Association between IRD genotype and change in visual acuity will be reported as change in visual acuity for given IRD genotype.

Association between IRD genotype and change in visual field will be reported as change in visual field for given IRD genotype.

Number and relationship with family members diagnosed with IRD will be described.

Number and distribution of IRD variants and subtypes will be described.

Demographic characteristics of participants (age) will be reported.

Demographic characteristics of participants (sex) will be reported.

Demographic characteristics of participants (race) will be reported.

Number of participants with comorbidities will be reported.

Number of participants with various signs and symptoms (for example: amblyopia, blindness, corneal disease/dystrophy) will be reported.

Number of participants with other ocular events will be reported. Other ocular events of interest including cystoid macular edema, macular hole, epiretinal membrane formation, intraocular inflammation, cataracts, glaucoma, chorioretinal atrophy will be described.

Participant diagnostic pathway prior to diagnosis including number and type of healthcare professional visits will be described.

Participant management after diagnosis including number and type of hospital/clinic visit will be described.

Number and type of hospital/clinic visit, use of assistive device, supportive care, adaptation, and service will be described.

CGIS score will be reported for participants with X-linked retinitis pigmentosa (XLRP) and achromatopsia (ACHM) separately. CGIS is a generic, global, 5-point clinician-administered (observer-rated) scale that assesses illness severity. The score ranging from 1 (no symptoms) through 5 (very severe) to assess disease severity. A higher score indicates more severe disease.

CGIC score will be reported for XLRP participants. CGIC is a global, generic, 7-point clinician-administered (observer-rated) scale that assesses change in illness severity. The score ranging from 1 (very much improved) through 7 (very much worse). A higher score indicates worsening of disease.

The PGIS is a 5-point scale to assess disease severity, for participants with XLRP and ACHM separately. The XLRP PGIS measures participant reported disease severity and impact of XLRP on daily activities, items include: daily activities, mobility, mobility under low luminance/at night, and global rating of severity. A higher score indicates more severe disease. The ACHM PGIS measures participant reported disease severity and impact of ACHM on daily activities, items include: photo aversion (indoors and outdoors), impact on daily activities, and global rating of severity. A higher score indicates more severe disease.

PGIC is a 5-point scale to assess the patient-reported change in disease severity. The XLRP PGIC assesses participant reported perceived change in disease severity and impact of XLRP on daily activities, items include: daily activities, mobility, mobility under low luminance/at night, and global rating of change in severity. A higher score indicates worsening of disease.

The mLLQ is a modified version of the original low luminance questionnaire developed for use in eye diseases to assess self-reported task difficulty under low luminance and at night. The mLLQ uses 5-point or 6-point Likert scales, consists of 6 domains: driving, extreme lighting, mobility, emotional distress, general dim lighting, and peripheral vision. There are 3 age versions: the adult (greater than or equal to [>=] 18 years) version includes 30 items, the adolescent (12-17 years) version includes 22 items, and the caregiver (3-11 years) version includes 19 items. Each domain has a score range of 0-100, with higher scores reflecting a higher level of functioning. Scores will be described per age class separately only for participants with XLRP.

The AVIQ was developed to assess the impact of ACHM on functional vision in children and adults. The AVIQ uses 5-point or 6-point Likert scales. There are 3 age versions: the adult/adolescent (>= 12 years) version includes 15 items, the child (8-11 years) version includes 8 items, and the caregiver (5-7 years) version includes 5 items. Scores will be described per age class separately.

The ACHM symptom and impact diary assesses the severity of key symptoms of photosensitivity and impaired visual acuity, contrast sensitivity, and color vision. There are 3 age versions: the adult/adolescent (>=12 years) version includes 9 items, the child (8-11 years) version includes 9 items, and the caregiver (5-7 years) version includes 16 items. Scores will be described per age class separately.

The HADS is a 14-item questionnaire to assess the presence of anxiety and depression in individuals aged 16-65 years, using 4-point Likert scales. Summary scores are reported for the 2 domains. Each domain has a score range of 0-21, with higher scores reflecting increased anxiety or depression.

The WPAI is a 6-item questionnaire that measures the effects of IRD symptoms on work productivity and absenteeism and activity impairment outside of work, using dichotomous (Yes/No) and 0-10 numerical rating scale. The productivity loss would be the total work impairment; the sum of absenteeism and presenteeism. Scores are expressed as impairment percentages, with higher scores reflecting more impairment. This questionnaire will be answered by both study participants and caregiver participants.

The caregiver burden score is a 14-item questionnaire developed to assess the impact of IRDs on caregivers of children (ages 3-17 years) with an IRD diagnosis, using 4-point or 6-point Likert scales. It measures caregiver burden in terms of perception of their physical and emotional health, relationships, social life, work, and finances. This questionnaire applies to caregivers of minors only.