Predictors	Definition and Categories
Patient demographic characteristics
Age group categories	5 categories: <35 y (reference), 35-44 y, 45-54 y, 55-64 y, and ≥65 y
Sex	Men (reference) and women
Race	Non-African American (reference) and African American
Patient clinical characteristics
Time since diagnosis (years)	Time since initial sarcoidosis diagnosis
Comorbid conditions	Each comorbid condition was categorized into 2 groups as present or absent (reference). Each comorbid condition was evaluated as a separate variable. These included hypertension, hyperlipidemia, diabetes, heart conditions, respiratory conditions, gastrointestinal conditions, mood disorder, and chronic joint disease/rheumatoid arthritis. Number of comorbidities
Extrapulmonary sites involved	Each extrapulmonary site was categorized into 2 groups as either a site involved or not involved (reference). Each extrapulmonary site was evaluated as a separate variable. These included skin, joints, bone, and liver. Number of extrapulmonary sites involved
Symptoms	Each symptom was categorized into 3 groups as absent (reference), present as mild severity, or present as moderate-to-severe severity. Each symptom was evaluated as a separate variable. These included shortness of breath, fatigue, bone and joint pain, wheezing/coughing, abnormal heartbeats, depressed mood, chest pain, skin rash, anemia, night sweats, weight loss, and eye symptoms.
Patient’s overall symptom severity	3 groups: mild (reference), moderate, severe
Patient treatment characteristics
No. of comedications used before RCI initiation	Comedication classes considered included biologics, corticosteroids, immunosuppressants, antimalarials, and cytotoxic agents
RCI use	Previous RCI users (reference) and first-time RCI users
Status of RCI treatment at time of data collection	Continuing RCI therapy (reference) and completed a course of RCI therapy
Compliance with RCI treatment	Treatment compliance was assessed at the time of the patient’s visit based on the physician’s response to the question: “On a scale of 1-5, rate the patient’s compliance to Acthar treatment.” The response was measured on a scale of 1 to 5”; where 1 = no compliance, 2-4 = partial compliance, and 5 = complete compliance. No patients reported noncompliance, therefore, only 2 categories, partial (reference) and complete compliance were considered.
RCI initiation dose	≤40 U/wk (reference), 41 U/wk-80 U/wk, and >80 U/wk
Physician characteristics
Physician specialty assessing patient at time of data collection	4 groups: pulmonologist (reference), rheumatologists, primary care physician, other specialties (dermatologist, cardiologist, ophthalmologist, gastroenterologist, neurologist)

Patient demographic characteristics

Age group categories

5 categories: <35 y (reference), 35-44 y, 45-54 y, 55-64 y, and ≥65 y

Sex

Men (reference) and women

Race

Non-African American (reference) and African American

Patient clinical characteristics

Time since diagnosis (years)

Time since initial sarcoidosis diagnosis

Comorbid conditions

Each comorbid condition was categorized into 2 groups as present or absent (reference). Each comorbid condition was evaluated as a separate variable. These included hypertension, hyperlipidemia, diabetes, heart conditions, respiratory conditions, gastrointestinal conditions, mood disorder, and chronic joint disease/rheumatoid arthritis.
Number of comorbidities

Extrapulmonary sites involved

Each extrapulmonary site was categorized into 2 groups as either a site involved or not involved (reference). Each extrapulmonary site was evaluated as a separate variable. These included skin, joints, bone, and liver.
Number of extrapulmonary sites involved

Symptoms

Each symptom was categorized into 3 groups as absent (reference), present as mild severity, or present as moderate-to-severe severity. Each symptom was evaluated as a separate variable. These included shortness of breath, fatigue, bone and joint pain, wheezing/coughing, abnormal heartbeats, depressed mood, chest pain, skin rash, anemia, night sweats, weight loss, and eye symptoms.

Patient’s overall symptom severity

3 groups: mild (reference), moderate, severe

Patient treatment characteristics

No. of comedications used before RCI initiation

Comedication classes considered included biologics, corticosteroids, immunosuppressants, antimalarials, and cytotoxic agents

RCI use

Previous RCI users (reference) and first-time RCI users

Status of RCI treatment at time of data collection

Continuing RCI therapy (reference) and completed a course of RCI therapy

Compliance with RCI treatment

Treatment compliance was assessed at the time of the patient’s visit based on the physician’s response to the question: “On a scale of 1-5, rate the patient’s compliance to Acthar treatment.” The response was measured on a scale of 1 to 5”; where 1 = no compliance, 2-4 = partial compliance, and 5 = complete compliance. No patients reported noncompliance, therefore, only 2 categories, partial (reference) and complete compliance were considered.

RCI initiation dose

≤40 U/wk (reference), 41 U/wk-80 U/wk, and >80 U/wk

Physician characteristics

Physician specialty assessing patient at time of data collection

4 groups: pulmonologist (reference), rheumatologists, primary care physician, other specialties (dermatologist, cardiologist, ophthalmologist, gastroenterologist, neurologist)