivity/impulsivity. Used as a validated adult ADHD screener and symptom measure. Respondents: adult participants (age 18+).

Child/Adolescent ADHD Symptoms - Conners-4th Edition Short Self-Report Form ADHD Index (Conners, 2023): Assesses youth self-reported ADHD symptoms. Respondents: child/adolescent participants (age 10-17).

Child/Adolescent ADHD Symptoms (Observer) - Conners-4th Edition Short Parent Report ADHD Index (Conners, 2023): Assesses parent-reported ADHD symptoms in child/adolescent participants. Respondents: parent/guardian.

Emotion Regulation - Difficulties in Emotion Regulation Scale (DERS) (Gratz & Roemer, 2004): Assesses difficulties with emotion regulation, including emotional awareness, clarity, impulse control, goal-directed behaviour, nonacceptance of emotional responses, and access to emotion regulation strategies. Respondents: adult participants (age 18+).

Positive Childhood Experiences - Positive Childhood Experiences Scale (PCEs) (Bethell et al., 2019): Assesses retrospective positive childhood experiences and early relational or contextual strengths. Respondents: adult participants (age 18+).

Adverse Childhood Experiences - BRFSS ACE Module (Centers for Disease Control and Prevention, n.d.): Assesses retrospective exposure to adverse childhood experiences. Respondents: adult participants (age 18+).

Self-Esteem - Rosenberg Self-Esteem Scale (RSES (Rosenberg, 1965): Assesses global self-esteem. Respondents: adult participants; select child/youth participants. Ages 18+; 12-17.

Self-Compassion - Self-Compassion Scale - Short Form (SCS-SF (Raes et al., 2011): Measures self-reported self-kindness, mindfulness, common humanity, and reduced self-judgment. Respondents: adult participants (age 18+).

Loneliness - Revised UCLA Loneliness Scale (Russell, 1996): Assesses perceived loneliness and social isolation. Respondents: adult participants (age 18+).

Mattering/Anti-Mattering - General Mattering Scale (GMS) (Flett, Nepon, & Hewitt, 2022): Assesses perceived importance, significance, and feeling valued by others. Respondents: adult participants, child/adolescent participants. Ages 10+.

Resilience - Brief Resilience Scale (Smith et al., 2008): Measures perceived ability to recover or "bounce back" from stress. Respondents: adult participants (age 18+).

Shame/Guilt - Harder Personal Feelings Questionnaire-2 Brief (Harder & Zalma, 1990): Assesses proneness to shame and guilt. Respondents: adult participants (age 18+).

Masking - Adult ADHD Masking Measure (Behavioral Health Consulting Solutions, 2024): Assesses compensatory strategies and masking or camouflaging of ADHD-related difficulties. Respondents: adult participants (age 18+).

Romantic Relationship Quality - Relationship Assessment Scale (RAS) (Hendrick, 1988): Measures satisfaction and perceived quality in romantic relationships. Respondents: adult participants (age 18+).

Perceived Social Support - Interpersonal Support Evaluation List (ISEL) (Cohen, 1985): Assesses perceived availability of social support. Respondents: adult participants (age 18+).

Health Status - Subjective Rating of Health (Statistics Canada, single-item): Captures global self-rated health. Respondents: adult participants, parent/guardian, child/adolescent participants. All age groups.

Quality of Life/Life Satisfaction - Satisfaction with Life Scale (Diener, Emmons, Larsen, & Griffin, 1985): Assesses global cognitive judgments of life satisfaction. Respondents: adult participants (age 18+).

Life Stress - Holmes-Rahe Life Stress Inventory (Holmes & Rahe, 1967): Assesses cumulative exposure to major life events and associated stress burden. Respondents: adult participants. Respondents: adult participants (age 18+).

Attachment - Attachment Style Questionnaire (ASQ) (Feeney, Noller, & Hanrahan, 1994): Assesses attachment style and interpersonal security or insecurity. Respondents: adult participants; select child/adolescent participants.

Physical Activity - International Physical Activity Questionnaire (I-PAQ) (Craig et al., 2003): Assesses physical activity and sedentary behaviour. Respondents: adult participants; select child/adolescent participants. Ages 18+; 15-17.

Sleep Quality - Brief Pittsburgh Sleep Quality Index (Sancho-Domingo et al., 2020): Brief assessment of sleep quality and sleep disturbance.

Cognitive Functioning - Cognitive Failures Questionnaire (CFQ) (Broadbent, Cooper, FitzGerald, & Parkes, 1982): Assesses everyday cognitive lapses in attention, memory, perception, and action. Respondents: adult participants; select child/adolescent participants. Ages 18+; 16-17.

Mental Health (Depression, Anxiety, and Stress) - Depression Anxiety Stress Scales - 18-item Version (DASS-18) (Keislaman, 2024; Lovibond & Lovibond, 1995): Assesses symptoms of depression, anxiety, and stress. Respondents: adult participants (age 18+).

Parent Self-Stigma - Parent's Self-Stigma Scale (PSSS) (Eaton, Ohan, Stritzke, & Corrigan, 2019): Assesses parental self-stigma, including self-blame, shame, and negative beliefs related to a child's difficulties. Respondents: adult participants (age 18+).

Parent/Child Relationship - BASC-3 Parenting Relationship Questionnaire (BASC-3-PRQ) (Reynolds, 2015): Assesses parent-child relationship quality, including involvement, communication, discipline, attachment, and relational functioning. Respondents: adult participants, parent/guardians. Ages 18+.

Child/Adolescent Behavioural and Emotional Functioning - Behavior Assessment System for Children - Third Edition, Parent Rating Scales (BASC-3) (Reynolds & Kamphaus, 2015): Assesses behavioural and emotional functioning in children and adolescents. Respondents: parent/guardians, adult participants. Ages 18+.

Inclusion Criteria:

• Assigned female at birth or identify as girl or women
• Fluency in English or French
• Aged 10 years or older
• Currently reside in Canada
• Access to technology to complete study measures

Exclusion Criteria:

• Self-reported intellectual disability

Recruitment will occur via multiple methods. Advertisements will be posted in communities across Canada (e.g., in medical clinics, ADHD clinics, community centres, etc.) via flyers and posters. In addition, recruitment materials will be posted online through social media posts (e.g., Instagram, Facebook, and LinkedIn), and University websites (e.g., The University of Calgary's 'Participate in Research' website). Potential participants will also be free to share recruitment information through their personal social media/email platforms or forward recruitment information to others, and study collaborators will disseminate recruitment information through their available channels and through community partner organizations. Lastly, eligible participants who have previously enrolled in our research studies and have consented to be contacted for future studies will be invited to participate.

De-identified individual participant data (IPD) may be shared with other researchers after data collection is complete and after publication of study results. Data sharing will only take place with permission of the principal investigator and in accordance with participant consent, applicable privacy regulations, and institutional data management policies. Data will be shared in coded form for scientific research purposes only and may require a data sharing agreement. Requests for access to the data can be submitted to the principal investigator.

Individual participant data and supporting materials will become available after data collection is complete. Data will be available upon reasonable request for scientific research purposes, subject to approval by the principal investigator and in accordance with participant consent and applicable privacy regulations. Data will remain available indefinitely after completion of the study.

Researchers may request access to de-identified individual participant data (IPD) and related materials for scientific purposes. Accessible materials include the de-identified dataset, along with the study protocol and analytic code. Access requests should be directed to the principal investigator, who will review and approve them in line with participant consent, applicable privacy regulations, and institutional data governance policies. Approved data sharing may be facilitated through a formal data sharing agreement.