HBI score is used to assess disease severity and treatment effectiveness. The HBI consists of a 5-part questionnaire, assessing general wellbeing, abdominal pain, number of liquid stools per day, abdominal mass and complications. Clinical response for CD is defined as the reduction in HBI by greater than or equal to (>=)3 points from baseline or achieving HBI less than or equal to (<=) 4.

PMS is used to assess disease severity and treatment effectiveness. The PMS comprises 3 categories: rectal bleeding, SF, and physician assessment. These are rated from 0-3 and are totaled to give a total score that ranges from 0-12. Higher score indicates severe disease. Clinical response for UC is defined as the PMS score less than (<) 4 or >= 30 percent (%) reduction from baseline.

HBI score is used to assess disease severity and treatment effectiveness. The HBI consists of a 5-part questionnaire, assessing general wellbeing, abdominal pain, number of liquid stools per day, abdominal mass and complications. Clinical remission for CD is defined as a HBI score <= 4.

PMS is used to assess disease severity and treatment effectiveness. The PMS comprises 3 categories: rectal bleeding, SF, and physician assessment. These are rated from 0-3 and are totaled to give a total score that ranges from 0-12. Higher score indicates severe disease. Clinical remission for UC is defined as the PMS score < 2 and a rectal bleeding subscore of 0.

Corticosteroid free clinical response for CD is defined as a HBI score <= 4 or decrease in HBI >=3 from baseline and no use of corticosteroids for at least 30 days.

Corticosteroid free clinical response for UC is defined as the PMS score < 4 or >= 30 % reductions from baseline and no use of corticosteroids for at least 30 days.

Corticosteroid free clinical remission for CD is defined as no use of corticosteroids for at least 30 days and a HBI score <= 4.

Corticosteroid free clinical remission for UC is defined as no use of corticosteroids for at least 30 day, PMS score < 2 and a rectal bleeding subscore of 0.

Corticosteroid free PRO-2 remission for CD is defined as mean AP score <=1 and a mean SF score <=3, and no worsening of AP or SF compared with baseline with no use of steroids for at least 30 days.

Corticosteroid free PRO-2 remission for UC is defined as SF subscore of 0 or 1, where the SF subscore has not increased from baseline, and a rectal bleeding subscore of 0 with no use of steroids for at least 30 days.

Characteristics of participants (age) receiving guselkumab treatment will be reported.

Characteristics of participants (sex) receiving guselkumab treatment will be reported.

Characteristics of participants (smoking status and history) receiving guselkumab treatment will be reported.

Characteristics of participants (height) receiving guselkumab treatment will be reported.

Characteristics of participants (weight) receiving guselkumab treatment will be reported.

Characteristics of participants (age at diagnosis) receiving guselkumab treatment will be reported.

Characteristics of participants (disease duration) receiving guselkumab treatment will be reported.

Characteristics of participants (disease severity at index) receiving guselkumab treatment will be reported.

Characteristics of participants (comorbid diagnoses) receiving guselkumab treatment will be reported.

Characteristics of participants (history of UC/CD) receiving guselkumab treatment will be reported.

Characteristics of participants (previous IBD medication use) receiving guselkumab treatment will be reported.

Characteristics of participants (Previous IBD-related surgeries) receiving guselkumab treatment will be reported.

An adverse event is any untoward medical occurrence in a participant administered a medicinal product based on appropriate medical judgment. An AE does not necessarily have a causal relationship with the treatment.

An adverse event is any untoward medical occurrence in a participant administered a medicinal product based on appropriate medical judgment. An AE does not necessarily have a causal relationship with the treatment. An adverse event is considered drug-related if there is at least a reasonable possibility that the study drug contributed to the event.

A serious adverse event, is any untoward medical occurrence or any adverse drug reaction that at any dose: results in death, is life threatening (the participant was at risk of death at the time of the event; it does not refer to an event that hypothetically might have caused death if it were more severe), requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, is a suspected transmission of any infectious agent via a medicinal product and is medically important.

A serious adverse event is any untoward medical occurrence or any adverse drug reaction that at any dose: results in death, is life threatening (the participant was at risk of death at the time of the event; it does not refer to an event that hypothetically might have caused death if it were more severe), requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, is a suspected transmission of any infectious agent via a medicinal product and is medically important. An SAE is considered drug-related if there is at least a reasonable possibility that the study drug contributed to the event.

CRP normalization is defined as less than or equal to (<=) 5 microgram per liter (mg/L) since baseline (among participants with elevated CRP at baseline). C-reactive protein is a marker of inflammation that will be measured by physicians following routine clinical practice.

Change in CRP levels since guselkumab initiation will be reported. C-reactive protein is a marker of inflammation that will be measured by physicians following routine clinical practice.

fCAL normalization is defined as percentage of fCAL <= 250 microgram per gram (mcg/g) since baseline (among participants with calprotectin elevation at baseline). fCAL is a marker of inflammation that will be measured by physicians following routine clinical practice where higher values indicate greater intestinal inflammation.

Change in fCAL levels since guselkumab initiation will be reported. fCAL is a marker of inflammation that will be measured by physicians following routine clinical practice where higher values indicate greater intestinal inflammation.

Number of participants receiving concomitant IBD medications during guselkumab treatment will be reported.

Change from baseline in HRQoL as measured by bowel urgency will be reported. Bowel urgency from participants will be asked as yes or no.

Change from baseline in HRQoL for CD will be measured by PRO-2 components. The CD PRO-2 consists of 2 items: abdominal pain (AP) and stool frequency (SF). AP is a numeric variable with a score between 0-3 and is self-reported by the participant for the 3 days preceding assessment as 0 (no pain), 1 (mild), 2 (moderate) or 3 (severe pain). SF is also a numeric variable calculated the number of liquid stools a participant has experienced over the past 3 days.

Change from baseline in HRQoL for UC will be measured by PRO-2 components. The UC PRO-2 is composed of rectal bleeding and stool frequency. Rectal bleeding is a numeric variable with a score between 0-3 and is self-reported by the participants for the 3 days preceding assessment as 0 (None), 1 (Streaks of blood with stool in less than half of the cases), 2 (Obvious blood with stools in most cases) or 3 (Blood alone passes). SF is also a numeric variable calculated the number of liquid stools a participant has experienced over the past 3 days.

The SIBDQ is a health-related quality of life (HRQoL) tool measuring physical, social, and emotional status in IBD participants. The SIBDQ is a 10-item survey measuring HRQoL over the last 2 weeks (frequency of bowel movement, abdominal cramps, fatigue, lack of energy, worry of surgery, fear of no toilet, ability to relax, irritable, impact on leisure, impact on intimacy). The total score ranges from 10 to 70, where high score indicates better QoL.

The FACIT-F scale is a 13-item instrument designed to assess fatigue/tiredness and its impact on daily activities and functioning in chronic diseases. The instrument includes items such as tiredness, weakness, listlessness, lack of energy, and the impact of these feelings on daily functioning over the last 7 days. Scores are numeric and range from 0 to 52 with higher scores indicating less fatigue.

TSQM-9 is an abbreviated version of the 14-item TSQM, and is a reliable and valid measure to assess treatment satisfaction. It consists of 9 items distributed in the domains: side effects, effectiveness, convenience, and global satisfaction, with scores at each domain ranging from 0 to 100. Here, higher scores indicating greater satisfaction for that domain. A positive change from baseline indicates improvement.

Endoscopic response defined as 50% improvement from baseline in SES-CD total score, or SES-CD total score <4. SES-CD score can range from 0 to 56. Higher scores indicating more severe disease.

Endoscopic remission is defined as SES-CD total score <=4 with at least 2 points reduction from baseline and no subscore >1 in any individual component. SES-CD score can range from 0 to 56. Higher scores indicating more severe disease.

Endoscopic improvement is defined as Mayo score <=1. The Mayo Clinic Score is a composite index with total score ranging from 0 to 12. Higher scores indicate worse disease activity.

Endoscopic normalization is defined as Mayo score =0. The Mayo Clinic Score is a composite index with a total score ranging from 0 to 12. Higher scores indicate worse disease activity.

Histological improvement defined as neutrophil infiltration in <5% of crypts, no crypt destruction, no erosions and ulcerations or granulation tissue according to the Geboes grading system, that is, Geboes score <=3.1.

Histological remission is defined as the absence of neutrophils from the mucosa (both lamina propria and epithelium), no crypt destruction, no erosions, ulcerations or granulation tissue according the Geboes grading system, that is, Geboes score <=2B.0.

IUS response is defined as reduction of BWT of >=25% or normalization (<=3 millimeters [mm]) of the most affected segment at Weeks 24, 48, 72, 96 in participants with increased BWT (>3 mm) at baseline (Week 0).

IUS remission is defined as normalization of BWT (<=3 mm) and vascularity (no signal or short signal in color doppler of the most affected segment) at Weeks 24, 48, 72, 96, in participants with increased BWT (> 3 mm) at baseline (Week 0).

Change from baseline in the number of emergency room visits for treatment of UC/CD will be reported.

Change from baseline in the number of hospitalizations for treatment of UC/CD will be reported.

Change from baseline in the number of surgeries for treatment of UC/CD will be reported.